## LATEST ENTRIES

October 11th, 2015

Interesting:

Hero worship

Another case where we see evidence of a fixed mindset is with hero worship. So Julie Pagano did a great talk at PyCon 2014 about impostor syndrome, and one of her suggestions for a way to combat impostor syndrome was “kill your heroes.” Don’t put other programmers on a pedestal, don’t say “that person is so different from me.” Fixed/growth mindset is a really useful framing for this too. If you have programming heroes, do you consider them to ...

October 11th, 2015

# The protest at 200 meters at the 1968 Summer Olympics in Mexico City

All 3 men are wearing the circular badge for Human Rights, a movement among the athletes:

Norman was a white man from Australia, a country that had strict apartheid laws, almost as strict as South Africa. There was tension and protests in the streets of Australia following heavy restrictions on non-white immigration and discriminatory laws against aboriginal people, some of which consisted of forced adoptions of native children to white families.

October 10th, 2015

# A Java Hashmap is not a Clojure collection

I did not know this till just now. I have a co-worker who wrote a library in Java. From my Clojure code, I call this Java function:

public HashMap<String,HashMap<String,Integer>> init(String debrief,String companyName, ArrayList<String> contacts, ArrayList<String> accounts, ArrayList<String> requiredFields) { try { return transformer.transform(debrief, companyName, tecClassifier, rollioClassifier, caseClassifier, caselessClassifier, customClassifier, pipeline, parser, props, firstNames, lastNames, accounts, contacts, requiredFields); ...

October 10th, 2015

# The TCP checksum is weak, and the Ethernet checksum will accept corrupt TCP that passed the TCP checksum

Interesting:

At Twitter, a team had a unusual failure where corrupt data ended up in memcache. The root cause appears to have been a switch that was corrupting packets. Most packets were being dropped and the throughput was much lower than normal, but some were still making it through. The hypothesis is that occasionally the corrupt packets had valid TCP and Ethernet checksums. One “lucky” packet stored corrupt data in memcache. Even after the switch was replaced, the errors continued until ...

October 10th, 2015

# When is computer programming easy?

Interesting:

While it is often thought that “real” programmers like real programming environments (my husband, for instance, is perfectly happy in MF Assembler, which is pretty grim), most programmers seem to become pretty happy moving up to graphical user interfaces and visual environments where they choose from a list of “correct” choices. I don’t think it is only users that can be more productive when they are better supported.

I believe there is a direct relationship between the ease of use of ...

October 7th, 2015

# How central bankers propose marriage

Interesting:

Greenspan’s marriage proposal to Andrea Mitchell was riddled with his trademark ambiguity. Bernanke, in contrast, proposed after two months of courtship.

Source

October 6th, 2015

# How easy is it to write immutable Javascript?

If you reinvent the language as a new language, then you can have immutable Javascript. On the frontend you have no choice, but on the backend? Why not use a language that offers what you need upfront, rather than forcing you to work for it? Interesting:

The main issue I’ve had using immutablejs with Redux is debugging. Whereas previously I could simply mouse-over a data structure when I hit a breakpoint (or crash), I now have to do a REPL ...

October 4th, 2015

# Erlang – OTP – Cowboy are the cutting edge

At the current time, the only thing out there, in the tech industry, that might cause me to move a way from Clojure, is something build around the Erlang VM . In those situations where performance and massive concurrency are needed, something like Erlang/Cowboy or Elixir/Phoenix need to be looked at.

I load tested (using wrk) nginx serving a two line, static HTML file, against a basic Cowboy service that parsed parameters, did an ETS lookup, and rendered several hundred ...

October 4th, 2015

# Clojurescript as the frontend to Erlang

Radically different, yet becoming more common:

We use vanilla SmartOS, so that there is no dependency on FiFo for your running VM’s. You could just switch FiFo off and all your VM’s would continue to just work. It also comes with a number of great advantages:

In our opinion, ZFS is simply the only file system that should ever be used – period.

Compression, ARC and ZIL work incredibly well, especially for DalmatinerDB which achieves amazing throughput partially thanks to being purpose ...

October 4th, 2015

# Based on this, I just enabled Ghostery on my machine

Interesting:

That’s why the implied-contract theory is invalid: people aren’t agreeing to write a blank check and give up reasonable expectations of privacy by clicking a link. They can’t even know what the cost of visiting a page will be until they’ve already visited it and paid the price.

And it’s all getting so much worse, so quickly.

I’ve never been tempted to run ad-blocking software before — I make most of my living from ads, as do many of my friends and ...

October 4th, 2015

# Hacking environmental protection features

Interesting:

Well, it turns out that all this environmental friendliness is starting to trip over itself, because most devices now start up in standby mode. So you can’t just power them on to power them on, you have to power them on and hit a button on the remote. Some devices, by pure dumb luck I assume, will accept the switch already being pressed in when they start. If that’s the case, you can hack the behaviour you want if you ...

October 3rd, 2015

# Women in Japan now work more than women in the USA

An interesting graph:

To me, the interesting thing is that the trend is up in Japan, and down in the USA.

In the USA, the big surge for women was from 1935 to 1985, with a lull during the 1950s.

In Japan, it looks like a prolonged upward trend started around 2002. The trend is intensifying, which is interesting, but there is a better question we should ask: for most of the last 60 years, women in Japan have had ...

October 3rd, 2015

# Are we in a recession?

When I was young, one thing that surprised me was the debate that occurred around the possibility of a recession in the early 90s. For me, personally, the economy sucked, and I thought we were in a deep recession. Then I started seeing magazine articles wrestle with the question, could we be entering a recession? Years later, NBER declared the recession had started in July of 1990, so the whole time people were debating the possibility of a recession, we ...

September 28th, 2015

# The Liar, The Bitch and the Wardrobe

(The 2nd of 20 reviews of romance novels. I’m reading romance novels so I can learn how to better write about romance in my own works of fiction. My first review was of Evening)

The Liar, The Bitch and the Wardrobe is by Allie Kingsley

This is a very light book. I might compare it to Augusten Burroughs book Sellevsion, which was a bit of light comedy.

Kingsley’s book might have been written as a Young Adult book. I don’t mean that as ...

September 26th, 2015

# 積ん読

Interesting:

There are some words out there that are brilliantly evocative and at the same time impossible to fully translate. Yiddish has the word shlimazl, which basically means a perpetually unlucky person. German has the word Backpfeifengesicht, which roughly means a face that is badly in need of a fist. And then there’s the Japanese word tsundoku, which perfectly describes the state of my apartment. It means buying books and letting them pile up unread.

The word dates back to the very ...

September 26th, 2015

# The Recursive Function Pattern Matching Pattern

Sean Johnson has a great video up. Common in Erlang, useful in Clojure, 3 functions, one to start, one to do the work, one to end, all defined by arity, using Pattern Matching.

Also called the “Start, Work, End” pattern.

This is often done in Clojure with zipmap, but this does not make things as clear as the Erlang version:

This is much more clear:

Source

September 26th, 2015

# Best practice pattern matching in Clojure

If your function starts with a conditional, replace that with pattern matching:

Source

September 16th, 2015

# Never a victim or always a victim

I like this understanding of trauma:

Psychologist Mark Epstein argues that trauma’s root is less the fact that bad things happen and more the fact that we don’t know what to do with what’s bad. Trauma is rooted in lack of communication. Sharing our experiences with another person—facing the traumas we are made of, and the new ones that continually shape us, Epstein says, helps create a balanced mind that can hold the truth. Better this than just telling ourselves that ...

September 16th, 2015

# Racist school administrators go after Islamic child for science project

14 year old boy arrested for bringing a science project to school.

A 14-year-old boy in Irving, Texas named Ahmed Mohamed was taken into police custody after he brought a homemade clock to school. The boy, who, according to a piece in the Dallas Morning News, “makes his own radios and repairs his own go-kart,” wanted to show his engineering teacher his handiwork.

School officials originally thought his clock was a bomb and now are simply calling it a “hoax bomb.” ...

September 16th, 2015

# Ahmed Mohamed’s father has been an activist fighting for justice for muslims

The father of the 14 year old who was arrested for bring a science project to school. As is often a case, when a 14 year old shows courage in the face of injustice, they have a parent who has also been a crusader on political issues.

Mohamed also defended the Quran when pastor Terry Jones tried to burn it

In 2012, Florida pastor Terry Jones said he was putting the Quran on trial. Jones had threatened to burn the Quran ...

September 16th, 2015

In light of this weeks events, it is good to remember the time that school administrators used spyware on computers to spy on children even when the children were at home in their bedrooms.

The suit alleged that, in what was dubbed the “WebcamGate” scandal, the schools secretly spied on the students while they were in the privacy of their homes. School authorities surreptitiously and remotely activated webcams embedded in school-issued laptops the students were using at home. After the ...

September 16th, 2015

# Clean up your act with lein-checkall

I am a bit late but I’ve only recently become consistent about using a linter to check my Clojure style. And I’ve only today discovered the Leiningen plugin lein-checkall, which combines lein check && lein kibit && lein eastwood && lein bikeshed.

Venanti has written about the importance of these:

Eastwood

Eastwood is a Clojure linter, invoked with lein eastwood. As a general request, please use a linter. Some of my favorite moments in the last year have come from people trying to ...

September 15th, 2015

# Most cells in the body keep time

Very interesting:

Not that long ago, as Partch knew, it had become clear that nearly every cell in nearly every tissue in the body keeps time. Every 24 hours, responding to a biochemical bugle call, a handful of proteins assembles in the cell’s nucleus. When they bind to each other on the genome, they become a team of unrivaled impact: Under their influence, thousands of genes are transcribed into proteins. The gears of the cell jolt into motion, the tissue ...

September 13th, 2015

# Loyalty is the most desirable response, but also the hardest to quantify and design for

Interesting:

To remain healthy, a social product needs to establish loyalty, and to mitigate the natural responses to discontent with the state of things. The early adopters will be interested in voicing their opinion, but typically these discussions are only interesting to the early adopters. Giving them a single place to have meta-discussions keeps them happy, and prevents them from disrupting the experience of users who couldn’t care less.

Similarly, creating mechanisms that allow a user to exit without completely abandoning ...

September 13th, 2015

# Calculating and Visualizing Voronoi Diagrams using the Quad-Edge Structure – Alan Shaw

Allan Shaw talks about a data structure called a “quad edge”. There were a lot of ideas here that were new to me. The data structure keeps rotation as one value, and the orientation of the edge as one value, but anything like coordinates are kept in a field called “data”. This separates the topology from the geometry. There is also a “next” function to find the next edge. This, apparently, gives great advantage when calculating a whole network of ...

September 12th, 2015

# Microservies mean freedom of future action

Interesting:

In short, maximize future freedom of action. This heuristic also answers the when and why questions for microservices.

To prove it, let’s start with Sprott & Wilkes on SOA. Wait, Service Oriented Architecture? SOA is microservices loving parent. The philosophy trickles down:

When the service is abstracted from the implementation it is possible to consider various alternative options for delivery and collaboration models. […] It is entirely realistic to assume that certain services will be acquired from external sources because it ...

September 11th, 2015

# Why are microservices happening now?

The term “microservices” only goes back to 2013. I would have trouble saying why I love the style so much, except that I hated dealing with Ruby On Rails and the PHP framework known as Symfony. I was willing to deal with a lot to get away from the pain of those systems. The growth of great package managers also seemed to weaken the need for monoliths.

But Martin Fowler says the most important change was the move to Continuous ...

September 11th, 2015

# The difference between Clojure and Common Lisp

Fascinating bit by Giles Bowkett. This uses recursion and is how you would do it in Common Lisp:

(defn build [list-1 list-2] (if (nil? list-1) () (concat (map (fn [bubble] (list (first list-1) bubble)) list-2) ...

September 11th, 2015

# Microservices are different

It does feel like the world is moving closer to distributed IPC. We are not there, but the push toward microservices seems a step in that direction. The warnings of the past feel less relevant now.

When I wrote Patterns of Enterprise Application Architecture, I coined what I called the First Law of Distributed Object Design: “don’t distribute your objects”. In recent months there’s been a lot of interest in microservices, which has led a few people to ask whether microservices ...

September 11th, 2015

# The problem with Meetups

This is good:

Consider the meetup speaker. She’s had a topic in mind for while, and so when the request went out for speakers, she volunteered. But that was three months ago, and now the meetup’s only a few weeks away, and she hasn’t even begun. She starts to outline the talk, but can’t quite figure out where to start. She can explain all the details easily, but the order in which they should be introduced, the organizing structure of ...

September 11th, 2015

# Zach Tellman — the need for backpressure in queues, and the limits

This is very good. A lot of this interesting, but perhaps the biggest surprise is when he adds 16 consumers of tasks, but also 16 producers of tasks, the crisis point comes suddenly, compared to when there was only 1 consumer and 1 producer. With multiple consumers the consumption is averaged out, so each machine works fine right up to the moment of crisis.

His main theme is “Unbounded queues are fundamentally broken because it puts the stability of our ...

September 11th, 2015

# Dynamic scope in Clojure

The interesting thing here is that the dynamic vars are wrapped in functions, which makes them a bit safer than dynamic scope would imply.

Each of these sub-clauses is very similar to the parent structures, and can be arbitrarily nested. As such, it is most easily constructed with a recursive function. However, Clojure’s let bindings are lexical, and don’t extend into recursive calls. We could make the memoized gensym call a parameter, but since we also need a separate generator ...

September 11th, 2015

# This instance doesn’t do much, but it does have a nice property: it’s only equal to itself

This is a very clever hack:

Graphviz assumes explicit identities for nodes, so what about when we want to represent a tree? We can’t simply use the identity of the node, because the same value at different positions within the tree must be treated as separate nodes. One possibility is to represent each node as a tuple of its value and its position in the tree, but this forces us to consider how to represent positions, which is neither obvious nor ...

September 11th, 2015

# The 8 fallacies of distributed computing

This is great:

The IT group usually has different administrators, assigned according to expertise–databases, web servers, networks, Linux, Windows, Main Frame and the like. This is the easy situation. The problem is occurs when your company collaborates with external entities (for example, connecting with a business partner), or if your application is deployed for Internet consumption and hosted by some hosting service and the application consumes external services (think Mashups). In these situations, the other administrators are not even under ...

September 11th, 2015

# Stanislaw Lem’s dystopia

Stanislaw Lem’s vision of the future deserves more attention. I like this writer. I read Memoirs Found in a Bathtub which I thought was awesome.

I attended two more Singularity Summits, in 2008 and 2009, and during that three-year period, all the much-vaunted performance gains in various technologies seemed paltry against a more obvious yet less-discussed pattern of accelerating change: the rapid, incessant growth in global ecological degradation, economic inequality, and societal instability. Here, forecasts tend to be far ...

September 10th, 2015

# Free, white, and 21

Interesting:

And so, “free, white, and 21” was as much about power denied as asserted. Women used it more often precisely because their freedom was restricted. Men would use it too, whenever challenged. In That Certain Woman (1937), Henry Fonda tells of his desire to work up the courage to use the phrase against his domineering father. In real life, Henry Ford used it in 1919 to justify defying his stockholders. The saying was an assertion of will, of the rights ...

September 10th, 2015

# Is Gradle the best build tool for the JVM?

Gradle continues to innovate with new features.

Is Buildr dead? Buildr is now part of Apache and yet its last update was over a year ago. I tried to use Buildr this year but I ran into errors and when I searched on Google I found all of the advice was many years old. No one responded to my question on StackOverflow. I’m left thinking that Buildr is dying.

Gradle has an awesome bunch of plugins and the eco-system is growing. ...

September 10th, 2015

# No locks for performance under load with concurrency

Interesting:

It’s quite clear that the lock-free approach scales a lot better under contention. This follows our intuition because lock-freedom allows system-wide progress even when a thread is blocked. If one goroutine is blocked on an insert or lookup operation, other operations may proceed. With a mutex, this isn’t possible.

Matchbox performs well, particularly in multithreaded environments, but there are still more optimizations to be made. This includes improvements both in memory consumption and runtime performance. Applying the Ctrie techniques to ...

September 10th, 2015

# Use Specter to transform Clojure’s lists

Interesting:

To change the name of all the stations named “Barista” to “Coffee Master”, I can use a for comprehension:

(for [site sites station (:stations site)] (if (= (:name station) "Barista") (assoc station :name "Coffee Master") station))

But using Specter:

(->> sites (transform [ALL :stations ALL #(= (:name %) "Barista")] #(assoc % :name "Coffee Master")))

Now, this example is not actually doing justice to Specter. But in a previous (superseded) versions of the ...

September 10th, 2015

# Matthew Phillips makes the case of Clojure’s “for” comprehensions

I am lazy so I would probably handle this with “reduce” as I then have a free-form function in which I can do whatever I want. And yet, list comprehensions are more idiomatic. Their limits make it more obvious what the structure of data should be. And for deeply nested items, they can handle everything at once, rather than needing to do nested calls to “reduce”.

But you can also do it this way, using a list-comprehension in Clojure’s for ...

September 10th, 2015

# Prismatic’s Schema is better than Typed Clojure because it has coercions

Interesting:

One very useful feature of Prismatic/schema which core.typed does not have is called coercions. With this feature you can both validate your data structure and transform it to the desired state. This is particularly useful when validating input data from a database or ring request and doing all the string->int, kebab-casing etc in one step. The net effect being much less defensive code ‘on the other side’ of the coercer since you can rely on the exact shape of the ...

September 10th, 2015

# Why is microservices popular now?

This is a word that came out of nowhere and took over the industry.

I wrote a good essay about microservices a few months before the word was invented.

Martin Fowler came up with the word microservices a few months later. He said:

Microservice practitioners, usually have come from an evolutionary design background and see service decomposition as a further tool to enable application developers to control changes in their application without slowing down change. Change control doesn’t necessarily ...

September 10th, 2015

# Fortran still survives

Interesting:

When you actually take a look at the bulk of FORTRAN, it looks suspiciously like C — and it has C linkage. So, to me personally, I lump FORTRAN and C together in my head and then the question becomes “What real advantage does the switch to C++ from C have for you?”. You can find vast amounts of information on the web to answer that question :)

I have not known a single person in over a decade to ...

September 10th, 2015

# Ritual burial 3 million years ago?

Interesting:

The researchers who made the find have not been able to find out how long ago these creatures lived – but the scientist who led the team, Prof Lee Berger, told BBC News that he believed they could be among the first of our kind (genus Homo) and could have lived in Africa up to three million years ago.

Like all those working in the field, he is at pains to avoid the term “missing link”. Prof Berger says naledi could ...

September 10th, 2015

# Checkpoint and Restore In User Space (CRIU)

Interesting:

Luckily for us as we were investigating this possibility we ran into an incredibly ambitious open source project called Checkpoint and Restore in User Space (or CRIU for short). The name says it all. CRIU aims to give you the same checkpointing capability for a process tree that virtual machines give you for an entire computer. This is no small task and actually required changes to the mainline Linux kernel to pull off. The original goal of this project ...

September 10th, 2015

# Mutable versus Immutable history

What really happened? What is the state of your system?

Explaining the ideal behavior of our notebooks is relatively simple: regardless of how you enter or edit cells, it should show the results of executing the file from top to bottom: the same way node does. The easiest way to accomplish this of course is to just re-run the entire document from the start after every change. This is in fact how the “rewind” feature in works in bpython. Of ...

September 9th, 2015

# The conceptual clarity of CQRS

Interesting:

I found the cognitive load to be less than with other service based architectures I have worked on. I could jump into any area of the code base and because of the naming conventions for commands and events I could see what was going on – this has never been my experience with a service oriented architecture.

The main change in developer thinking that is necessary is that you don’t record state you record state transitions. Once that is internalised ...

September 9th, 2015

Relationships are difficult:

When I told this story to the man I love, I felt shame flooding me at the point when I’d said too much to stop yet hadn’t gotten to the worst part. I realized I made a mistake; I didn’t want him to hear about this. I started sharing because I was trying to explain what it feels like to pitch and write while I know this is what editors really want to run, what readers want ...

September 8th, 2015

# How to play cricket

Interesting:

You have two sides, one out in the field and one in. Each man that’s in the side that’s in goes out, and when he’s out he comes in and the next man goes in until he’s out. When they are all out, the side that’s out comes in and the side thats been in goes out and tries to get those coming in, out. Sometimes you get men still in and not out.

When a man goes out to go ...

September 7th, 2015

# Things that make Clojure beautiful: namespace declarations

In Python, and Java, the import statements at the top of the file are big jumble of disorganized statements. In Clojure the namespace declaration is a data structure that can be cleaned up using all the tools Clojure has for working on a data structure. Apparently that is the idea behind Slamhound, which detects when imports are not being used. That is clever. I did not know about Slamhound. I will have to check that out.

Also this:

which was ...

September 7th, 2015

I hardly know what to say. It’s like a lottery winner who later goes bankrupt. Twitter had such a fantastic opportunity. I recall, 5 years ago, when TechCrunch faced criticism for running so many stories about Twitter, but Michael Arrington defended the stories by saying that Twitter was important. And it could have been important. But now it is just fading away, thanks to mismanagement. They never should have gone after ad money. They should have built an eco-system around ...

September 7th, 2015

# Suicide on campus

Interesting:

Ms. Holleran was the third of six Penn students to commit suicide in a 13-month stretch, and the school is far from the only one to experience a so-called suicide cluster. This school year, Tulane lost four students and Appalachian State at least three — the disappearance in September of a freshman, Anna M. Smith, led to an 11-day search before she was found in the North Carolina woods, hanging from a tree. Cornell faced six suicides in the ...

September 6th, 2015

# The end of science

Awful:

Throughout the years, I have been discovering more and more of the inner workings of academia and how modern scientific research is done and I have acquired a certain degree of discouragement in face of what appears to be an abandonment by my research community of the search for knowledge. I found scientists to be more preoccupied by their own survival in a very competitive research environment than by the development of a true understanding of the world.

By creating ...

September 6th, 2015

# Video game as format for serious essay

Interesting:

For the uninitiated, That Dragon, Cancer (which has yet to see a retail release) is a narrative-driven game, meaning players walk slowly and click on elements in the game world to activate spoken passages of text and interactions with other characters. It stars the creator, Ryan Green, and members of his family, as they bounce between hospital rooms, days at the park, and weirder, out-of-body experiences. The film’s opening sequence appears to be taken from the game itself, putting ...

September 5th, 2015

# Is frontend Clojure development the best frontend development eco-system

I have not done much frontend work these last 3 years, so I am out of touch, but wow, there is a lot going on:

The first step is to define the routes we want. One of the designing features of bidi is that routes are data structures, not function/macro calls:

The app-routes ...

September 5th, 2015

# Limit the number of threads in Jetty

I do something similar, but I like the use of env, which I do not do:

(defn -main [& args] (let [config {:port (Integer/parseInt (or (env :port) "3000")) :join? false :min-threads (when (env :min-threads) (Integer/parseInt (env ...

September 5th, 2015

# A website with teacher reviews got a student suspended from school, in 1994

How can schools teach young citizens that they have the right of free speech, and yet then impose harsh punishments for free speech?

Fortunately, both my parents and everyone I talked to during my suspension (the length of which the school refused to define, but ended up being five days) were largely supportive of my cause. They argued (and I agreed) that what I had done was careless, and I could have avoided the whole mess in the first place by ...

September 5th, 2015

# Use ZeroMQ instead of Kafka

Considering how radically different these are, this is a funny comparison:

Stability was the key aspect of Kafka we were unhappy with after a yearlong journey with it.

An HA deployment of Kafka requires an HA deployment of zookeeper, which Kafka uses to coordinate distributed state and configuration. As I explained before, we’ve experienced a number of stability issues with this stateful cluster maintaining consistency through outages such as VM recycle. Some serious engineering time was going into reacting to issues, ...

August 31st, 2015

# It is very difficult to understand software based only on the database

And it is impossible to understand software if all you have is part of the database. I’ve had to struggle with this issue many times, at various companies. Apparently Annalee Newitz was bit by this as well.

The first thing I learned when I looked at the code was that the database Impact Team released on August 18, and on which I based my reporting about the number of active female users, was just a tiny portion of the ...

August 30th, 2015

# Racism is okay if the market approves? WTF?

Sickening:

Source

August 30th, 2015

# The financial bubbles of 2,000 BC

Another example of how science tends is biased toward excluding the possibilities of those things that would best explain our current situation, if we didn’t have the evidence, no one would be allowed to speculate such a situation:

The details of daily life are amazing, but another scholar, Gojko Barjamovic, of Harvard, realized that the archive also offered insight into something potentially more compelling. Many of the texts enumerate specific business details: the price of goods purchased and sold, the ...

August 30th, 2015

# Matrices are representations of linear transformations

A good intro to an amazing topic:

Source

August 30th, 2015

# Google won’t hire Max Howell even though Google depends on Max Howell

Interesting:

Source

August 29th, 2015

# Rich Hickey: Would you want to be on a team that only did what was easy?

A dangerous attitude: “I like this because its easy for me right now.” Rich Hickey talking at the Rails conference. In the obvious case, this is a wonderful criticism of Rails.

He asks if anyone would want to join the Foo Fighters if they were the Kazoo Fighters. What if they felt guitars and drums were hard, so they only played kazoos, because kazoos are easy?

We should make decisions based on the work we need to do, not because ...

August 29th, 2015

# Hashmaps are not simple

Interesting:

I was at this talk and I disagree with his fundamental statement that simple + simple = simple. I program in Ruby one of the biggest problems beginners make is not creating complex data structures where they are needed. Instead they pass around hashes of hashes of hashes. Why? Hashes are simple, they’re easy to understand and work with. Unfortunately this initial simplicity introduces unexpected complexity, things like deep dup and deep merge are now needed. Every part of ...

August 28th, 2015

# Police caught on tape talking about a woman

I agree with this:

Olivarius-McAllister didn’t, at first, hear the latter portion of the message, figuring it was just dead air. She forwarded it to her city editor, though, who did listen to the whole thing.

“He turned around the office and said, ‘These people are very opinionated about your body,’” Olivarius-McAllister said in an interview. “I thought he was joking. I listened to it and felt just utterly appalled.”

The Durango Herald was instrumental in helping current La Plata Sheriff Sean ...

August 27th, 2015

# The personal responsibility to build a durable ego

Interesting:

I do not suggest, of course, that all men lack these skills, but I am suggesting that many do, and that it manifests itself in various, troublesome ways. It seems to me that we must do a better job of teaching our children, especially our sons, that your ego does not own you and the world does not owe you. That a woman has the right to not be interested. That you might get fired. That your ex-wife might ...

August 27th, 2015

# Over budget and late: the BBC epic software fail

Sad that this goes on, and top management never seems to learn:

“Agile development was agreed upfront, not developing the whole system end-to-end from day one,” Linwood told MPs.

“Several months later [the business] decided it didn’t want to do that, but would wait for the full functionality; it didn’t want to continue down that path,” he said.

“The business objected to the [agile] approach. Small incremental releases would allow the business to get hands-on with the technology so it would not ...

August 27th, 2015

# Good writing is difficult

I don’t understand this. Sit at one’s typewriter, no matter the result, because writers are the same on all days? That is not even coherent. If the results vary day by day, then clearly the writer has different ability to deliver on different days.

“All writers know that on some golden mornings they are touched by the wand — are on intimate terms with poetry and cosmic truth. I have experienced those moments myself. Their lesson is simple: It’s a ...

August 26th, 2015

# Zach Tellman: the heuristics of the government fail and the heuristics of software fail

Zach Tellman gives a speech that almost compares urban planning to writing software. He never exactly states his idea, but he is often on the brink. He compares the state and the nomad and suggests that the state is attempting to force reality to conform to a simplified version of itself, so as to make it tractable. He never exactly says “All of your attempts to write software are doomed” but that is implied by his implied criticism of the ...

August 26th, 2015

# Garajeando takes on the Gilded Rose Kata in Clojure

I dislike this line:

not-conjured-item-name (clojure.string/replace name #”Conjured ” “”)

Seems like calling “update” twice could be done with the opposite of this test:

(if (.contains name “Conjured”)

How to find the name of the unconjured item? I agree that is a tough issue.

For something this short, perhaps it doesn’t matter, but if this was non-trivial software, I would store a “:conjured” key in “items” and match against that. Seems less fragile than matching against a string. ...

August 26th, 2015

# Stuart Sierra’s anti-patterns for Clojure

This is a subtle difference:

If the operation requires a collection, then pass it a collection every time.

A “helper” like wrap-coll saves you a whopping two characters over just wrapping the argument in a literal vector, at the cost of lost clarity and specificity.

If you often forget to wrap the argument correctly, consider adding a type check:

(defn process-batch [items] {:pre [(coll? items)]} ;; ... )

If there actually are two distinct ...

August 26th, 2015

# Hauptsatz is the central result establishing the significance of the sequent calculus

An interesting preliminary for sequent theory. I’m interested because of my interest in Shen.

The cut-elimination theorem (or Gentzen’s Hauptsatz) is the central result establishing the significance of the sequent calculus. It was originally proved by Gerhard Gentzen 1934 in his landmark paper “Investigations in Logical Deduction” for the systems LJ and LK formalising intuitionistic and classical logic respectively. The cut-elimination theorem states that any judgement that possesses a proof in the sequent calculus that makes use of the cut ...

August 26th, 2015

# Less than 1% of female accounts on Ashley Madison showed any activity

Interesting:

Those millions of Ashley Madison men were paying to hook up with women who appeared to have created profiles and then simply disappeared. Were they cobbled together by bots and bored admins, or just user debris? Whatever the answer, the more I examined those 5.5 million female profiles, the more obvious it became that none of them had ever talked to men on the site, or even used the site at all after creating a profile. Actually, scratch that. As ...

August 26th, 2015

# Natural language processing (NLP) is a messy and difficult affair

Interesting:

Similar words are nearby vectors in a vector space. This is a powerful convention since it lets us wipe away a lot of the noise and nuance in vocabulary. For example, let’s use gensim to find a list of words similar to vacation using the freebase skipgram data6:

from gensim.models import Word2Vec fn = “freebase-vectors-skipgram1000-en.bin.gz” model = Word2Vec.load_word2vec_format(fn) model.most_similar(‘vacation’)

# [('trip', 0.7234684228897095), # ('honeymoon', 0.6447688341140747), # ('beach', 0.6249285936355591), # ('vacations', 0.5868890285491943), # ('wedding', 0.5541957020759583), # ('resort', 0.5231006145477295), # ('traveling', 0.5194448232650757), # ('vacation.', 0.5068142414093018), # ('vacationing', ...

August 26th, 2015

# Men cite their own work more than women cite their own work

Interesting:

But the new study (while confirming the 2013 work) is much larger and crosses many disciplines. This one is based on an analysis of 1.6 million papers written from 1950 to the present in the scholarly database JSTOR. While some first names are not gender exclusive, the study looked at first names that correspond with either men or women, but not both, at least 95 percent of the time, according to various public records. Papers written by people with names ...

August 24th, 2015

# She never did anything useful, she just raised her children

Ouch! That is some harsh misogynist burn from Jay Yarow:

Maria Wood was a book keeper for Microsoft, and married to another one of the early Microsofties in the picture. She left the company just two years later, suing it for sexual discrimination. Microsoft settled the case. After that, it doesn’t look like she did much else. She raised her children and became a volunteer.

Clearly she was a worthless nobody who never did anything useful because she raised kids and ...

August 23rd, 2015

# Why use Clojure at your startup

I guess these are becoming the standard set of answers?

The specific design decisions and abstractions in clojure which I expect to minimize costs are the following:

Immutability. Engineering is a super giant rubics cube. To solve it, you need to know each moving part. When you get all the moving parts to finally be in the correct locations and move together, that’s when you’ve solved it. Immutable data structures don’t move. The less moving parts you have, the more brainpower ...

August 23rd, 2015

# E.W.Dijkstra on multi process systems

There was some moment, in the late 1960s and early 1970s, when the field of computer science hit a happy fluid moment. By that point, a large number of people had been working with computers for 20 years, so they knew what worked and what did not work, and yet nothing had been settled yet, no architectures dominated. And then, suddenly, computers became a monoculture with standard parts:

1.) a CPU

2.) random access memory

3.) a storage device such as a ...

August 23rd, 2015

# Can the economics profession ever be made whole?

Paul Romer is doing heroic work trying to understand what happened to the economics profession:

I had a twitter exchange with Luis Garicano that was prompted by that post. It illustrates what my private conversations have been like.

To make this exchange more readable, I have tried to order it in threads, with each response indented just below the tweet that seems to have prompted it. As a result, the order of the tweets is slightly different from the actual chronological order. ...

August 23rd, 2015

# What politicians deserve respect?

The USA has been in debt since 1835. Rand Paul can ask for a world in which governments run debts, but isn’t that a bit of fantasy? If your hopes for the world run so far from what is real, at what point should the public treat you as a novelist? Much of what Stephen King writes is close to reality than what Rand Paul talks about, so should we think of Stephen King as qualified to prescribe economic ...

August 23rd, 2015

# C. A. R. Hoare in 1973

I am surprised at how little has changed since 1973:

I would like in this paper to present a philosophy of the design and evaluation of programming languages which I have adopted and developed over a number of years, namely that the primary purpose of a programming language is to help the programmer in the practice of his art. I do not wish to deny that there are many other desirable properties of a programming language, — for example, machine independence, ...

August 23rd, 2015

# The Starbucks scam

This would work on the YC application where they ask “Tell us something other than computers that you have hacked”.

There is a man who comes to my Starbucks every single day and orders the most horrible drink in an infuriating way. He purchased 365 Starbucks cards and registered every one of them online with a different birthday so that he gets a “free birthday drink” EVERY DAY OF THE YEAR. Even though I know exactly how he “beat the ...

August 23rd, 2015

# Pretty in kindergarten

Life is complicated:

And yet, here we are in the actual world as it is, are we not? Just this morning I was getting my five-year-old daughter dressed for kindergarten. She wanted to wear a new dress we hadn’t really tried on at the store; I’d just held up to her quickly to size it up and move along. Putting it on, I realized it was kind of big. It looked nothing like the cute little Jackie-O style number I’d ...

August 22nd, 2015

# Paul deGrandis in 2012, the emergence of Clojure success stories

I like this talk by Paul deGrandis because he says he is not an Enterprise guy, he is a startup guy, and he says Clojure is more a startup technology than an Enterprise technology. I like that because I work with startups. Some people say that Clojure is best as Clojure In The Large, but I don’t work in the large. He says Enterprise CTO’s are driven mostly be fear.

Clojure is great for building a prototype that can become ...

August 22nd, 2015

# Influences in 進撃の巨人 (Attack On Titan)

I watched the first 5 episodes of 進撃の巨人. I thought I could pick out a few dozen influences that get recycled in this animae. Some are old Japanese obsessions, such as invasion by powerful outsiders. Some seemed more international.

It starts with humans living behind walls. They live in a village that is of Franco-Germanic design, and the people dress in a similar fashion. The people and the village are straight out of Bruegal painting.

The people are cut off ...

August 22nd, 2015

# Camille Fournier (Rent the Runway) – Consensus Systems for the Skeptical Architect

ZooKeeper owns your availability. Worth watching. I thought it was amazing when she said that even 5 years ago, even at Google, most programmers were not thinking in terms of distributed computing. Instead, its been the boom in microservices that has driven the adoption of distributed computing. I wonder why microservices wasn’t more popular 10 years ago? Everything in software started off monolithic and has gotten smaller. I suppose that is because of the increasing ease of composition?

Source

August 22nd, 2015

# A good society is safe for children

I think this image is meant sarcastically, but I find that I 100% support all of the slogans:

Traffic safety is an important issue. In the USA, most homes open directly onto a street, or they have a yard, which touches upon a street. This is insane. There should be 100 meters between any house and any car. We should not be telling children “Don’t play in traffic”, we should, instead, redirect traffic so it never comes close to any ...

August 20th, 2015

# Concurrency is easier with Clojure

I’m helping a co-worker write concurrent code in Java. I’m reminded, once again, that Clojure is easier. In Java, we must wrestle with the issue of synchronized blocks. We have an operation that reads a value from a hashmap and then deletes the key from the hashmap. We are using the hashmap almost like a queue: many threads might read from this hashmap, and yet we only want one thread to read from this hashmap. Therefore, both the read and ...

August 20th, 2015

# SSL for Jetty via Apache reverse proxy

I found this to be useful

<VirtualHost *:443> SSLEngine on (...) ProxyRequests Off ProxyVia Off ProxyPreserveHost On AllowEncodedSlashes NoDecode RequestHeader set X-Forwarded-Proto https RequestHeader set X-Forwarded-Port 443 <Proxy *> Order deny,allow Allow from all </Proxy> <Location /test> ProxyPass http://localhost:8666/test nocanon </Location> (...) </VirtualHost> Source

August 20th, 2015

# How to create a POJO in Clojure

The premise sounds interesting:

Those times you need to have Java APIs.. Some of these APIs need to return data. In Clojure it is usually a map:

{:q “What is..?” :a 42}

In Java it is not that simple for several reasons.. Java maps are mutable, there are no idiomatic tools to inspect, destructure them, Java (programmers) like different types for different POJOs, etc..

I would have appreciated an actual example. The great thing about Clojure is how it makes data access easy. ...

August 20th, 2015

# SalesForce is confusing

Reading through SalesForce documentation I constantly come upon 404 errors:

They don’t keep the documentation up to date.

SalesForce has so many products that it is difficult to figure out which bit of documentation applies to whatever it is that you are trying to do.

Consider the question, “When does it make sense to add a Connected App to a Managed Package?” This is something I’ve wondered. And no one can give me a reliable answer.

August 20th, 2015

Interesting:

In Camille Fournier’s excellent talk on consensus systems, she advises that “Zookeeper Owns Your Availability.” Consensus systems are a necessary and powerful tool, but they add complexity and new failure modes. Specifically, if the consensus system goes down, you can’t do work any more. In Chronos’s case, you’re not just running one consensus system, but three. If any one of them fails, you’re in for a bad time. An acquaintance notes that at their large production service, their DB ...

August 20th, 2015

# Bad habits: someone reports a bug so you insult them

This is a good example of how to do things wrong. Kyle Kingsbury did another one of his epic posts on Jespen. Every one of his posts so far has been a masterpiece of technical investigation. In the latest article he found a bug in Chronos, and he created an “issue” on Github. One of the programmers of Chronos then insulted him.

Kyle Kingsbury says:

I’m still not clear how exiting preserves correctness and prevents “split brain behavior”, but I’ve ...

August 11th, 2015

# Alexis Neiers: I wasn’t wearing Louboutins

Alexis Neiers Phone Call (Full Scene) by tbhuratchet

Source

August 11th, 2015

# Insider trading is the best way to steal

Interesting:

Today’s big hacker insider trading charges are utterly amazing. Here are the news release and criminal complaint from New Jersey federal prosecutors, the Brooklyn federal criminal complaint, and the SEC news release and civil complaint. The gist is that some guys in Ukraine allegedly hacked into the servers of the big newswire companies (Marketwired, PR Newswire and Business Wire) and stole press releases, and then gave them to some other people to trade on. That right there: That is the ...

August 11th, 2015

# What poor and uneducated brilliance looks like

There must be a lot of this now, and it must have been much worse in the past, people of intelligence who lived without education, and died in poverty:

Unlike all of Havard’s other correspondents Virginie wrote almost entirely in the local langue d’oïl dialect, Gallo. This may have been a daily language of communication in the region but there was almost nothing in print available at the time. In effect Virginie had to invent her own orthography and ...

August 11th, 2015

# Redis Out Of Memory error

Interesting:

I’m getting “OOM command not allowed” when trying to set a key, maxmemory is set to 500M with maxmemory-policy “volatile-lru”, I’m setting TTL for each key sent to redis.

info command returns : used_memory_human:809.22M

If maxmemory is set to 500M, how did I reached 809M ? Info command does not show any Keyspaces , how is it possible ? keys * returns “(empty list or set)” ,I’ve tried to change db number , still no keys found. Here is info command output:

redis-cli -p 6380 ...

August 11th, 2015

# The wrk command replaces Apache Bench

Apache has long had a strange gap in its testing tools. There was “bench” and there was “flood”. bench is easy but only handles HEAD requests. flood can do everything but requires a complicated XML config.

Now the team at Netty have spun off the wrk command, which looks very useful:

wrk - a HTTP benchmarking tool wrk is a modern HTTP benchmarking tool capable of generating significant load when run on a single multi-core CPU. It combines ...

August 10th, 2015

# The assumption you are smarter than everyone else

Interesting:

I’ve noticed a common bias that shows up in some founders: they believe that their competitors are stupid or uncreative. They’ll look at other businesses and identify inefficiencies or bad systems, and decide that those conditions exist because of dumb decisions on the part of founders or employees.

This is a bad belief to hold. In truth, competitors in the market are usually founded and run by intelligent people making smart and logical decisions. That doesn’t mean that all the ...

August 9th, 2015

# When the FDA gets it right

Frances Kelsey, a Hero During the Thalidomide Scourge, Dies at 101

I suppose we could find it worrisome that when a bureaucrat gets it right, people are so astonished that they award a medal to the bureaucrat. But I admire courage, and I realize it takes courage to stand up to a product when both government and business are for it, and for that reason, I believe she deserves to be remembered as a hero.

Source

August 8th, 2015

# Dogmatism Skepticism Eclecticism

Interesting:

In a paper delivered to the Aristotelian Society on 12 March 1956,[1] Walter Bryce Gallie (1912–1998) introduced the term essentially contested concept to facilitate an understanding of the different applications or interpretations of the sorts of abstract, qualitative, and evaluative notions[2]—such as “art” and “social justice”—used in the domains of aesthetics, political philosophy, philosophy of history, and philosophy of religion. Garver (1978) describes their use as follows:

The term essentially contested concepts gives a name to a problematic situation that many people ...

August 7th, 2015

# A package gets sent over the ocean 7 times by FedEx

Interesting:

Source

August 6th, 2015

Interesting:

Google Plus was done differently to other innovations in Google. It was set up as an autonomous unit in a separate building with thousands of engineers moved to it. The CEO, Larry Page, moved his office into that new building to signal its importance and to ensure that it could operate without constraint. And that is precisely what it did. It innovated quickly and, in the process, had the rest of the organization perplexed, concerned and wondering what it ...

August 6th, 2015

# Risk aversion is destroying modern movie making in the USA

Interesting:

This byzantine plot sprawl has been in full effect this year. Avengers: Age of Ultron lost many round about the point the villain heads off to a South African shipyard in search of something called Wakandan vibranium. Promoting the film, writer-director Joss Whedon acknowledged that keeping all the narrative plates spinning for his six-man superhero team, plus all the side players, had left him “a little bit broken”. Terminator Genisys director Alan Taylor, faced with the collective “eh?” over his ...

August 5th, 2015

# The basics of working with Supervisord

I’ve come up with a system whereby:

1.) Jenkins pulls our code from the master branch on Github

2.) I wrote a build script that I store in /usr/local/bin

3.) Jenkins calls the build script as one of its build steps

4.) I wrote a script that finds the PIDS of existing instances of the app, and kills them:

#! /bin/sh ps aux | grep SSAM | awk '{print $2}' | xargs kill 5.) Jenkin calls the kill script as its last build step 6.) ... Read More Source August 5th, 2015 In Business No Comments # Opfer müssen gebracht werden Interesting: Lilienthal was a German mining engineer who, starting with only a pair of birdlike wings, designed and flew a series of gliders—eighteen in all—and made more than two thousand flights in them to become the first true aviator. He held on to a connecting bar with his legs dangling free so they could be used in running or jumping and also in the air for balance. He took off by jumping from a building or escarpment or running down a ... Read More Source August 4th, 2015 No Comments # Supervisord is Python A reminder to myself, liking Supervisord entails liking Python idioms: A [program:x] section actually represents a “homogeneous process group” to supervisor (as of 3.0). The members of the group are defined by the combination of the numprocs and process_name parameters in the configuration. By default, if numprocs and process_name are left unchanged from their defaults, the group represented by [program:x] will be named x and will have a single process named x in it. This provides a modicum of backwards compatibility ... Read More Source August 2nd, 2015 No Comments # Ultra-Orthodox Jewish man recently released from prison kills at Gay Pride in Israel I suppose hate never goes away, it just finds different subjects to focus on, during different eras. Sixteen-year-old Shira Banki died on Sunday, a spokeswoman for the Hadassah Medical Center said. Her organs will be donated. Six people were wounded Thursday by Yishai Schlissel, an ultra-Orthodox Jewish man recently released from prison. Haaretz reports that Schlissel had been serving a 10-year sentence after comitting a similar attack at the 2005 pride parade, when he stabbed three people. Source August 1st, 2015 No Comments # The humility of the Clojure community Very true: I was bragging to Alan about a Drake release, which I was calling 0.2.0. Alan rolled his eyes. He was like, “Considering the conventions put forth by Semantic Versioning, and considering that Drake has been in production at this company as well as other companies for years now, why not call it version 1 already?” I pushed back a bit, by surveying two existing open source Clojure projects I know of: Aleph, Zach Tellman’s notorious asynchronous library for ... Read More Source July 31st, 2015 No Comments # Fatherhood circa 2015 Regarding Millenial Men Aren’t the Dads They Thought They’d Be. Short-term waves ride on top of long-term waves, but if we want an accurate picture of reality, we need to simultaneously remember the short-term and long-term waves. The trough of one wave can mitigate the peak of another wave, should their frequency be off in such a way that they interfere with each other. Likewise, with social trends. Any article about what men think about marriage and fatherhood should be juxtaposed ... Read More Source July 31st, 2015 No Comments # But you can customize the code? Mike Knepper says Ruby gems are dangerous, but I am ambivalent: The real problem with Devise commandeering all these components is that it makes the system extremely rigid. If the business logic changes (and yes, it will change) in a way that affects user sign-in or account creation, the developer is limited to modifying the app within the constraints of Devise. The developers behind Devise may not have anticipated a situation quite like yours, so getting Devise to work with the ... Read More Source July 31st, 2015 No Comments # Refactor async work in Ruby Kevin Buchanan makes an interesting point: But, that’s starting to seem like a lot of behavior, and maybe that behavior is crucial enough to our application that we want to have more control over it, or want one place to go to change how we retry asynchronous tasks in our application. If we consider this retry, backoff, failure logic a key feature of our app, we probably don’t want to be coupled to using Sidekiq for this. What if tomorrow ... Read More Source July 30th, 2015 No Comments # Innovation has slowed since the 1970s Interesting: “Real rocket science” took place almost 50 years ago, with the Apollo moon landing. The Apollo missions set the speed record for humans at roughly 40,000 km/hour. But after that, the rocket science advances started to slow down. From 1685 on, the number of scientific papers published doubled every fifteen years—he likened it to Moore’s Law—but that leveled off in the 1970s. Who was doing this rocket science, he asked; who was programming these rockets and spacecraft to land on the ... Read More Source July 29th, 2015 No Comments # Could I ever explain monads to someone else? I would like to get to the point where I feel comfortable explaining monads to others: In functional programming, a monad is a structure that represents computations defined as sequences of steps: a type with a monad structure defines what it means to chain operations, or nest functions of that type together. This allows the programmer to build pipelines that process data in steps, in which each action is decorated with additional processing rules provided by the monad.[1] As such, ... Read More Source July 28th, 2015 No Comments # When to use repeating tasks inside of an app? I would guess the best thing about cronj is its focus on thread management. And yet, I am in favor of very small apps, which may only have a single task that repeats. But this raises problems for the JVM. If I bundle all tasks into a single JVM process, then the highly optimized JVM engine can take full advantage of the careful thread management of cronj. If I have separate apps, then they compete for resources (though the newest ... Read More Source July 28th, 2015 No Comments # Why Docker failed Interesting: Building container images for large applications is still a challenge. If we are to rely on container images for testing, CI, and emergency deploys, we need to have an image ready in less than a minute. Dockerfiles make this almost impossible for large applications. While easy to use, they sit at an abstraction layer too high to enable complex use-cases: Out-of-band caching for particularly heavy-weight and application-specific dependencies Accessing secrets at build time without committing them to the image Full control over ... Read More Source July 28th, 2015 No Comments # Trying to convince devs of the merits of Clojure Interesting: Leon Grapenthin: I have tried various different approaches from convincing of Clojure advantages in the Java devs concrete domain, showing off incredibly awesome toy projects, larger projects, not tryng to sell, trying to sell, sending ClojureTV videos and what not approach you can think of. I have not managed to introduce one Java dev to Clojure in a way that he picked it up and had no interest before. I have spent many hours thinking about how I could ... Read More Source July 28th, 2015 No Comments # The limits of RESTful interfaces Interesting: The chart leaves most of the rows blank for the year 1995, but of course, all of the necessary technologies existed in 1995, and in 1989. The focus of the article is on HTTP, but the article might be stronger if it confronted why HTTP was successful, when it lacked important abilities such as Authentication. There were other technologies that offered Business Logic and Logging and Realtime, back in 1989, so why weren’t they more successful? It’s also curious ... Read More Source July 28th, 2015 No Comments # Mutable arrays in Clojure Chris Zheng has done some impressive work with mutable arrays: Predicates as Datastructure I’m quite proud of the expressiveness of the ova syntax. We can see below the number of possible ways that we can select elements out of the array. Here is just a sample of what can be done using the select function. (def ov (ova [{:val 1} {:val 2} {:val 3} {:val 4} {:val 5} {:val 6} ... Read More Source July 27th, 2015 No Comments # When should Clojure imitate Object Oriented Programming? Chris Zheng writes: Servers that are running on a particular port can be tracked and stopped. I have to say, this was the feature that I wanted the most, which motivated the framework’s design. The annoying thing about development in emacs is that I have to be careful of not losing the reference to the server. Since there was no way of stopping it unless the repl is restarted. I wanted to implement a registery for references to running servers ... Read More Source July 26th, 2015 No Comments # The maybe monad represents computations whose result is maybe a valid value, but maybe nil Here is a sentence I have read a dozen times without understanding it: The maybe monad represents computations whose result is maybe a valid value, but maybe nil. This seems like a good way to think about the Any type, when dealing with things such as Typed Clojure. Source July 26th, 2015 No Comments # The sins of Adam Bard This last year I find that everything Adam Bard writes is worth reading. I have not been checking his blog very often but I should. I just saw this post from a year ago, which is really fantastic: Any time you put a let in a let or an if in an if, that’s a strong code smell. It means you’re still writing code in a way that requires you to short-circuit your functions with returns. There is a fascinating debate ... Read More Source July 25th, 2015 No Comments # Scheduling libraries in Clojure Chris Zheng has some interesting arguments for his particular take on these issues: There are now many more scheduling libraries in the clojure world: at-at chime clj-cronlike cron4j monotony quartzite schejulure With so many options, and so many different ways to define task schedules, why choose cronj? I have listed a number of design decisions that make it beneficial. However, for those that are impatient, cut to the chase, by skipping to the simulations section. …In reviewing other scheduling libraries, it was found that fully-featured thread management capabilities were ... Read More Source July 25th, 2015 No Comments # Will I regret Functional programming? I’ve spent the last year writing negative things about Object Oriented Programming, and I’ve been among the many people arguing that Functional Programming is the future. And I’ve talked about the political forces that drove the adoption of Object Oriented Programming. But that does raise the issue, what political forces are driving the adoption of Functional Programming? One possible answer is “None” and that would explain why Functional Programming remains a small niche compared to Object Oriented Programming. Another is ... Read More Source July 24th, 2015 No Comments # Why Python 3.x went off course A fascinating post from 2005, which is when Python began to veer off course. Python 2x had some beautiful features that could have been further developed, but instead, with 3.0, Python went down the classic Object Oriented road. In this post, Guido van van Rossum explicitly rejects much of the Functional paradigm that Python had picked up from Lisp. So now reduce(). This is actually the one I’ve always hated most, because, apart from a few examples involving + or *, ... Read More Source July 24th, 2015 No Comments # They cost of using Hystrix Ouch! We cannot use Clojure’s concurrency primitives (futures/promises/agents). That is fascinating to think that at some point Clojure’s concurrency primitives are not enough, and so we need to give up on them and move to a Java library. I am aware that Netflix is dealing with unusual scale, but what is the point of Clojure if it doesn’t automate exactly these issues? The comments are interesting: Marc: When using Aleph, the choice for lamina would seem a sure thing. What made you turn ... Read More Source July 24th, 2015 No Comments # The simplest step toward circuit breakers in Clojure I think I missed the importance of this the first time I read it: Consider you have this line within a service response: {:body @(future (client/get “http://soundcloud.com/blah/wah”)) :status 200} Now http://soundcloud.com/blah/wah goes down and those client requests start getting blocked on the request. In Clojure all future calls acquire a thread from the same thread pool. In our example the service is blocked up, is pilling new requests onto the blocked pool and we are in trouble. My first solution to this problem ... Read More Source July 24th, 2015 No Comments # Chris Zheng is consolidating his libraries into Hara I have some questions for Chris Zheng. I admire Ribol very much, though I was not aware of some of the other repos. I am curious why you are moving forward with an integration of these libraries? The Clojure community has so far avoided frameworks and even large libraries have met with rejection. What do you hope to gain by consolidating these projects? The projects: iroh has been moved to hara.reflect ova has been moved to hara.concurrent.ova cronj has been superceded by ... Read More Source July 24th, 2015 No Comments # Advice columns still survive in newspapers I am surprised that advice columns are still surviving in newspapers. Of course, I’m also surprised that newspapers still exist. Carolyn Hax offers relationship advice at the Washington Post: You probably don’t want to hear it, and I certainly don’t like saying it to someone who is engaged, but you don’t sound terribly well suited to each other. All relationships involve some accommodation, but not so much that you feel like you have to draw and hold awkward lines just because ... Read More Source July 24th, 2015 No Comments # Property based testing in the Functional Paradigm Interesting: Which brings me to another killer feature of many functional languages: property-based testing (PBT). While PBT is by no means an exclusive domain of functional languages, it does have deep roots in Haskell in the form of QuickCheck. What sets PBT apart from its traditional unit and integration brethren is its emphasis on defining a set of properties that describe a function and ability to generate a lot of random test cases to attempt to falsify these specifications. This ... Read More Source July 24th, 2015 No Comments # Functional programming is not the same as static typing I like this article, but it does confuse Functional Programming with static data types. Consider this example of evil Ruby code: Take for instance the following Ruby code that uses Virtus. class Events < Array def Source July 24th, 2015 No Comments # Dealing with mutation is hard Obviously, I agree with this: Dealing with mutation is hard. When I constantly grappled with these issues early on in my career, I thought I had serious issues. Perhaps I wasn’t cut out to be a developer. Maybe I should seriously consider a different career. It didn’t help that other developers breezed through similar assignments as if mutation and them were one (don’t get any ideas). But then I started reading about functional programming and how everyone was endlessly whining about ... Read More Source July 24th, 2015 In Business No Comments # Women still get fired for being pregnant I find it sad that in the year 2015, women still get fired for being pregnant: Juarez’s complaint also claimed that the company has a “glass ceiling” that keeps women from getting promoted. Just 10 of the 98 stores in the San Diego area where she worked had female managers. And at trial, a former district manager testified that a vice president reprimanded him for having so many women in management positions, telling him, “What are we running here, a boutique? ... Read More Source July 23rd, 2015 In Business No Comments # Robyn Exton keeps moving forward I’ve been surprised that so many dating sites were started by men, and so few by women, so this is an interesting story: Her, the queer dating app for women, has today announced that it will be available nationwide. Her is a dating app that puts a strong focus on content, specifically curated for and dedicated to queer women, whether they’re bi-curious or as gay as a rainbow. Her was previously available in seven cities across the country, only activating those ... Read More Source July 21st, 2015 In Business No Comments # Hollywood sexism Interesting: The actress told Radio Times: “I think it’s still completely shit actually. I don’t think there’s any appreciable improvement and I think that for women, the question of how they are supposed to look is worse than it was even when I was young. So, no, I am not impressed at all.” Thompson was much more optimistic about the movie business way back when, she says: “When I was younger, I really did think we were on our way to a better world ... Read More Source July 21st, 2015 No Comments # Men who lose at video games are the most likely to harass women Interesting: That should sound a whole lot like a lot of other, frequently sexist online spaces: Think Twitter. Or Reddit. Or 4chan. In each of these environments, Kasumovic suggests, a recent influx of female participants has disrupted a pre-existing social hierarchy. That’s okay for the guys at the top — but for the guys at the bottom, who stand to lose more status, that’s very threatening. (It’s also in keeping with the evolutionary framework on anti-lady hostility, which suggests sexism is ... Read More Source July 21st, 2015 In Business No Comments # The rebirth of urbanism Interesting: Multi-unit buildings are making a comeback. Construction is now at the best level in 30 years. It’ll be curious how far this trend goes. And this about the death of the office park: The American ghost town has assumed different forms: the abandoned gold-rush towns out West, the silent Floridian subdivisions of underwater McMansions. Now, we have fiefdoms of mid-Atlantic office space, on streets named Research Boulevard and Professional Drive, thinning out in the sprawl. They are hobbled by changing work ... Read More Source July 19th, 2015 No Comments # When is it ethical to out someone? Interesting: Everyone’s feeling very proud of themselves today for being grossed out by a Gawker post containing the text and email exchanges between a male escort and a well-connected, married executive who was trying to procure said escort’s services. The issue at hand, according to everyone who’s outraged, is that this is the outing of a gay man who would otherwise have been living a closeted life with his wife and three kids, harming no one. Because he is not ... Read More Source July 16th, 2015 No Comments # The worsening web The comments here are great: Let’s dive deeper into the CNN article. Among the 200+ HTTP requests the page makes are calls to 25 different domains. Yes you read that correctly. TWENTY…FIVE. Among them are a few that are clearly ad related (ex. ad.doubleclick.net, pixel.moatads.com), a few that serve some analytics function, and many whose names are intentionally obfuscated to confuse us. Jeff Edsell: The part of web cruft I hate most: “Why does our page load so slow? Should you compress the images ... Read More Source July 16th, 2015 No Comments # Greg Hendershott looks at Racket Macros I wanted to ask Greg Hendershott for permission to copy his code in Clojure, but I could not find an email address for him. My own email is lawrence@krubner.com. I love this epilogue from Greg Hendershott: "Before I had studied Chan (Zen) for thirty years, I saw mountains as mountains, and rivers as rivers. When I arrived at a more intimate knowledge, I came to the point where I saw that mountains are not mountains, and rivers are not rivers. But ... Read More Source July 15th, 2015 No Comments # Vim has a function with 400 lines of code When I worked at Category4, they had a homegrown HTML library. The method that generated HTML tables was over 1,100 lines of code (not a typo). So I’ve seen some fairly large functions. Dealing with them is why I now prefer 5 line functions written in a clean language like Clojure. This is interesting: This function is over 400 lines and contains over 40 #ifdefs. Its job? To wait for keyboard input. Several factors caused this code to be so ... Read More Source July 15th, 2015 No Comments # Sydney Leroux’s fake eyelashes Interesting: Everywhere I go, people are talking trash about Sydney Leroux’s fake eyelashes. To be fair, I’ve been in Canada, where she’s particularly reviled. I get it, she turned her back on you, Canada. You’re hurt. But through the pain, I beg you, do not bring her eyelashes into this. Because let’s be real: those eyelashes are amazing. Female soccer players have long balanced their athleticism and femininity. And at least in the United States, they’ve long balanced it the same way, ... Read More Source July 15th, 2015 In Business No Comments # Debt relief and devaluation as wild-eyed radical ideas? I notice this too. Ideas that were once the bedrock upon which Conservatives organized their economic thinking are now regarded as left wing: I continue to be amazed by how many people regard debt relief and devaluation as wild-eyed radical ideas; of course, it matters most that so many influential people in Europe share this ignorance. Anyway, for the record (and for my own future reference) I thought it would be helpful to post what Milton Friedman and Irving Fisher ... Read More Source July 15th, 2015 No Comments # What does the word “Cancel” mean? Some of the worst User Interface Design I’ve seen in awhile. The Amtrak website uses “Cancel” as the text on the button that cancels your reservation. Almost everywhere in the world, if you see a button that says “Cancel,” it means you do not want to do something. But Amtrak uses it here, so if you do want to cancel your reservation, you have to hit the Cancel button. Source July 2nd, 2015 No Comments # Ronda Rousey Fights Like An A Very Unusual Human Interesting: The story below was written before Saturday night’s fight in Rio de Janeiro, in which Ronda Rousey knocked out Bethe Correia in 34 seconds. That means Rousey is 12-0, and 6-0 in the Ultimate Fighting Championship (UFC), the biggest promotion company. Rousey has now won nine of her fights by armbar submission and three fights by KO/TKO, and remains the best pound-for-pound female MMA fighter in the world. ——– Ronda Rousey is the rare athlete who dominates her sport while transcending ... Read More Source June 23rd, 2015 In Business No Comments # David Tuite offers bad interview advice David Tuite writes: Expressing confusion in an interview doesn’t make you appear dumb. In reality it’s quite the opposite. This is terrible advice. The advice is common, but it is wrong. Multiple studies show that your questions can have a subconscious effect on the person interviewing you. Even if they say “Please feel free to ask questions” if you phrase the question the wrong way, or ask a question outside the bounds of what they were expecting, it becomes a ... Read More Source June 21st, 2015 In Business No Comments # CRM for startups SalesForce and SAP rule the world when it comes to enterprise CRM. Both are abominations. Bridget of TheyCay.com recently told me about 2 that are aimed at startups. I know nothing about these, so I’m just posting links for now, I hope to come back and investigate these more later. Pipedrive: Streak: Source June 21st, 2015 No Comments # Image recognition: we can not get there from here with what we’ve got Interesting: Leopards (or jaguars) are complex 3-dimensional shapes with quite a lot of degrees of freedom (considering all the body parts that can move independently). These shapes can produce a lot of different 2d contours projected on the camera sensor: sometimes you can see a distinct silhouette featuring a face and full set of paws, and sometimes it’s just a back and a curled tail. Such complex objects can be handled by a CNN very efficiently by using a simple rule: ... Read More Source June 21st, 2015 No Comments # Where does image recognition fail? Photo shows image recognition has a long way to go. Source June 20th, 2015 In Business No Comments # Sex, Google, and how sex writers adapt I hope Violet Blue writes more about this: I had to sideline valuable freelance gigs to get this move done, and it had to be done ASAP, because Google’s algo changes were (are) really hurting me. In the bad old days of print publishing, there was a lot of evil censorship, but at least it was easy to spot. There are, after all, all the famous cases against various novels: Allen Ginsburg’s “Howl”, novels like “Naked Lunch”, etc. Nowadays the forces ... Read More Source June 20th, 2015 No Comments # How NodeJs fails to deal with backpressure Interesting: The Node concurrency model is kind of like a credit card for computing work. Credit cards free you from the hassle and risks of carrying cash, and they are completely great in almost every way, unless you spend more than you make. It’s hard to even know you have spent more than you make until the next bill comes. Similarly, node lets you do more work, and it’ll call you back when it’s done, whenever that is. You might not ... Read More Source June 19th, 2015 No Comments # Git history should show you reality, not a cleaned up version of reality Well said: The obsession of git users with rewriting history has always puzzled me. I like that the feature exists, because it is very occasionally useful, but it’s one of those things you should almost never use. The whole point of history is to have a record of what happened. If you’re going around and changing it, then you no longer have a record of what happened, but a record of what you kind of wish had actually happened. How are you ... Read More Source June 15th, 2015 No Comments # The New Netflix Netflix upgrades its website. I have my doubts about the heavy use of Javascript that’s become normal over the last 5 years. I got my current MacBook Pro in 2011 and for awhile it seemed like a fast computer. Nowadays, however, if I launch Chrome, and I have 6 or 7 pages open, the computer is under stress. If I open the terminal and run “top” I see that the load varies between 1 and 3. It never goes below ... Read More Source June 10th, 2015 In Business No Comments # Krugman’s 10 years on the recession Krugman’s first essay about the end of the housing bubble came out just about 10 years ago. Nobody would pay San Diego prices without believing that prices will continue to rise. Rents rose much more slowly than prices: the Bureau of Labor Statistics index of “owners’ equivalent rent” rose only 27 percent from late 1999 to late 2004. Business Week reports that by 2004 the cost of renting a house in San Diego was only 40 percent of the cost ... Read More Source June 10th, 2015 No Comments # The new RESTful style Apparently this style is now popular with some developers: Source June 9th, 2015 No Comments # Strange problems with Rackspace cloud machine What to make of this? root@cloud-server-01:~# emacs The program ‘emacs’ can be found in the following packages: * emacs24 * emacs24-nox * e3 * emacs24-lucid * jove Try: apt-get install root@cloud-server-01:~# apt-get install emacs24 Reading package lists… Done Building dependency tree Reading state information… Done emacs24 is already the newest version. emacs24 set to manually installed. 0 upgraded, 0 newly installed, 0 to remove and 21 not upgraded. 134 not fully installed or removed. After this operation, 0 B of additional disk space will be used. Do you want to continue? [Y/n] ... Read More Source June 9th, 2015 No Comments # Avoid RejectedExecutionException in lein :( I am curious what Dave Ray wrote here in his Seesaw repo. (defn -main [& args] (when-not (first args) (println "Usage: gaidica ") (System/exit 1)) (reset! api-key (first args)) (invoke-later (-> (make-frame) add-behaviors show!)) ; Avoid RejectedExecutionException in lein :( @(promise)) Does anyone know what this about? What causes RejectedExecutionException in lein? Source June 2nd, 2015 No Comments # When to use Patch Interesting: When should we use the PATCH HTTP method? The HTTP methods PATCH can be used to update partial resources. For instance, when you only need to update one field of the resource, PUTting a complete resource representation might be cumbersome and utilizes more bandwidth Also, the PUT method is idempotent. PUTting the same data multiple times to the same resource, should not result in different resources, while POSTing to the same resource can result in the creation of multiple resources. See also RFC 5789 ... Read More Source June 2nd, 2015 No Comments # Working with monoids Interesting: Simply put, Monoids describe types containing a binary function and an identity value. When applied to the identity value and a random value x, said function leaves its argument x untouched, returning it as a result. This short description should be enough to get the conversation started. Here’s how Haskell defines a Monoid: class Monoid m where mempty :: m mappend :: m -> m -> m mconcat :: [m] -> m ... Read More Source June 2nd, 2015 No Comments # A pipeline of agents creates a fully asynchronous programming model I recall reading this code in 2010 or 2011, when I was first learning Clojure, and at the time there was a great deal about it that I did not understand, so I missed the point: (def logger (agent (list))) (defn log [msg] (send logger #(cons %2 %1) msg)) (defn create-relay [n] (letfn [(next-agent [previous _] (agent previous))] (reduce next-agent nil (range 0 n)))) (defn relay [relay msg] (letfn [(relay-msg [next-actor hop msg] ... Read More Source June 1st, 2015 No Comments # Using reducers on the bytes in a memory mapped file This could be a powerful technique, especially when speed and parallelization are important: First, we’ll have a couple of parameters: the character set for the input and a hint for the size of chunk to break the file into. (def ^:dynamic *charset* (Charset/forName "UTF-8")) (def ^:dynamic *chunk-size* (* 10 1024 1024)) With those, we’ll break the file into chunks by skipping through it and reading ahead until we get to the end of a line. Later, when we actually read the file, this ... Read More Source June 1st, 2015 No Comments # Higher order functions in Clojure support chaining Interesting: One easy-to-miss strength of this approach is that it supports chaining. In a few places in our application, we wanted to send a computation to an agent and observe the state of the computation (e.g. to show and hide a spinner). We didn’t want to have to wire observation hooks or callbacks directly into the process, so we created a contextual function (defn with-process-callbacks [fire fun & args]). with-process-callbacks returns a function which calls fun with args, but calls fire ... Read More Source June 1st, 2015 No Comments # Stuart Sierra says avoid Dynamic Scope Dynamic scope will ruin your life. In a different presentation he says that dynamic scope is okay so long as the var is really private, and marked as private. The problem with this pattern, especially in libraries, is the constraints it imposes on any code that wants to use the library. The with-resource macro severely constrains what you can do in the body: You can’t dispatch to another thread. Say goodbye to Agents, Futures, thread pools, non-blocking I/O, or any other ... Read More Source June 1st, 2015 No Comments # Mark Seemann feels that mutating state is intuitive This is a case of someone trying to be open-minded, but still being biased because of their years spent getting comfortable with a very particular form of programming that allows a very particular form of mutable state: In FP they’ve come up with this clever concept of monads to ‘work around’ the problem of mutating state. Yes, monads are very clever, but if they feel foreign in OOD it’s because they’re not required. Mutation is an inherent part of the ... Read More Source May 28th, 2015 No Comments # Simple Design Interesting: Yagni is a way to refer to the XP practice of Simple Design (from the first edition of The White Book, the second edition refers to the related notion of “incremental design”). [1] Like many elements of XP, it’s a sharp contrast to elements of the widely held principles of software engineering in the late 90s. At that time there was a big push for careful up-front planning of software development. Let’s imagine I’m working with a startup in Minas ... Read More Source May 28th, 2015 In Business No Comments # Women in tech in India My mom took several computer programming classes in the 1970s. Women earning advanced degrees in computer science peaked in the 1980s. Women focusing on tech, at the undergraduate level, also peaked in the 1980s. At the time, being a computer programmer meant getting a comfortable job at IBM or AT&T or General Motors — some big company that would offer a big salary and decent perks for a relaxed 40 hour work week. There was no brogrammer culture, no insane ... Read More Source May 28th, 2015 No Comments # Natasha Vargas-Cooper and Kelly Faircloth on romance novels Natasha Vargas-Cooper and Kelly Faircloth are talking about the use of the word “alpha” as it relates to men and as the concept is used in romance novels. : I here quote some of Faircloth’s remarks, but the whole thing is interesting. KF: So, alphadom in romance is, in my opinion, often fundamentally about taking care of the heroine and nurturing her. It’s about all that confidence and capability being focused on the heroine and working on her behalf. Now, it ... Read More Source May 27th, 2015 No Comments # Niki Tisza writes about burnout Interesting: I read a lot and I found lots of interesting articles. Reading more and more it became clear to me I was experiencing a job burnout. I got nearly all the symptoms, even I wasn’t even 30 at that time. These were my warning signs: Fatigue Frustration or decreased level of patience Stress Lack of motivation Feeling of being overwhelmed, trapped, helplessness Losing sleep Getting sick from all the sudden Going to your previously beloved workplace because you have to, not because you want to After spending a ... Read More Source May 26th, 2015 No Comments # Why Appsflyer gave up on Python and switched to Clojure Interesting: At AppsFlyer we actually started our code base in Python. Two years later this wasn’t enough to handle the growing number of users and requests. We started to encounter issues like one of the critical Python processes taking too long to digest the incoming messages, caused mainly by string manipulations and Python’s own memory management system. Even partitioning the messages amongst several processes and servers could not overcome this. This eventually killed the process and caused data loss – ... Read More Source May 26th, 2015 No Comments # We get trapped by our virtues more than our vices I like this: Qualities That Keep You in a Sick System Loyalty Patience A strong work ethic Optimism Self-sacrifice A need to be useful to others Forgiveness Farsightedness Trust Hope You don’t need to lose these qualities to get out. But if you’re stuck and trying to figure out what’s keeping you in, remember that people rarely get stuck because of their vices. They’re usually caught by their virtues. Source May 24th, 2015 No Comments # The effect of blind auditions on orchestras Interesting: But there are many different moments when I look back and think, gosh, how could I have been so optimistic? For example, Cecilia Rouse and I decided that we would study the effect of orchestras switching to blind auditions. [In a 2000 paper in the American Economic Review, Goldin and Rouse found that the practice of having musicians audition behind a screen significantly increased the proportion of women in symphony orchestras.] Many orchestras did not know they had records on ... Read More Source May 24th, 2015 In Business No Comments # Forces that drive women’s labor force participation rates Interesting: Goldin: The quiet revolution is a change in how young women perceive the courses their lives are going to take. One of the places we see this is the National Longitudinal Survey, which began in 1968 with women who were between 14 and 24 years old. One of the questions the survey asked was, “What do you think you’re going be doing when you’re 35 years old?” In 1968, young women essentially answered this question as if they were ... Read More Source May 23rd, 2015 In Business No Comments # Sick systems Interesting: Things will be better when… I get a new job. I’m mean to you now because I’m so stressed, but I’m sure that will go away when I’m not working at this awful place. The production schedule is crazy because the client is nuts. We just need to get through this cycle, then we’ll have a new client, and they’ll be much better. She has a bad temper because she just started with a new therapist. She’ll be better when she settles ... Read More Source May 23rd, 2015 No Comments # Concurrency in Ruby Celluloid is interesting: Celluloid provides a simple and natural way to build fault-tolerant concurrent programs in Ruby. With Celluloid, you can build systems out of concurrent objects just as easily as you build sequential programs out of regular objects. Recommended for any developer, including novices, Celluloid should help ease your worries about building multithreaded Ruby programs. Much of the difficulty with building concurrent programs in Ruby arises because the object-oriented mechanisms for structuring code, such as classes and inheritance, are separate ... Read More Source May 21st, 2015 No Comments # Sandi Metz tries to solve Object Oriented problems with composition Kind of sad: She says “We love dependency injection”. First she acknowledges that the “proper” Object Oriented approach leads to more code for the same behavior: but then she says the solution is to use composition, which offers all kinds of flexibility: She says it is wonderful because in the end we get “pluggable behavior”. But if it is a good idea to pull certain methods out of an object, and make them independent, in an object that can then be injected ... Read More Source May 21st, 2015 No Comments # Sandi Metz on hidden assumptions Interesting: Our code is full of hidden assumptions, things that seem like nothing, secrets that we did not name and thus cannot see. These secrets represent missing concepts and this talk shows you how to expose those concepts with code that is easy to understand, change and extend. Being explicit about hidden ideas makes your code simpler, your apps clearer and your life better. Even very small ideas matter. Everything, even nothing, is something. Source May 19th, 2015 No Comments # Predator-Prey modeling in Clojure Interesting: Introduction to Predator-Prey Systems In this edition of the blog, I’ll discuss how you can use Clojure to solve a system of nonlinear differential equations. The particular system I’ll be solving is the Predator-Prey or Lotka-Volterra Model, which you can read all about right here. The basic concept is that you are modeling a population of predators and prey (e.g. Foxes and Rabbits, which we’ll use here). How the two populations change over time can be modeled like so: dR/dt=αR−βRF dF/dt=−γF+δRF These are differential ... Read More Source May 18th, 2015 No Comments # The life of single moms Interesting: In our culture, we want mothers to be everything: good wives, strong role models, educators, friends, and empathetic listeners. We want mothers to shed their former selves in order to carry on the role of inspiring their children to be something. We want mothers to be intelligent but compassionate; generous but self-aware; at work but at home, all at once. That responsibility is difficult enough to bear when there is another warm body willing to step into a parental role ... Read More Source May 18th, 2015 No Comments # GamerGate losers continue the argument on Wikipedia Very, very pathetic, but the argument over GamerGate continues on the Wikipedia talk page. Chrisrus continues to raise legalistic objections to those editors who are trying to be reasonable: @Gamaliel: What new accounts? What does your closing and hiding of this thread have to do with new accounts editing the article? The thread had nothing to do with new accounts editing the article or not editing it. We were talking about how people respond to reader feedback on the talk ... Read More Source May 18th, 2015 No Comments # Starve yourself Interesting: It’s calorie intake that is really fueling the obesity epidemic. But it’s not just the number of calories we’re eating as how we’re getting them. The sugar calories are particularly bad. Stanford University researcher Sanjay Basu recently led an analysis of 175 countries that evaluated the amount of sugar in each nation’s food supply. As sugar availability increased by 150 calories per person per day (the equivalent of a can of cola), there was a 1.1 percent rise in the ... Read More Source May 10th, 2015 No Comments # addShutdownHook(), to stop your app in a reasonable way Interesting and important: Problem: A program may require to execute some pieces of instructions when application goes down. An application may go down because of several reasons: Because all of its threads have completed execution Because of call to System.exit() Because user hit CNTRL-C System level shutdown or User Log-Off Concept at Abstract level: Write all the instructions(java code) in a thread’s run method and call java.lang.Runtime.addShutdownHook(Thread t). This method will then register this thread with JVM’s shutdown hook. At the time of shutting down, JVM will run ... Read More Source May 10th, 2015 No Comments # “Habits” by To Love A friend of mine in Stockholm sent me this link about Swedish singer To Love, who I had never heard of, but now I’ve spent an hour watching her videos on YouTube and I like her. Source May 10th, 2015 No Comments # Test all your code in production using “feature flags” I was talking to someone at Viacom, and he told me they were doing something very clever: they use feature flags to limit who can see new features, and in fact, all new features are at first limited to the QA team. Because of this, they have no development servers — everything is tested in production. This allows the testing to be much more realistic. Feature flag libraries in Ruby and Clojure: Ruby: rollout Clojure: shoutout Source May 8th, 2015 No Comments # Can you defend your relationship? This is a cute list: No relationship comes without its obvious detractions: the counterargument against your imaginary defense. If you’re old enough to have had a relationship, you’re old enough to have had a nagging thought about it. One of my first boyfriends was great and everything—if it weren’t for the fact that he always smelled like hot dogs. Another one seemed really into me, but he was also really into “doing donuts” in his Camaro. Here are some other assorted ... Read More Source May 8th, 2015 No Comments # The public no longer thinks of GLBT celebrities as being scandalous Once upon a time, not that long ago, this would have been a big story: Miley Cyrus… revealed to the AP that “not all her past relationships were ‘straight, heterosexual’ ones.” The piece continues, “She did not elaborate.” Miley says she already spent a lot of time struggling with traditional gender expectations—and being resentful that she was a girl. “I didn’t want to be a boy,” she clarifies. “I kind of wanted to be nothing. I don’t relate to what people ... Read More Source May 8th, 2015 In Business No Comments # What smart people miss Even when you have the right theory, you can still miss the pattern of accumulating facts: And so I anticipated and predicted the actual crisis of 2008, right? Wrong. I had all the intellectual tools I needed, I even diagnosed a housing bubble, but I somehow failed to put the pieces together. Maybe I wasn’t as completely surprised as people who believed in the inherent stability of modern economies, and I caught on fast once the thing happened, but no, ... Read More Source May 6th, 2015 No Comments # Anyone can contribute to clojure-doc.org Clojure-doc.org is the place for people to contribute. This is the important bit: Contributor-friendly This material is not covered by the Clojure Contributor Agreement and is developed using pull-requests on GitHub. This is discussed in an interesting thread on the Clojure Google Group: Assertion: “There are only a handful of people in the world with authorization to edit pages on clojure.org. ” Fact: 14 Assertion: “Far more have authorization to edit the wiki pages on dev.clojure.org — hundreds, I think. A subset of those who ... Read More Source May 6th, 2015 No Comments # The changelog for the clojure.org wiki This is not linked anywhere, but it is good to know about: Source May 6th, 2015 No Comments # The contents were now a boilerplate AT&T copyright notice claiming intellectual ownership of the otherwise still empty file If the law allows a company to copyright an empty file, then the law should be changed: In a 1984 version of Unix, things started heating up, and true grew to 276 bytes. The contents were now a boilerplate AT&T copyright notice claiming intellectual ownership of the otherwise still empty file. Source May 5th, 2015 No Comments # Caribou as the ultimate Clojure web framework? Kyle Dawkins writes: Justin Smith speaks the truth about Caribou. I’m also one of the team members, and although we did lose our funding, we’re all still around and there are a number of active Caribou projects alive and well. It does have everything Justin says, and yes, it’s imperfect, but it’s also very easy to get a site up and running quickly. But you don’t lose the modularity that we all love in the Clojure world. ... Read More Source May 4th, 2015 No Comments # “My daughter came home one day crying and said, ‘Mommy, somebody told me you made a lot of money …’ “ Interesting: WITHERSPOON: My daughter came home one day crying and said, “Mommy, somebody told me you made a lot of money …” and I was like, “Why are you crying? … I worked hard for that. You should never feel embarrassed about a woman doing well in this world.” Source May 4th, 2015 No Comments # If a language does not guarantee order in a hashmap can the hashmap be referentially transparent? It’s an interesting question. Clojure says it is referentially transparent, meaning you can remove any function and replace it with its return value, with no effect on the program, but can Clojure be referentially transparent if it does not guarantee the order of its hashmaps (especially since hashmaps are also functions in Clojure)? Note that this issue is similar to ensuring that a hash function is consistent with equals in a language, i.e. if two values x and y are ... Read More Source May 3rd, 2015 No Comments # ExecutorService makes exceptions disappear in a bad way I have been bitten by this many times, mostly in Clojure libraries that use ExecutorService under the hood: What will be the result of the following snippet? executorService.submit(() -> { System.out.println(1 / 0); }); I got bitten by that too many times: it won’t print anything. No sign of java.lang.ArithmeticException: / by zero, nothing. Thread pool just swallows this exception, as if it never happened. If it was a good’ol java.lang.Thread created from scratch, UncaughtExceptionHandler could work. But with thread pools ... Read More Source May 3rd, 2015 No Comments # JVM advice: name your thread pools Tomasz Nurkiewicz offers this bit of advice, which sounds like it would also be useful in Clojure: Name pool threads I can’t emphasize this. When dumping threads of a running JVM or during debugging, default thread pool naming scheme is pool-N-thread-M, where N stands for pool sequence number (every time you create a new thread pool, global N counter is incremented) and M is a thread sequence number within a pool. For example pool-2-thread-3 means third thread in second pool ... Read More Source May 3rd, 2015 No Comments # Poland is the most Slavic nation in the world? I did not know this, but this map shows Poland as having the highest percentage of Slavic heritage: Source May 3rd, 2015 No Comments # Clojure does not need job queues, because it has Storm, Onyx, Quasar, Pulsar I find it interesting to consider the question that maybe Clojure has so many great systems for distributed processing that it does not need the classic job queue. It’s worth considering that if you don’t need something very robust (and depending on your situation), you could just use Redis + Carmine directly to pass messages around (possibly representing jobs), and have workers pull from the message queue. There is nothing else you really need for this; it’s quite straight forward. ... Read More Source May 2nd, 2015 No Comments # Aaron Bedra: web apps in Clojure have some of the worst security Aaron Bedra – clojure.web/with-security Breda says the Clojure community needs to have a talk, because of some bad things that happened recently. The rate of people getting hacked is going up. He says: “Clojure web apps are some of the worst I have seen in terms of security. We are talking about PHP-without-a-framework levels of insecurity.” “We have bricks with no mortar.” “If I missed your library, it’s because it doesn’t exist. I could not find it on the first page of Google, ... Read More Source May 1st, 2015 1 Comment # Embarrassing code I wrote under stress at a job interview (Note: this post was, in part, inspired by John Lawrence Aspden’s post about FizzBuzz.) I write terrible code when I go to a job interview. That’s mostly because, when they ask me to solve a coding question, I get nervous. I thought it might be entertaining if I wrote about one such encounter. Yesterday I went to a job interview, at a company in New York that had once built their stack (for managing online advertising) in Ruby but who are now ... Read More Source April 29th, 2015 In Business No Comments # Startups behaving after Demo Day like someone going off a strict diet Interesting: Don’t go through the motions. At Y Combinator, we sometimes see startups behaving after Demo Day like someone going off a strict diet. During YC they’re virtuous: they work hard on their product, focus on users, and avoid distractions. They’re also checking in with us regularly. But after they raise money, some founders go on a sort of bender. They rent a fancy office, hire too many people, spend too long shipping the next version, waste lots of time schmoozing ... Read More Source April 28th, 2015 No Comments # Jim Starkey says “Well, duh” This doesn’t rise to the level of “Zed Shaw rant” style of meltdown, but Jim Starkey has decided the play the role of “famous old codger who did great work once but now seems completely out of touch“: Any discussion of the CAP “theorem” revolves around the A – exactly what does availability mean? The narrow sense is that availability means that all surviving nodes in all partitions continue to process work. This reduces the CAP idea to nothing more than ... Read More Source April 28th, 2015 No Comments # Kyle Kingsbury’s Jespen series is CAP enlightenment So, again, I am late to the party. Yesterday, by accident, I discovered Kyle Kingsbury “Jespen” series. I stayed up till 4 AM reading through it. Every article is completely amazing. I wish he could do an article on every NoSQL database, but I read somewhere that each article cost him months of effort, so it is impossible to expect more from him. I recommend every single one of these articles: Source April 27th, 2015 No Comments # Redis losing 56% of writes during a partition Kyle Kingsbury (the same guy who does cool Clojure stuff like Reimann and teasers) has an epic writeup on Redis: “In this post, we demonstrate Redis losing 56% of writes during a partition.” I have trouble finding the pithy excerpt here, because it is all good. I guess I’ll just quote the opening where Kingsbury sets up the argument, and then you can read the rest for the way things fall apart: Redis offers asynchronous primary->secondary replication. A single server is ... Read More Source April 27th, 2015 No Comments # Can MongoDB keep its promises? See “Stale reads with WriteConcern Majority and ReadPreference Primary” Kyle Kingsbury starts the fight without meaning to: In this test, MongoDB returns the value “0″ for the document, even though the only possible values for the document at that time were 1, 2, 3, or 4. The value 0 was the proper state at some time close to the partition’s beginning, but successful reads just after the partition was fully established indicated that at least one of the indeterminate (:info) CaS ... Read More Source April 27th, 2015 No Comments # Parallelism versus concurrency Someone posted this on Hacker News, and it is very good. Parallelism sends equal work to every processor, concurrency is the messy chaos of sending work to whatever processor is free, or bundling up many threads on one processor. Source April 27th, 2015 No Comments # Disque is a distributed and fault tolerant message broker, so it works as middle layer among processes that want to exchange messages The people who gave us Redis announced a new project today: Disque is a distributed and fault tolerant message broker, so it works as middle layer among processes that want to exchange messages. Producers add messages that are served to consumers. Since message queues are often used in order to process delayed jobs, Disque often uses the term “job” in the API and in the documentation, however jobs are actually just messages in the form of strings, so Disque can be ... Read More Source April 26th, 2015 No Comments # A very long Java method A common rule in programming is to keep methods as small as possible, so I am surprised to see this method in a seemingly well-run project such as ZooKeeper: private void processEvent(Object event) { try { if (event instanceof WatcherSetEventPair) { ... Read More Source April 26th, 2015 No Comments # Java performance I like Tomasz Nurkiewicz’s summary of this book: JIT (just-in-time) compiler turns out to be one of the most important tools bringing performance to the JVM. First “real” chapter goes into great details of how JIT works in different modes, how to monitor and tune it. I learnt a lot already, but the best is yet to come. Obviously garbage collection is a major concern, thus Oaks devotes two full chapters to explain all popular GC algorithms. Besides pure description, expect ... Read More Source April 26th, 2015 No Comments # Your data is the API Interesting: The first time I realized that “Data as an API” was in fact a very good idea was at Kevin Lynagh’s presetation at Öredev. However, if you want something more like a struct Clojure provides something called a record. If you know Scala this is very similar to case classes. A record can be defined like this: (defrecord Person [firstName lastName]) This creates an actual normal Java class Person with two immutable fields and implements hashCode and equals. A record also ... Read More Source April 26th, 2015 No Comments # The farce known as “object oriented programming” Jayway has a nice critique of how much real-life object oriented programming departs from the beautiful theory: One thing I have realized is that in Java we use classes for many purposes. In a typical web application written in Java using something like Spring framework you will often find: Data transfer objects (DTO:s) Services (REST API, controllers, DAO:s) Rich objects (if you’re lucky!) A DTO is just a struct and contains no behavior. To minimize the boilerplate in Java I tend to implement DTO:s using ... Read More Source April 26th, 2015 No Comments # New data structures in Clojure 1.8 Apparently there are a lot of new data structures which may arrive in Clojure 1.8, thanks to Zach Tellman: So, at the end of this exercise we have more than 5000 lines of Java, and we want to add them to the core implementation of Clojure. Ideally, we won’t introduce any bugs in the process. But the same unrolling that makes the code faster makes it significantly harder to simply read the code and verify it’s “correct”. The Clojure code which ... Read More Source April 26th, 2015 No Comments # Design patterns have social value An interesting bit from Adam Petersen: Patterns have social value too. The format arose to enable collaborative construction using a shared vocabulary. In Patterns in C I write on the groundbreaking work of architect Christopher Alexander: The patterns found in Alexander’s books are simple and elegant formulations on how to solve recurring problems in different contexts. [...] His work is a praise of collaborative construction guided by a shared language – a pattern language. To Alexander, such a language is a generative, ... Read More Source April 26th, 2015 No Comments # Automat for easy finite-state-machines in Clojure Another interesting library from Zach Tellman allows for finite state machines: For a more real-world use case, consider tracking browsing behavior on an online store. We want to see when the customer visits the cart, begins to checkout, but then returns back to the cart without having completed the checkout. Seeing this indecisive behavior, we can make a special offer. Source April 26th, 2015 No Comments # Using abstract classes to hide boilerplate code I personally never do the kind of work where I need to implement abstract classes. I was asked in a job interview why I would use an abstract class, and I came up with some nonsense answer about having a default implementation for situations where my code expected a given situation 90% of the time, and edge cases only 10% of the time. But here is an interesting example in Clojure, where it interoperates with Java, using an abstract class ... Read More Source April 26th, 2015 No Comments # Zach Tellman on specialized tuples for Clojure Other than Rich Hickey, I think I learn the most from Tellman, regarding how to do things and why they work the way they do: Most data structures are designed to hold arbitrary amounts of data. When we talk about their complexity in time and space, we use big O notation, which is only concerned with performance characteristics as n grows arbitrarily large. Understanding how to cast an O(n) problem as O(log n) or even O(1) is certainly valuable, and ... Read More Source April 26th, 2015 No Comments # When to use reify in Clojure This is a nice explantation. If you have a protocol, then you can instantiate with a record, like this: (defprotocol Foo (bar [this]) (baz [this st]) (quux [this x y])) (defrecord FooRecord Foo (bar [this] (println this)) (baz [this st] (str this st)) (quux [this x y] (str this (* x y)))) But if only need to instantiate the protocol one ... Read More Source April 25th, 2015 No Comments # ExecutorCompletionService How very much easier it is to use core.async in Clojure! My one concern is that core.async has a thread pool that is set to the number of CPUs + 2, so the thread pool is small and rigid. Each call to contentFuture.get() waits until downloading given web site (remember that each Future represent one site) is finished. This works, but has a major bottleneck. Imagine you have as many threads in a pool as tasks (20 sites in that ... Read More Source April 25th, 2015 No Comments # Limit new features to a subset of your users Inspired by the Ruby gem “Rollout”, Shoutout offers user buckets on which you can test new features: Storage Unlike rollout, shoutout is completely storage agnostic. You’ll have to implement your own storage backend, which implements ShoutoutStorage. The storage protocol has two functions, read-from-storage, and write-to-storage, both of which should be simple enough to implement. Both deal purely with serialized strings, and string keys, shoutout does the serialization logic itself. The library provides an in memory store (used for testing) that you could ... Read More Source April 24th, 2015 No Comments # A Redis queue There is a reason why so many message systems are using Redis as their backend: Source April 24th, 2015 No Comments # Redis: I am late to the party The strangest thing about the human mind is the degree to which context shades our memories. So now that I’m using Redis I realize that I’ve been reading about it for years without realizing how diverse its uses are. I just now decided to re-read the Github post from 2009 “Introducing Rescue” and I only now realize that it mentions both Redis and Kestrel, 2 things I had not heard of then, mere names that I read and forgot because ... Read More Source April 22nd, 2015 No Comments # Design patterns are failures I love this: Design Patterns was especially well-timed because it offered a ray of hope for people who were mired in the Woes of the New OO Programmer. You see, the OO camp was saying: “EVERYTHING IS AN OBJECT! YOU WILL THINK OF EVERYTHING AS OBJECTS FROM NOW ON! THE OO PROGRAMMING PARADIGM IS: CREATE YOUR CLASSES, ADD OPERATIONS TO THEM, AND LAUNCH THE DAMN THING!” The last sentence (forgive the caps, sorry) is a pretty reasonable paraphrase of Stroustroup in his ... Read More Source April 22nd, 2015 No Comments # Singletons are evil This is great: Everyone Loves Singleton Why is the Singleton so attractive? I’ll be the first to admit: I liked it too. No, scratch that – I loved the Singleton. It felt like an old friend from the moment I laid eyes on it. It was simple and beautiful. I’ll tell you why: it’s because the Singleton pattern is a throwback to non-OO programming. It’s a lifeline for people who didn’t understand a single word that the Gang of Four were trying ... Read More Source April 21st, 2015 No Comments # What happened to Ani DiFranco? What happened to Ani DiFranco? In 1993 I dated a woman who introduced me to Ani DiFranco. For the next 12 years, a lot of my female friends were in love with Ani DiFranco. She was a huge icon to a particular demographic. danah boyd maintained a page of Ani DiFranco lyrics. (I also liked DiFranco very much.) Over the last 10 years, DiFranco has vanished. I am not aware of any of my female friends who still follow her. ... Read More Source April 20th, 2015 No Comments # Steve Yegge’s contribution to the revolt against Object Oriented Programming Somehow I waited till today to read Steve Yegge’s 2006 rant “Execution in the Kingdom of Nouns”. I’ve seen it recommended many times, but I only now read it. I wish I had read it in 2006. I am not sure I would have understood it, but in retrospect it clearly marks the end of the mania that for Object Oriented Programming that Paul Graham had noted in 2001 (Paul Graham wrote: “There is a kind of mania for object-oriented ... Read More Source April 20th, 2015 No Comments # Encapsulation of information is folly This is strongly stated, and surprising: Datatypes and protocols are opinionated While datatypes and protocols have well-defined relationships with host constructs, and make for a great way to expose Clojure functionality to Java programs, they are not primarily interop constructs. That is, they make no effort to completely mimic or adapt to all of the OO mechanisms of the host. In particular, they reflect the following opinions: Concrete derivation is bad: you cannot derive datatypes from concrete classes, only interfaces You should always program to ... Read More Source April 20th, 2015 No Comments # Why have both deftype and defrecord? This is good: It ends up that classes in most OO programs fall into two distinct categories: those classes that are artifacts of the implementation/programming domain, e.g. String or collection classes, or Clojure’s reference types; and classes that represent application domain information, e.g. Employee, PurchaseOrder etc. It has always been an unfortunate characteristic of using classes for application domain information that it resulted in information being hidden behind class-specific micro-languages, e.g. even the seemingly harmless employee.getName() is a custom interface to ... Read More Source April 12th, 2015 No Comments # Evening, by Susan Minot (The 1st of 20 reviews of romance novels. I’m reading romance novels so I can learn how to better write about romance in my own works of fiction.) In the early 1990s Susan Minot published some articles in Esquire magazine and I liked her stuff so I’ve been meaning to read some of her books. I was busy for the last 25 years, but I just finally got to reading her novel Evening. Her focus is with the white upper-middle class ... Read More Source April 11th, 2015 In Business No Comments # China became powerful for all the wrong reasons Interesting: Suppose you’re in a setting where the rule of law and contract enforcement are really weak. And you realize that they don’t change overnight. Are you better off promoting the set of policies that presume that rule of law and contract enforcement will take care of themselves, or are you better off recommending a strategy that optimizes against the background of a weak rule of law? And I say that the evidence is that you do ... Read More Source April 11th, 2015 In Business No Comments # Print journalism is dying and there is no way to save it Clay Shirky is always interesting: A year or so ago, I was a guest lecturer in NYU’s Intro to Journalism class, 200 or so sophomores interested in adding journalism as a second major. (We don’t allow students to major in journalism alone, for the obvious reason.) One of the students had been dispatched to interview me in front of the class, and two or three questions in, she asked “So how do we save print?” I was speechless for a moment, then ... Read More Source April 10th, 2015 No Comments # Zed Shaw’s legacy I love this: Once again, Zed Shaw preaches the truth. The worst thing about the era of the Internet is how often I (and I think all of us) read something that effects my thinking forever, and then that thing vanishes, and no one can ever read it, and no one can ever hope to understand what shaped my thinking on a particular subject. 100 years ago, if I read a good book, there was a good chance some copy of ... Read More Source April 7th, 2015 No Comments # Ruby closures borderline macro syntax A good reminder of how much block syntax gives you: if user.save # publish event 'user.created', with payload {user: user} Publisher.broadcast_event('user.created', user: user) end def create_user(params) user = User.new(params) # publish event 'user.created', with payload {user: user}, using block syntax # now the event will ... Read More Source April 6th, 2015 No Comments # If the only thing you care about is behavior then ruby suggests to implement it as a module Interesting: Lets look at this ruby code. class Util def self.double(i) i*2 end end Util.double(4) #=> 8 Here we have a Util class. But notice that all the methods on this class are class methods. This class does not have any instance variables. Usually a class is used to carry both data and behavior and ,in this case, the Util class has only behavior and no data. Similar utility tools in ruby Now to get some perspective on this discussion lets look ... Read More Source April 6th, 2015 No Comments # Ruby On Rails as the frontend for polyglot programming True: Rails is a good framework for proof-of-concept and small applications, it promotes conventions over configuration. As the application grows it becomes difficult to maintain. This is primarily because rails promotes coupeled architecture with fat model, skinny controller approach. Developers need to adopt to new patterns and create new conventions to keep projects moving on pace and in shape. PUBSUB can help us resolve some of the problems we face often. And the subscribers can be written in any language, allowing for ... Read More Source April 6th, 2015 In Business No Comments # The evil of granting companies property rights to IP numbers Awful: EthanHeilman I wrote a blog entry about some of these issues. http://ethanheilman.tumblr.com/post/104839763080/are-ip-address-allocations-property IANA specifically states that a free-market of IP addresses would be harmful, instead they argue that IP allocation should be based on need and not treated as property. >ISPs are required to utilize address space in an efficient manner. To this end, ISPs should have documented justification available for each assignment. The regional registry may, at any time, ask for this information. If the information is not available, future allocations may ... Read More Source April 6th, 2015 No Comments # What Ruby sees when you monkeypatch Interesting: That is, the code: module Foo puts Foo.object_id end is functionally equivalent to: # Create a new Module instance and assign it to the Foo constant Foo = Module.new # Reopen the Module instance assigned to the constant Foo for modification module Foo # Do stuff in here to add functionality to the Foo module # Since Foo is already defined, we can get its object_id. puts Foo.object_id end This certainly doesn’t make sense coming from a compiled language standpoint (after ... Read More Source April 6th, 2015 No Comments # Shocking fact: using Spring used to mean giving up all compile time checks in Java I have been reading Java Programming Interviews Exposed. I never understood these “job interview” books before. Who can get ready for a job interview by reading a book? Surely that’s just cheap marketing by the publishers, who prey on developers insecurities? However, I’ve decided I like this book. Not for job interviews — it sucks for that. But as a broad overview of the Java eco-system, it is perfect. It’s got a little about serialization, a little about dependency injection, a ... Read More Source April 5th, 2015 No Comments # Why does Google point to 5 year old articles about Railties? Sometimes Google disappoints. If you search for “gem plugins railtie” the first link is to an article that is 5 years old. Is there truly no better information? That article says: Railtie plugins are easy to turn into gem plugins for Rails. This makes them easy to distribute, manage, and upgrade. The first thing you need is a gem. If you don’t have a gem yet, you can create a new gem easily using Bundler. Just run bundle gem my_new_gem ... Read More Source April 5th, 2015 No Comments # Why (right side) cast a variable in Java Interesting: The question: Is there some general rule about when a variable needs to be cast (on the right side)? Why is it that HttpURLConnection is cast on the right side here: final HttpURLConnection connection = (HttpURLConnection) url.openConnection(); but responseInputStream does not need to be cast on the right side here: final InputStream responseInputStream = connection.getInputStream(); How does a Java programmer know when to do this kind of casting, and when not to? The answer: In this program, you cast ... Read More Source April 3rd, 2015 No Comments # ActionDispatch and middleware Interesting: When you start using ruby on rails, its ease of use makes it great to get you started. Everything works out of the box. You may be using Devise for authentication, Cancan for authorization and every time you need something that you believe Rails do not provide, you search google for a gem doing what you seek. And joy is everywhere, your app works fine, you didn’t even need to write that much code to get where you are! It’s awesome. Until ... Read More Source April 2nd, 2015 No Comments # ActiveJob offers a uniform queue interface for Rails I love that Rails 4.2 offers a unified interface for working with queues. This is obviously important for Ruby, since Ruby sucks at concurrency, and needs to rely on a lot of queue technology to facilitate most forms of async (some people then jump in: “blah, blah, blah, Fiber, etc, etc.” I get that, but still, the reality is, using Fiber does not magically give you Clojure, or Elixir). Why do I need Background Jobs? One common situation for needing background ... Read More Source March 31st, 2015 No Comments # The folklore that allows technology to work They make this sound negative, but every branch of engineering is built up on folklore, some of which stretches back for thousands of years. On a practical level, few us ever need to go back to first principles. It is faster and more efficient to work from rough rules of thumb that work most of the time. In practice, very few people study the primary sources (or even authoritative secondary sources) when they’re programming and then work forward from first ... Read More Source March 31st, 2015 No Comments # Why is Clojure leaner than Object Oriented Programming? Interesting: The person opposite will be wondering why is Clojure so lean and effective? You may think it’s unsporting and a bit negative to shoot fish in a barrel, but here I like to attack OO a bit. You can’t avoid this anyway as OO is the elephant in the room being the mainstream status quo. I’ve have found however that this can be a light and fun conversation, as people generally enjoy trading war stories and rallying against established orthodoxy. We ... Read More Source March 31st, 2015 No Comments # Types of functions: where Functional Programming meets Object Oriented Programming Interesting: Over the past year I have used Prismatic Schema extensively on a large Clojure project. We really like the aid that if offers in understanding, debugging, and using our code. However, we regularly feel a bit of a let down when an argument to a function is another function. Prismatic Schema doesn’t allow you to say much in these cases beyond: this arg is a function. To address this we extended Prismatic Schema to allow us to add type annotations ... Read More Source March 31st, 2015 No Comments # Jodhaa Akbar I recently watched the movie Jodhaa Akbar. Watching it I realized how strange it was that Richard Attenborough’s version of Ghandi was so entirely secular. Jodhaa Akbar shows Akbar experiencing the mystical wonders of Allah and Jodhaa experiencing the mystical wonders of Krishna. But Gandhi is not shown experiencing any mystical wonders, even though he was a great spiritual leader. Attenborough’s version of Gandhi is very Western and secular. Source March 30th, 2015 No Comments # Mistake: At least make your fancy app act like a web page A lot of people now say stupid things like this: To add insult to injury, web development has become more and more dominated by rich client side work over the last 5 years. Javascript used to be a tool that you used as sparingly as possible, sprinkling in just the barest hint of dynamic behavior where it was absolutely necessary. Now it’s common to start a new project and assume that 50% or more of the code will be Javascript. At ... Read More Source March 23rd, 2015 No Comments # The most important election in the history of Israel Interesting: I’m not interested in debating the normative side of the election, or various peace plans, right now. What I find striking is how unready many critics are to confront what has happened, not just in the “Plan B” sense but also rhetorically. The possibility that civil rights progress, peace progress, and self-governance and democratic progress simply have stopped, and won’t be back any time soon, is before us. If anything, matters might become worse yet, especially once ... Read More Source March 23rd, 2015 No Comments # Does not globally pollute Array, Hash, Object or AR::Base. Kaminari is Clean. That is listed as its top feature. What does “clean” mean? “Does not globally pollute Array, Hash, Object or AR::Base.” Sure this is an argument against Object Oriented Programming? Doesn’t this make plain data structures seem wonderful? Oh but wait, it fails the “clean” test in one big way: Modern The pagination helper outputs the HTML5 tag by default. Plus, the helper supports Rails 3 unobtrusive Ajax. Embededed HTML! Fun times! Let’s party like its 1999! Source March 23rd, 2015 No Comments # ActiveRecord scopes I knew this once, but forgot during the time I have not worked with Rails: scope(name, body, &block) Link Adds a class method for retrieving and querying objects. A scope represents a narrowing of a database query, such as where(color: :red).select(‘shirts.*’).includes(:washing_instructions). class Shirt < ActiveRecord::Base scope :red, -> { where(color: ‘red’) } scope :dry_clean_only, -> { joins(:washing_instructions).where(‘washing_instructions.dry_clean_only = ?’, true) } end The above calls to scope define class methods Shirt.red and Shirt.dry_clean_only. Shirt.red, in effect, represents the query Shirt.where(color: ‘red’). You should ... Read More Source March 23rd, 2015 No Comments # Constraints on routes in Rails I did not know this: 4.2 Specifying Constraints You can use the :constraints option to specify a required format on the implicit id. For example: resources :photos, constraints: { id: /[A-Z][A-Z][0-9]+/ } This declaration constrains the :id parameter to match the supplied regular expression. So, in this case, the router would no longer match /photos/1 to this route. Instead, /photos/RR27 would match. You can specify a single constraint to apply to a number of routes by using the block form: constraints(id: /[A-Z][A-Z][0-9]+/) do resources ... Read More Source March 23rd, 2015 No Comments # You can’t take my pretty adjectives, damn you In Strunk and White’s book Elements Of Style we are told that adjectives are bad. But here’s a book that says they are all liars: http://languagelog.ldc.upenn.edu/nll/?p=18345 They also say that we should not start sentences with “but”. But I look them straight in the eye and say “Make me.” Source March 22nd, 2015 No Comments # I hate dependencies As an example, I’ll talk about Nokogiri. For years now, every time I have to setup up a Rails project on a new machine, I struggle with the installation of Nokogiri. I usually only do this once or twice a year, which is just enough time for me to forget the details, so I have to go through all the pain again. Error installing nokogiri Failed to build gem native extension. mkmf.rb can’t find header files ... Read More Source March 18th, 2015 No Comments # Ruby mixins are powerful A reminder of Ruby’s mixins powers: I loosely modeled the BigInteger and Number classes after the Java versions. The BigInteger class defines one constructor and directly inherits one method from the Number base class. To mix in the methods implemented in the Stringify and Math modules with the BigInteger class you will note the usage of the include and extend methods, respectively. # Create a new object bigint1 = BigInteger.new(10) # Call a method inherited from the base class puts bigint1.intValue # ... Read More Source March 16th, 2015 No Comments # The cost of failure I was sick from 1994 to 2000, so I can relate to this: Back when I made comics, I lived in a forest. I was poor. I had few options in life. I avoided the topic of college because I didn’t know what I wanted to “do with the rest of my life,” and I didn’t have the money to pay for it. It was much easier to tell myself I wanted to “do what I love, make comics for ... Read More Source March 16th, 2015 No Comments # When strongly stated opinions bring out defensive anger in computer programmers This reminds me of the reactions I got when I wrote my essay “Object Oriented Programming is an expensive disaster which must end”. Then he started by banging on everything that didn’t conform to His Way of Doing Things: his process, his tools. Everything else was “stupid,” “dumb,” “moronic.” I got the impression he was hiding his own fear of inadequacy behind a wall of disapproval and smack talk. I know this method. I used to use it myself, when I ... Read More Source March 16th, 2015 No Comments # PHP is adding types without breaking backwards compatibility This remark is very true: If I were a Python developer (of the language itself), I would be paying very close attention to how PHP has handled deprecation and breaking changes. and: There’s been an effort with PHP 7 to try and avoid a Python 2/3-style situation. The PHP 5 to 7 jump should be much smaller than from 4 to 5. and this about PHP: I think of it as the English language of programming. Picking and choosing all of the best ... Read More Source March 16th, 2015 No Comments # CSS media rules for iPads and iPhones Interesting rules for screening for iPads and iPhones: /* default styles here for older browsers. I tend to go for a 600px – 960px width max but using percentages */ @media only screen and (min-width:960px){ /* styles for browsers larger than 960px; */ } @media only screen and (min-width:1440px){ ... Read More Source March 16th, 2015 No Comments # What Rails asset pipeline looks like It’s interesting to actually look at the paths being managed. Rails.application.config.assets.paths => [ "/Users/lkrubner/projects/pasha/magstore/app/assets/images", "/Users/lkrubner/projects/pasha/magstore/app/assets/javascripts", "/Users/lkrubner/projects/pasha/magstore/app/assets/stylesheets", "/Users/lkrubner/projects/pasha/magstore/vendor/assets/javascripts", "/Users/lkrubner/projects/pasha/magstore/vendor/assets/stylesheets", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/bundler/gems/refinerycms_membership-cd49cac06a43/app/assets/images", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/bundler/gems/refinerycms_membership-cd49cac06a43/app/assets/javascripts", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/bundler/gems/refinerycms_membership-cd49cac06a43/app/assets/stylesheets", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/bundler/gems/refinerycms_membership-cd49cac06a43/vendor/assets/javascripts", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/gems/refinerycms-wymeditor-1.0.6/app/assets/images", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/gems/refinerycms-wymeditor-1.0.6/app/assets/javascripts", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/gems/refinerycms-wymeditor-1.0.6/app/assets/stylesheets", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/gems/jquery-ui-rails-5.0.3/app/assets/images", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/gems/jquery-ui-rails-5.0.3/app/assets/javascripts", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/gems/jquery-ui-rails-5.0.3/app/assets/stylesheets", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/bundler/gems/refinerycms-11f8d1eeb45e/core/app/assets/images", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/bundler/gems/refinerycms-11f8d1eeb45e/core/app/assets/javascripts", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/bundler/gems/refinerycms-11f8d1eeb45e/core/app/assets/stylesheets", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/bundler/gems/refinerycms-11f8d1eeb45e/core/vendor/assets/javascripts", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/gems/refinerycms-i18n-3.0.0/app/assets/images", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/gems/turbolinks-2.5.3/lib/assets/javascripts", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/gems/jquery-rails-3.1.2/vendor/assets/javascripts", "/Users/lkrubner/projects/pasha/magstore/vendor/bundle/ruby/2.1.0/gems/coffee-rails-4.0.1/lib/assets/javascripts" ] Source March 16th, 2015 No Comments # Functional design patterns Interesting: A good talk (~45 min) on this topic by Stuart Sierra: http://www.infoq.com/presentations/Clojure-Design-Patterns Not necessarily binding and authoritative, but I recognized a number of his examples from my own experience using FP for data analysis. Examples written in Clojure, but likely applicable to any FP language. The names he gives to the patterns he covers are: State/Event Consequences Accumulator Reduce/Combine Recursive Expansion Pipeline ... Read More Source March 16th, 2015 No Comments # The tech industry reaction against cloud computing Interesting: When Matt and Quin founded Swiftype in 2012, they chose to build the company’s infrastructure using Amazon Web Services. The cloud seemed like the best fit because it was easy to add new servers without managing hardware and there were no upfront costs. Unfortunately, while some of the services (like Route53 and S3) ended up being really useful and incredibly stable for us, the decision to use EC2 created several major problems that plagued the team during our first year. Swiftype’s ... Read More Source March 16th, 2015 No Comments # Now when confirmation validations fail, the error will be attached to :#{attribute}_confirmation instead of attribute. Upgrading to Rails 4. I am not sure what this means, so I will leave this note to myself, and come back and read more later. 5.6 Active Model Rails 4.0 has changed how errors attach with the ActiveModel::Validations::ConfirmationValidator. Now when confirmation validations fail, the error will be attached to :#{attribute}_confirmation instead of attribute. Rails 4.0 has changed ActiveModel::Serializers::JSON.include_root_in_json default value to false. Now, Active Model Serializers and Active Record objects have the same ... Read More Source March 16th, 2015 No Comments # Rails adds a lot to the$LOAD_PATH

I guess I knew this but I was still surprised to look and see how many paths there are in one small Rails project.

bundle exec rails c

March 6th, 2015

# The company transition from one big group to many groups

Interesting:

Everyone doesn’t know what’s going on anymore.

When you all fit around a single table (or a single Google Hangout) it’s easy for everyone to feel like they know what’s going on. Most people were probably wearing multiple hats and in constant communication as you focused on a single, core thing your business tries to do well.

But now things, have changed. Not only do people wear fewer hats, you probably even have multiple people to do many of the jobs.

Gone are ...

March 6th, 2015

# Job interviews for computer programmers are full of bias

Interesting:

Confidence bias selects for candidates who are good at interviewing.

There are people who have the social skills to actively listen to someone else’s technical points, to guide a discussion with questions of their own, or to spot opportunities to redirect a tough question back to familiar territory. Those people build impressive resumes. They effortlessly pass “culture fit” tests. And a lot of them can’t code.

Confidence bias excludes candidates who don’t interview well.

For every genuinely competent and effective developer who ...

March 6th, 2015

# Customization killed MySpace

From GeoCities to MySpace to Facebook the trend has been to less customization. Perhaps this is specialization: if you want a website, then go get a website, but if you want social, then let’s stick with a standard UI so that folks can focus on the social bits.

Could they have avoided losing out to Facebook? I think if they created MySpace 2.0 without all the crap (essentially what Facebook did) and made it easy to migrate your accounts and ...

March 6th, 2015

# The end of the globalization consensus

After 1945, the USA lead the effort to establish a liberal zone of less restricted trade, an effort to step away from the protectionism of 1914-1945. And for awhile the leadership of the USA was unified on the need for this effort. But consensus is dying:

Summers’s ascendance is a reflection of the abandonment by much of the party establishment of neo-liberal thinking, premised on the belief that unregulated markets and global trade would produce growth beneficial to worker and C.E.O. ...

March 6th, 2015

# Women stealing happiness from women

Interesting:

“You know Weil hired Lauren? She just got her letter yesterday.”

It was Emma, smiling at me as though there was no one else she’d rather see.

“I guess they’re less fixated on first-year grades than they pretend,” she said, “because Lauren’s first year grades were”–here she made a soft clicking noise that made me want to strangle her.

“Incoming,” hissed Emma’s best friend, another girl who was notable mostly because her parents owned one of New York’s most expensive restaurants. And ...

March 6th, 2015

# The professionalization of childhood sports is child abuse

Interesting:

“It’s definitely child abuse,” Dohrmann said in an interview with ThinkProgress.

Dohrmann said that LeBron James Jr. might be an example of a rare kid with the support system that will allow him to survive the maw of youth basketball. He has a father who understands the system, is used to the attention and doesn’t need the money. He’s likely to get a coach who understands the game and even if he doesn’t he has his dad, one of the greatest ...

March 6th, 2015

# The countryside is out of fashion

The reasons why the college failed:

Sweet Briar officials cited overarching challenges that the college has been unable to handle: the lack of interest from female high school students in attending a women’s college like Sweet Briar, declining interest in liberal arts colleges generally and declining interest in attending colleges in rural areas. Sweet Briar is in the foothills of the Blue Ridge Mountains in Virginia. “We are 30 minutes from a Starbucks,” said James F. Jones Jr., president of ...

March 3rd, 2015

# What is the right way to use micro-services?

Interesting:

What I find over and over again is that micro-services appeal to leadership more than the developers. This is a somewhat confusing revelation considering micro-services are considered an architectural approach, and project managers are not supposed to fall in love with an architecture (at best, they are weary of it because ‘architecture’ is typically a code word for more boxes and increased cost and time to delivery). And yet.

…Beyond solving the sheer size problem, micro-services promise to solve the ‘different ...

March 3rd, 2015

# I don’t get the zombie craze

All the zombie movies — I am not clear why this genre is so popular now. Typically when Sci-Fi has some popular breakthrough its because of events happening elsewhere in society. Invasion of the Body Snatchers was a hit when Anti-Communist hysteria was at its peak. Star Trek was a hit when the USA government was actually trying to get to the moon. Planet Of The Apes was a hit when white America no longer felt free to speak openly ...

March 3rd, 2015

# If mid-level managers are useless, then why do they exist?

At this point I think I can reasonably say that I’ve read thousands of stories about the stupid incompetence of mid-level managers. And I’m beginning to wonder if this genre of story is teaching us an important truth. I used to think the answer was “yes” but now I’m wondering, why do companies continue to have mid-level managers, given the endless number of these stories that have been brought up, at least since the 1960s, if not earlier?

A company ...

March 3rd, 2015

# Europe has seen a surge in voluntary childlessness

Interesting:

Europe has also seen a surge in “child-free” adults—voluntary childlessness. The proportion of childless 40-something women is one in five for Sweden and Switzerland, and one in four for Italy. In Berlin and in the German city-state of Hamburg, it’s nearly one in three, and rising swiftly. Europe’s most rapidly growing family type is the one-person household: the home not only child-free, but partner- and relative-free as well. In Western Europe, nearly one home in three (32%) is already a ...

March 2nd, 2015

# Men ask Sarah Lacy to think of the children

This is awesome:

One of the highest profile positive symbols of the new generation of empowered women is Lena Dunham. I am avowedly not a fan of the TV show “Girls,” which I thought meant I wasn’t a fan of its creator. But my respect for Dunham just keeps growing with every interview with her I’ve read.

Last month, in the airport on the way to Nashville, I picked up a copy of Elle magazine which had Dunham on the cover. It ...

March 1st, 2015

# The problem with the ActiveRecord, as a pattern

Interesting:

The pattern (or one might say the way it is implemented) has several issues:

It (seriously) violates SRP. In a typical implementation of the pattern you will have the following set of methods and properties in every class: Getting the data from database. Instantiating a new instance in memory for inserting it into the database. Saving changes to the database. Loading related entities. Validation. Usually loads of methods (inherited from the base framework class) to deal with all the complexity involved with the above-mentioned methods. Column related ...