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# Effective Shell Part 1: Navigating the Command Line

## 12 days ago | Dave Kerr: dwmkerr.com

Text in the command line can quickly get unwieldy. Here are some simple tricks you can use to navigate in the command line.

# Promises, Async and Await in Node.js

## 23 days ago | Rocky Jaiswal: Still Learning

This week we had the much awaited Node.js 8.0.0 release! Node is getting faster and better all the time. This release also makes the async / await feature available natively. But before we look at async / await let us quickl ...

# A utility to help you wait for ports to open

## 29 days ago | Dave Kerr: dwmkerr.com

There are occasions where you might need to have scripts or commands which wait for TCP/IP ports to open before you continue. I've come across this need again and again when working with microservices, to make my life easier I've created a little utility called wait-port which will wait

# Engineering Leader: How to make a difference?

## about 1 month ago | Subodh Gupta: Subodh's Blog

Being an engineering leader is not an easy task, especially when you are stepping into this role as a first-timer. Seldom you go through a training, however in most situations you are expected to figure it out yourself with little or no guidance. Often leadership demands you to play following roles: People ManagerProduct/Business knowledgeArchitect/Senior DeveloperVision for technologyI will be writing separate blogs to cover the first two roles. For a beginner, last two roles are very important to gain credibility of the team which is the most important factor in succeeding at your job. As a technical leader, you will be facing the challenges from all the directions like decision making, improving team efficiency and choosing the technology roadmap for your team. However, I hope adopting following patterns can help you sail through these challenges. Decision Making: When hit with the problem, as a techie you rely on your technical skills and often start suggesting solutions immediately which is fine in few situations, however in my experience better way would be to ask pointed questions to lead your team in driving the right decision. Questions should be repeatedly asked to highlight the blemishes in the suggested design. For example, "How would you take care of security?", "How are you addressing scalability?", "How would application behave under these circumstances?" and many more. It's easier to jump to the solution by picking up the first suggestion by trusting the loudest (not literally) person in the room. However, as a coach, you should be involving everyone in the decision-making process. Find out what is missing in the room, is it the knowledge, the skill or the participation. You need to create enough opportunities for everyone to participate. To do that you need to think about various factors like structure of the team, personalities in the team etc. These factors can be neutralized to an extent by bringing everyone to a common understanding of the problem. In my experience, following preparation before hosting an important meeting would make it easier: Share a document explaining the problem which can educate the team before the discussionDuring the meeting, explain the problem in detail so that team can align their understandingDo your homework before going to the meeting. This will help you in asking the right questions and guiding the meeting towards the solution. Improving Efficiency: Team delivers to the full potential if they are not disturbed and allowed to focus on the problem. As a leader, think about how the team is getting distracted, how can you make them focus on stories or task in hand? Improve the development processes so that you can minimize the impact on the team. For example, in a production issue churn out the non-technical part and direct developer towards solving the technical problem. Vision for Technology: Successful teams stay ahead of the technology curve. As a coach, you need to ensure that your team is adapting to changing landscape of the technology world. While working with your team to strengthen the technology muscle, you need to start focusing on what should be the future technology platform for your team. If you are not thinking at least 3-months down the line, you will lose the war while you were busy fighting battles. Be sensitive to what role you are playing in your team. You are not a developer anymore, you are a coach and coaching means understanding before suggesting, listening before speaking, advising rather than commenting. As a beginner, starting in the world of unknown unknowns of management, I hope my secret sauce can help you prepare the right dish for your team!!!

# Techniques for Efficiently Learning Programming Languages

## 2 months ago | Daniel Higginbotham: Flying Machine Studios

Learning programming languages is a skill: do it well and you'll experience one dopamine hit after another as you master something new; do it poorly and you'll feel constantly frustrated and even give up. What follows are the best techniques for learning programming languages that I've picked up over years of teaching programming by writing books and articles, doing talks, and running a training course. Many of these techniques are pulled from books explaining the latest research in efficient learning, and you can find those books (along with other great programming books) at Community Picks: Learn Programming. Test Yourself Constantly to Defeat The Illusion of Competence One of the worst ways to learn is to re-read or re-watch material. This kind of review gives you the feeling that you understand the topic covered because it seems like you're understanding the topic effortlessly. Researchers call this the illusion of competence. A significantly better approach (and one of the best techniques you can employ) is to test yourself constantly. Instead of re-reading what a function or class or object is, ask yourself to define these concepts or use them in a short program; force yourself to somehow demonstrate your understanding. This process often feels uncomfortable, but it's much more efficient at forming long term memories. You can take this one step further and test yourself before you've covered the material by, for example, attempting exercises before reading a chapter. Remarkably, this has also been shown aid memory formation. The impressive impact that testing has on learning is called the testing effect, and here are some specific ways you can take advantage of it: Before reading a chapter or watching a video, try guessing at what you're about to learn and write it down. Try doing a chapter's exercises before reading the chapter. Always do exercises, even the hard ones. It's OK to give up on an exercise and come back to it later (or never, even), but at least try it. (More on this in the next section.) Read a short program and try to recreate it without looking at the original code. Or, go smaller and do this with a function. Immediately after learning a new concept like objects, classes, methods, or higher-order functions, write code that demonstrates that concept. Create diagrams that illustrate concepts, both in isolation and how they relate to each other. Blog about a concept you just learned. Try explaining the concept to a non-technical friend. (I did this a lot when writing Clojure for the Brave and True; being able to explain an idea in layman's terms forces you to understand the idea deeply.) Many of these techniques boil down to write some code! With programming it's easy to believe we're learning a lot just by reading because programming is text-heavy and conceptual. But it's also a skill, and like any other skill you have to perform it to get better. Writing code is the best way to reveal your incorrect assumptions about programming. The faster you do that, the faster you can make corrections and improve. If you'd like to learn more about the testing effect, check out make it stick: The Science of Successful Learning. Take Time to Unfocus If you're stuck on a problem or don't understand something you just read, try taking a walk or even a shower -- anything to enter a relaxed, unfocused state of mind. It probably seems counterintuitive that one of the best ways to get unstuck is to stop trying for a little while, but it's true. The problem is that it's easy for us to put on mental blinders when we're focusing hard on a problem. I mean, that's pretty much what "focus" means. But by focusing hard, we're exploring only a small portion of the solution space. By unfocusing, our unconscious mind is able to explore and make connections across vast swaths of our experience. To me it's like when you're trying to find a destination on a paper map (remember those?). You can unconsciously become convinced that the city you're trying to reach should be right here! in the upper-left qudrant of the map, so you look at it over and over without success. Then you put the map down and take a deep breath and stare at nothing for a minute, and when you look at the map again the actual location jumps out at you immediately. We've all had the experience of having a sudden insight in the shower; now you have a slightly better understanding of why that happens, and you can employ the technique on purpose. Personally, I will actually take a shower if I'm stuck on something, and it's remarkable how well the technique works. And how clean I am. If you'd like to learn more about the focused and diffuse modes of thinking, check out A Mind for Numbers: How to Excel at Math and Science (Even If You FLunked Algebra). Don't Waste Time Being Frustrated Related to the last section: don't waste time being frustrated with code. Frustration leads us into doing stupid things like re-compiling a program or refreshing the browser with the hope that this time it will be magically different. Use frustration as a signal that there's a gap in your knowledge. Once you realize you're frustrated, it can help to take a step back and clearly identify the problem. If you've written some code that's not working, explicitly explain to yourself or someone else the result that you expected. Use the scientific method and develop a hypothesis for what's causing the unexpected behavior. Then test your hypothesis. Try again, and if a solution still eludes you, put the problem aside and come back to it later. I can't tell you how many times I've thrown my laptop in disgust over a seemingly unsolvable problem, only to look at it the next day and have an obvious solution pop into my head immediately. This happened last week, even. Identify Which Programming Language Aspect You're Dealing With Personally, I find it useful to keep in mind that when you're learning a programming language, you're actually learning four things: How to write code: syntax, semantics, and resource management The language's paradigm: object-oriented, functional, logic, etc. The artifact ecosystem: how to build and run executables and how to use libraries Tooling: editors, compilers, debuggers, linters It's easy to get these four facets mixed up, with the unfortunate result that when you run into a problem you end up looking in completely the wrong place. Someone who's completely new to programming, for example, might start out by trying to build iOS apps. They might try to get their app running on a friend's phone, only to see some message about needing a developer certificate or whatever. This is part of the artifact ecosystem, but an inexperienced person might see this as a problem with how to write code. They might look at every line they wrote to figure out the problem, when the problem isn't with their code at all. I find it easier to learn a language if I tackle each of these aspects systematically, and in another blog post I'll present a general list of questions that need answering that should help you in learning any language. Identify the Purpose, External Model, and Internal Model Whenever you’re learning to use a new tool, its useful to identify its purpose, external model and internal model. When you understand a tool's purpose, your brain gets loaded with helpful contextual details that make it easier for you to assimilate new knowledge. It's like working on a puzzle: when you're able to look at a picture of the completed puzzle, it's a lot easier to fit the pieces together. This applies to languages themselves, and language libraries. A tool's external model is the interface it presents and the way it wants you to think about problem solving. Clojure’s external model is a Lisp that wants you to think about programming as mostly data-centric, immutable transformations. Ansible wants you to think of server provisioning in terms of defining the end state, rather than defining the steps you should take to get to that state. A tool's internal model is how it transforms the inputs to its interface into some lower-level abstraction. Clojure transforms Lisp into JVM bytecode. Ansible transforms task definitions into shell commands. In an ideal world, you wouldn’t have to understand the internal model, but in reality it’s almost always helpful to understand a tool's internal model because it gives you a unified perspective on what might seem like confusing or contradictory parts. When the double-helix model of DNA was discovered, for example, it helped scientists make sense of higher-level phenonema. My point, of course, is that this blog post is one of the greatest scientific achievements of all time. Tutorials often mix up a tool's external model and internal model in a way that’s confusing for learners; it's helpful to be aware of this so that you can easily identify when it's causing you frustration. Spaced Repetition Helps You Remember Spaced Repetition been proven to be one of the best ways to encode new information in long-term memory. The idea is to quiz yourself at ever-increasing time intervals to minimize memory decay using the fewest number of repetitions. The Guardian wrote a great introductory article. Sleep and Exercise Take care of your body! It's more than just a vehicle for your brain. If you want to be able to stay focused and learn efficiently, getting adequate sleep and exercise beats the pants off caffeine and energy drinks. More tips? If you have any useful tips, please leave them in the comments! If you'd like more excellent resources on learning to program, check out the Community Picks: Learn Programming, a community-curated collection of the best books for learning programming. It includes a wide array of subjects, including introductory programming books, books on craftsmanship, and books on soft skills and interviews.

# Kubernetes with ELK Setup

## 3 months ago | Rocky Jaiswal: Still Learning

As it turns out this is my 100th post. The first one was published in March 2011 and a lot has changed since then. A lot of new technologies have come in and a lot of my posts have become obsolete. In all these years nothing has created more i ...

# Tips and Tricks for Beautifully Simple Mobile App CI

## 3 months ago | Dave Kerr: dwmkerr.com

In this article I'm going to demonstrate some simple tips and tricks which will help you build and maintain beautifully simple mobile build pipelines. These techniques can be applied to different mobile app technologies and integrated into almost any build system: Each tip is demonstrated in the sample apps in

# Testing HapiJS with Jest

## 3 months ago | Rocky Jaiswal: Still Learning

HapiJS and React are pretty much my go-to technology choices for web application development right now. While Jest works really well with React, on the HapiJS side I was ...

# Zen and the Art of Blowing Things Up

## 3 months ago | Daniel Higginbotham: Flying Machine Studios

The Dark Knight came out at the same time that I was becoming intensely interested in Buddhism, and the movie struck me as a kind of extended Buddhist parable, with Bruce Wayne as an icon of the suffering that results from clinging and the Joker as a very fucked up enlightened being. Here are some of my main reasons: (warning: spoilers!) Suffering and Impermanence Buddhism teaches that suffering comes from constantly scrambling for stability in an unstable world. Nothing is permanent, but we strive mightily to hold on to the illusion of permanence, only to suffer when reality once again asserts itself. In the scene where Batman is in the interrogation room beating the stuffing out of the Joker, the Joker just laughs and says, "You have nothing! Nothing to threaten me with. Nothing to do with all your strength." And that cuts to the heart of who the Batman is: a person whose reaction to the first shock of impermanence (his parents dying) was to dedicate his life to developing his strength so that he would never experience that pain again. The Batman's entire being is an exercise in doing just one... more... thing... to establish control. I mean, who would want to live that life? And here's the Joker, ready with the Zen slap: he tells Batman where to find Harvey and his girlfriend Rachel, giving him the illusion of control over who to save. And we know how that turned out: the Joker lied to the caped crusader, telling him Rachel was at one address, but actually Harvey was there. Batman races to save Rachel, only to find find Harvey instead. Nothing to do with all that strength. This really hit home for me because, at the time, I was in a relationship with someone that had a chronic illness. I could try to do everything to make her life less painful and more enjoyable, but there was only so much I or anyone could do. Natural Metaphors and Endless Desire At one point, the Joker says, "I'm just a dog chasing cars, I wouldn't know what to do if I caught one." Or something like that. This is a double whammy: "a dog chasing cars" is totally something a zen master would say, but besides that it expresses our human tendency to constantly strive for the next thing. We're all just dog chasing cars, not knowing what to do when catch one. You get a job: now you want a better job. You get a house: now you want a bigger house. Better to just say fuck it, put on some makeup, and start blowing up hospitals. No Self The Buddhist idea of "no self" is actually somewhat nuanced and I'm purposefully misrepresenting it here, but it would be difficult to argue that the Joker clings to any notion of self in the way that most of us non-enlightened psychopaths do. He gives multiple stories for how he got his scars, revealing the Buddhist truth that our sense of self is just a story we tell ourselves and that no one story is better than any other. He gives up his name and identity to become a fucking clown. And people really hate clowns! Interconnectedness One Buddhist teaching is the idea of interconnectedness: that we are all one, but not in the wavy-gravy way your high uncle used to ramble about. My take on the idea is that it's related to no self: you cannot point to a "you" that is separate from the world you exist in. It's a fallacy to believe your "you" is somehow different from the collection of experiences of the world, so that you are inextricably intertwined with the world. You can't point to one thing outside yourself and say "I am not this," because you are pointing at it you moron, and so in that moment who you are is a guy pointing at that thing, and life is the accumulation of such experiences of things outside of "you." ANYWAY I am totally not your high uncle, OK? Point is, the idea of interconnectedness is meant to foster a sense of compassion. You can see that at the end of the movie when the Joker plays his hilarious "blow up the other boat" gag. Two boats full of strangers become enlightened, refusing to do harm to people they haven't even met. The Dark Knight remains one of my favorite movies of all time, and it inspired a Batman obsession that took years to subside. (Ironically, obsession is a fairly un-Bhuddist behavior.) If you're a Batman fan too, check out Batman Community Picks for the best Batman books and movies. Or if you're interested in Buddhism, check out Buddhism Community Picks for the excellent books.

# Get up and running with OpenShift on AWS

## 5 months ago | Dave Kerr: dwmkerr.com

Setting up your own OpenShift cluster can be a little complex, but in this article I'll show you how to make it fairly painless.

# WFFM: Save to Database

## 5 months ago | Sumit Bajaj: Sumit Bajaj's Blogs

Web Forms For Marketers has become one of the essential component of Sitecore. Almost every website is using forms to capture the inputs from users and it is very common scenario to get the data stored in Database for reporting purpose. Here are few easy steps which can help you storing the form's data in SQL database.Download the WFFM - SQL Provider(Save To Database) and install it in Sitecore using Installation wizard. All physical files and Sitecore items will be stored in respective location.Once installed, you will notice that it has created a new Action under System-> Modules -> Web Forms for Marketers -> Settings -> Actions -> Save ActionsNow, we have to add connection string in configuration file which will help us storing the data in that database. You have to keep the name of connectionstring to 'wfm' only as same name is referred in WFFM module code.< add connectionstring="user id=your_db_user_id;password=your_db_password;Data Source=your_db_server;Database=your_db_name" name="wfm" >You are done.Now add the 'Save to Database' action on any WFFM form and start using it. Also validate the database and data should start getting stored in it.Furthermore, this module provides the capability of exporting the saved data in CSV format. We can do customization on it to export the data from different servers(CMS or CD) which I will explain in next article.Please don't hesitate to contact me at 'email.bajaj@gmail.com' for any Sitecore related query/scenario.

# Pointers in C and x86 Assembly Language

## 5 months ago | Pat Shaughnessy: Pat Shaughnessy

16GB of DDR random access memory my son used in his new gaming PC Recently I’ve been trying to learn how to read x86 assembly language. In http://patshaughnessy.net/2016/11/26/learning-to-read-x86-assembly-lang

# Creating a Resilient Consul Cluster for Docker Microservice Discovery with Terraform and AWS

## 6 months ago | Dave Kerr: dwmkerr.com

In this article I'm going to show you how to create a resilient Consul cluster, using Terraform and AWS. We can use this cluster for microservice discovery and management. No prior knowledge of the technologies or patterns is required! The final code is at github.com/dwmkerr/terraform-consul-cluster. Note that

# Learning to Read x86 Assembly Language

## 7 months ago | Pat Shaughnessy: Pat Shaughnessy

A 16-bit Intel 8086 microprocessor from 1978 (source: RodolfoNeres via Wikimedia Commons) Writing assembly language is

# Using Slack for Server Development

## 7 months ago | Dave Kerr: dwmkerr.com

I recently found a surprisingly helpful approach for server-side development which uses Slack in a creative way.

# Docker Registry with AWS & Let's Encrypt

## 7 months ago | Rocky Jaiswal: Still Learning

With pretty much all new projects moving to Docker and Docker managers like Kubernetes, the Docker Registry becomes the first piece of infrastructure that a team needs to setup. Sure there are public and private registries availa ...

# Simple Continuous Integration for Docker Images

## 8 months ago | Dave Kerr: dwmkerr.com

In this article I'm going to demonstrate a few tips and tricks which can make your life easier when you are building or maintaining Dockerfiles. The need for a Build Pipeline Do we really need any kind of continuous integration or build pipeline for Dockerfiles? There will be cases when

# Run Amazon DynamoDB locally with Docker

## 8 months ago | Dave Kerr: dwmkerr.com

tl;dr: Run DynamoDB locally using Docker: docker run -d -p 8000:8000 dwmkerr/dynamodb Try it out by opening the shell, localhost:8000/shell: That's all there is to it! DynamoDB Amazon DynamoDB is a NoSQL database-as-a-service, which provides a flexible and convenient repository for your services. Building applications

# Need a Second Opinion on Your Ruby Code? Ask Crystal

## 9 months ago | Pat Shaughnessy: Pat Shaughnessy

Running the Crystal compiler on your Ruby codeis like asking a second doctor for their opinion. When it comes to your health, you don’t hesitate to get a second opinion. Doctors don’t always agree, and a second doctor’s app

# Hello Kubernetes

## 9 months ago | Rocky Jaiswal: Still Learning

Introduction Pretty much everyone in the technology world has heard about Kubernetes by now. But before we dive into it, let's try and understand the problems it solves - Back when I started programming, servers were usually considered out of reach for us developer ...

# Effective Node.js Debugging

## 10 months ago | Dave Kerr: dwmkerr.com

If you are interested in improving your Node.js debugging skills, then check out my talk at the recent JSChannel 2016 conference in Bangalore: Comments and observations are always welcome!

# My Writing Process

## 10 months ago | Daniel Higginbotham: Flying Machine Studios

The letter below is a response to an email from a Twitter friend. For context: I've written some instructional material that's enjoyed success online, including Clojure for the Brave and True and Clean Up Your Mess: A Guide to Visual Design for Everyone. Robert asked me a few questions about my process. Hi Robert! You're in the unfortunate position of being my permission to write at length about my creative process without seeming completely self indulgent: someone's actually interested in listening to me describe the chaos between my ears! Be prepared to read way more than you asked for. How do you decide who you are writing for? This one’s key for me. When I’ve written in the past, I’ve struggled with knowing how much or how little to say. I’m curious to learn how you deal with that. First: I've found it useful to follow the standard advice and pick an individual or two and write for them. The argument goes that you'll find it much easier to choose words and have a consistent tone, and that's proven true for me. When I wrote Clean Up Your Mess, I was one of three programmers working in an office full of charming people who did business analysis for management consultants, and I wrote the guide for a couple of them that I had become friends with. These analysts produced powerpoint decks by the barrel, and every single one was ugly. Similarly, Clojure for the Brave and True started as a guide for a couple coworkers that I was mentoring. However, picking your audience is only half the process. The other half is picking who the author is. I'm going to go on a bit of a tangent to explain this. When I started writing Clean Up Your Mess, my personal life was a mess. In hopes of making it less messy I had been spending most of my free time reading Buddhist literature and listening to lectures by Thich Nhat Hanh and Pema Chodron (in fact, my site opens with a Thich Nhat Hanh quote). I was spending a great deal of time meditating and reflecting. (You're interested in Buddhism too, right?) One of the ideas that really grabbed me was that our self-conceptions are just stories we tell ourselves with no reality to them. I won't belabor the point here; suffice to say that I found it useful and powerful to be able to perceive my identity as a construct as ephemeral as smoke. Around the same time, I started taking improv comedy classes, where I would spend two hours a week constantly coming up with new, unique characters and living in them for a few minutes at a time. When you're sold on the idea that your day-to-day you is itself just a character, improv becomes way easier and more fun. It's also fun to do this in real life - like, recently my wife and I were at the grocery store and I decided my character was "Super Excited About Carrots Guy", and I started shouting "OH MY GAWD JESS CARROTS! THEY HAVE CARROTS JESS! CARROTS!" Everyone was laughing as they escorted me out! Anyway, during this time of buddhism and improv I was writing Clean Up Your Mess and when I sat down to write I got to play with new identities, new characters, and see which was the most fun. It became much easier to find words and keep a consistent tone when I decided on the author's character. So, you mentioned not knowing how much or how little to write. Knowing your character helps. In Clojure for the Brave and True, one of my editors would sometimes whittle down sentences to the bone, leaving only pure information; I would undo those edits with gusto, adding back the shape and texture of the author's voice. There's another aspect of writing instructional material, which is that 95% of the time you can take more time to explain something. Even if you're writing for experienced audiences, at least take the time to explain acronyms and jargon. How often and how much do you write? Not enough and not enough! Writing was easiest, however, when I had a consistent schedule of writing at least one hour every single day. Let me tell you about my garage. My garage is a living f*cking nightmare. It's like Cthulhu and the dread of the dark you had as a child made disgusting love and produced a horde of horrors that died in giant filthy clumps all over. At the beginning of the year I suppressed my gag reflex long enough to clean it out with the goal of setting up a photo studio, which I did, only to let it sit for three months. So three months later I go in there to actually take photos and guess what: it's a complete horror show, again! If I had only spent time every day or even every week maintaining it, I'm sure it would have been much easier to keep clean. If I had cleaned it out, all those tiny insect monsters wouldn't have been able to breed, there wouldn't have been two dozen spider egg sacs, etc. When I don't write consistently it's like that. I have to crawl into the nest of no one cares what you write and this time everyone's going to hate it called my mind and clear it all out before I can actually start writing. When I write consistently, on the other hand, it's actually quite pleasant! One more note: much of the writing process is research. Every time I find myself struggling to explain something, it's because I don't understand it well enough. When that happens I put down the keyboard and pull out the pen and notebook. I try to articulate the questions that will lead me to understand what I want to explain. I read and I draw diagrams and play with words until I feel like I understand the concept. Becoming aware that, for me, writer's block is a lack of understanding, has helped me be much more productive. Collaboration Who does your drawings? My wife! She's pretty great. Do you have someone who edits for you? I did when I worked with No Starch. They were awesome! Clojure for the Brave and True is much, much better because they kept pushing me to write more clearly and explain things more fully. For other projects, I'll ask friends to look at drafts. How much does it cost? I paid my wife in carrots. OH MY GAWD JESS THEY HAVE CARROTS! No Starch gets 85% of hard copy sales and 77.5% of ebook sales (or something like that). I hope this was helpful!

# Understanding Recursion

## 11 months ago | Daniel Higginbotham: Flying Machine Studios

During my Clojure training I've found that recursion routinely trips people up. It definitely tripped me up for a long time. I've tried to develop an explanation that's clear and intuitive, so if you're still scratching your head about recursion, read on! A classic recursion example is calculating n factorial, which is n multiplied by every natural number before n; 3 factorial is 6 (3 times 2 times 1), 4 factorial is 24, 5 factorial is 120. The code snippet that follows is a typical implementation of factorial; if you're reading this, then presumably it's confusing - which is great! It means that I haven't written this article for nothing. function factorial(n) { if (n == 1) { return n; } else { return n * factorial(n - 1); } } What makes this function recursive is that factorial calls itself. That's also what makes the function tricky; the function calls itself!? We're used to functions calling other functions to get work done. For example, this function uppercases a string and prepends "Yo, " to it: function yoShout(str){ return "Yo, " + str.toUpperCase(); } yoShout("gimme a donut"); // "Yo, GIMME A DONUT" In this tiny example, yoShout does its work by using the toUpperCase function. It's easier to understand than a recursive function because yoShout treats toUpperCase as a black-box abstraction. You don't have to tax your brain by loading toUpperCase's implementation details into your short-term memory. Let's re-write factorial to use function calls this way, with function's body calling another function in order to get its work done. To calculate 3 factorial, you could write a series of functions, factorial_1, factorial_2, and factorial_3, like this: function factorial_1() { return 1; } function factorial_2() { return 2 * factorial_1(); } function factorial_3() { return 3 * factorial_2(); } These functions feel safe and comfy. factorial_3 calls factorial_2, something we're completely familiar with, and likewise factorial_2 calls factorial_1. factorial_3 also does not care how factorial_2, just like in the string example. Unfortunately, these functions are also completely impractical; can you imagine writing factorial_1000? The recursive implementation doesn't have this problem. My suggestion is to try seeing the recursive implementation from the same perspective as the nonrecursive imiplementation. Here's the code again: function factorial(n) { if (n == 1) { return n; } else { return n * factorial(n - 1); } } You can look at this and say, "Oh, if n isn't 1, then this function does its work by calling some black-box function named factorial with the argument n - 1." You can look at the call to factorial(n - 1) as a call to a completely different function - one that just happens to have the same name and algorithm. That's it! I hope it helps. If you've been confused by recursion, I'd love to hear your feedback!

# Pi Calculation with Elixir

## about 1 year ago | Rocky Jaiswal: Still Learning

As a programmer one is always searching for better tools, practices and programming languages. For example, working with Clojure makes me a better programmer, it provides me the ability to write functional, succinct code that runs fast and works on the well-tuned and battle-tested JVM. Looking at ...

# F#: Disabling SSL Certificate validation

## about 1 year ago | Kristof Mattei: Kristof's blog

Yesterday I wanted to download some content off a website with F#, however unfortunately the certificate of the website was expired. let result = try let request = "https://somewebsite/with/expired/ssl/certificate/data.json?paramx=1&paramy=2" |> WebRequest.Create let response = request.GetResponse () // parse data let parsed = "..." Ok parsed with | ex -> Error ex If we execute this, … Continue reading "F#: Disabling SSL Certificate validation" The post F#: Disabling SSL Certificate validation appeared first on Kristof's blog.

# F#: Disabling SSL Certificate validation

## about 1 year ago | Kristof Mattei: Kristof's blog

Yesterday I wanted to download some content off a website with F#, however unfortunately the certificate of the website was expired. let result = try let request = "https://somewebsite/with/expired/ssl/certificate/data.json?paramx=1&paramy=2" |> WebRequest.Create let response = request.GetResponse () // parse data let parsed = "..." Ok parsed with | ex -> Error ex If we execute this, … Continue reading "F#: Disabling SSL Certificate validation" The post F#: Disabling SSL Certificate validation appeared first on Kristof's blog.

# HTTP Compression and Performance tuning

## about 1 year ago | Sumit Bajaj: Sumit Bajaj's Blogs

With the advancement of technology and exceeding expectations of users, one has to be very careful designing a website. Performance is one of the key elements for success of an application. Even if, you have designed the application with uttermost care and rock solid architecture, there are few key areas in which you have to be really vigilant. HTTP Compression is one of those pivotal spaces.HTTP compression is the technique to compress static and dynamic content which improves the transfer speed and performance of a website.Steps to keep the compression ON for a website. Here the demonstration is given for IIS based website.1. Open IIS (inetmgr)2. Goto website. Right side will show all components of that website3. Click on 'Compression' module and verify that both the checkboxes are checked if you need static and dynamic content to be compressed.4. Click 'Mime Types' and check 'application/x-javascript' is added in the existing mime types. If not, add it.5. Reset IIS, browse website and verify that JS is getting compressed now.Web.Config SettingsHere are all the mime types and gzip information which should exist for a website if compression needed, either in IIS settings or in web.config.Note: Include it in web.config if configuration file also get deployed with every build.Section to include in <system.webserver></system.webserver><system.webServer><httpCompression> <staticTypes> <add mimeType="text/*" enabled="true" /> <add mimeType="message/*" enabled="true" /> <add mimeType="application/javascript" enabled="true" /> <add mimeType="application/x-javascript" enabled="true" /> <add mimeType="image/jpeg" enabled="true" /> <add mimeType="*/*" enabled="false" /> </staticTypes> <dynamicTypes> <add mimeType="text/*" enabled="true" /> <add mimeType="message/*" enabled="true" /> <add mimeType="application/javascript" enabled="true" /> <add mimeType="application/x-javascript" enabled="true" /> <add mimeType="image/jpeg" enabled="true" /> <add mimeType="*/*" enabled="false" /> </dynamicTypes> <scheme name="gzip" dll="%Windir%\system32\inetsrv\gzip.dll" dynamicCompressionLevel="4" /> </httpCompression></system.webServer>After compression is ON:Response header of a JS file being loaded in website. 'Content-Encoding: gzip' shows that it is compressed.Useful toolsThere are several webistes which can help you detect, if your website/CSS/JS is compressed or not. You should check css/js or website seperately to make sure that all static medias are compressed. One of the examples website is given here.Check CompressionFor further detail, you can contact me www.bajajsumit.com. Please share your feedback if you find the article useful.

# Testing the Docker for Mac Beta

## about 1 year ago | Dave Kerr: dwmkerr.com

I've finally had a chance to install the new Docker for Mac Beta and give it a whirl, here are my experience so far!

# Is it worth persevering with Golang?

## about 1 year ago | Dave Kerr: dwmkerr.com

After perhaps 10-20 hours of learning, coding and messing around, I'm wondering - is it worth persevering with Golang?

# What's your Vim Name?

## about 1 year ago | Dave Kerr: dwmkerr.com

I'm a few weeks into moving to Vim as my main editor, I've stopped crying and shaking mostly (at least about my editing ability). Now I'm wondering: what's your Vim name? And who's got the best one? As far as I can work out, my Vim name is: Replace everything

# Quick Tip: Sending Newlines with cURL

## about 1 year ago | Dave Kerr: dwmkerr.com

Yikes, this took far too long to figure out! I have a service which takes plain text multiline input and outputs an object for each line, something like this: Input Line 1 Line 2 Line 3 Output [ {line: "Line 1"}, {line: "Line 2"}, {line: "Line 3"} ] There's a bit more

# Classes and patterns in Node.js

## about 1 year ago | Rocky Jaiswal: Still Learning

This week we had the awesome Node.js 6.0.0 release! With the 6.0.0 release Node.js has 93% of the ES6 features implemented. In this short post we will look at few particularly interesting features including "classes in JavaScript", ...

# Moving from React + Redux to Angular 2

## about 1 year ago | Dave Kerr: dwmkerr.com

I'm going to share my experiences of experimenting in Angular 2, as someone who needs a pretty compelling reason to move away from React/Redux!

# Learn Docker by building a Microservice

## about 1 year ago | Dave Kerr: dwmkerr.com

If you are looking to get your hands dirty and learn all about Docker, then look no further!

# Setting up web server and continuous integration

## over 1 year ago | Sumit Bajaj: Sumit Bajaj's Blogs

Apart from creating website & app-pool in IIS, there are several steps which need to be performed when setting a new website on server.Setup Web ServerThere are few activities which you have to perform on Web Server:1. Install Web Deploy [Download]2. Install URL Rewrite [Download]3. Make Sure .Net Framework feature is ON in Windows features4. Create a standard user which could be used to deploy files to web server after successful build5. Open "services.msc" and check that 'Web Deployment Agent Service' is running with the standard user credentials created in Step 4.6. Run App pool and website with same standard user which is created in Step 47. Reset IIS ServerContinuous IntegrationThere are several tools which are being used for continuous integration but they perform same functions when we discuss about build and deployment. In this example, we are referring Jenkins [Download].If msdeploy or any relevant command is being used to deploy files on web server, same standard user credentials should be used to copy the content else it will throw unauthorized exception.Common ExceptionsAn item with the same key has already been added.Solution: It can be resolved by checking Mime types. There is a probability that same Mime type is being added by web.config which is there in IIS already. In IIS 8, there is not need to add Mime types manually.Website is appearing but css/font is not loading.Solution: Open dev tools(if its chrome browser, press F12 key) and check if in console you are getting errors like 404, 500 etc. Check if css/font files are present in the right folder. If gulp or grunt is being used, make sure it is compiling the files without exception.If any CMS is being used then there might be CMS related errors.Sitecore has no necessary permissions for reading/creating counters. OR Sitecore publishing screen is showing 'Initializing' but not publishing anything.Solution: Application pool user should be member of 'Performance Monitor User' group. Add user to this group and restart IIS. Even after this, if it does not work sitecore counter can be disabled by setting counter value to false. For example: <setting name"counters.enabled" value-"false"/>Let me know if you still get any exception. Have a nice day!!

# Is Your Postgres Query Starved for Memory?

## over 1 year ago | Pat Shaughnessy: Pat Shaughnessy

Like a patient with low blood pressure, a slow SQL query might not be getting the memory it needs. For years or even decades, I’ve heard about how important it is to optimize my SQL statements and database schema.

# Get all Items inheriting another template

## over 1 year ago | Sumit Bajaj: Sumit Bajaj's Blogs

Working on different templates and Sitecore items, its very common requirement to knowhow many items are created with a specific templatehow many template are inheriting a base template or another templateSitecore provide this feature out of box however you need to write query to fetch the required items.Open Sitecore IDE (http://localhost/sitecore/shell/default.aspx?xmlcontrol=IDE)Goto Tools -> XPath BuilderWrite XPath Expression:/sitecore/templates//*[contains(@__Base template,'{1FE1328B-375B-4548-A53E-344FA61ACC90}')]In result section, it should show all templates which are inheriting base template with ID {1FE1328B-375B-4548-A53E-344FA61ACC90}.Similarly, query /sitecore/content//*[@@templatename='Promotional Page'] should show all pages (under content) created with 'Promotional Page' template.On top of results, it shows the count of items and time taken to fetch the items.We can use fast query as well instead of query.Note: The above queries are example of specific requirement. Query can be modified to get required items according to project need.URL: Sitecore Query and Fast Query

# Weather with Reagent

## over 1 year ago | Rocky Jaiswal: Still Learning

In my last blog I talked a bit about React and ClojureScript. In this post we will look at a simple Reagent app that fetches the weather using the http://openweathermap. ...

# React Router Comparison

## over 1 year ago | Rocky Jaiswal: Still Learning

React and Redux are game changing technologies. The architecture principles they are based on seem to be sensible and rock solid. Redux architecture revolves around a strict unidirectional data flow, with a central ...

# Announcing Job Search Sanity

## over 1 year ago | Daniel Higginbotham: Flying Machine Studios

One of the least fun experiences in my life was getting fired twice in three months back in 2008 when the economy decided to go all YOLO and drive off a cliff with its middle finger waving out the window. The first time, I was a wreck. I was in a relationship with someone who had a chronic medical condition and the attendant medical bills. As the sole money earner, I was pretty bummed! Every day I felt dread and panic as I pored over job listings. I made many stress-induced mistakes like emailing the same contact twice or forgetting phone interviews. But somehow I found a job at a startup pretty quickly, only to be regrettably let go a couple months later because they were running out of money. This time, I did things differently. I took a Getting Things Done inspired approach to the job search. Approaching the search in an organized, methodical way made me feel in control. It also gave me confidence that I was making real progress on finding a job because I could actually see all the steps I was taking. At the end of the day I knew I had done what I could to move forward. Today I'm releasing a free web application, Job Search Sanity, to help others do the same. It helps you keep track of each job opportunity and the next actions you need to do to move forward. It also keeps cover letters and interview remindres in place. And one of its best features is that it lets you save your job searches on the site so you can keep them all in one place instead of visiting dozens of sites every day. If you're looking for a job and feel overwhelmed, then please give it a try! If you know someone who's looking for a job, please send them a link! Personal Notes The main thing that motivated me to create this site was seeing my brother struggle with finding employment after graduating with a Pharm.D. (doctor of pharmacy) degree last year. After spending a decade putting himself through school, he had the modest expectation of finding decent-paying, stable work. Instead, he found that the pharmacy market had radically changed while he was getting his degree, and jobs were scarce. I can only imagine how crushing it would feel to commit so much of your life (and accumulating large student loan debts) to learning profession, only to find that the rules had changed and there was actually little demand for your skills. To find that the future you've been working toward for so long has vanished, replaced with utter uncertainty. It was a rough time for him, but thankfully he did eventually find a job as a pharmacist. While he was looking, he came to live with me, and I was so glad that I was able to help in some way (and that I got to spend so much time with him), but part of me wished I could have done more. Cut to the present day, where my wife has been looking for a better job for a while, and I can see the stress affecting her in similar ways (though to a much lesser degree, thankfully). All of which is to say - I know that looking for a job can be incredibly stressful, and I hope that by providing this free app I can help people in similar situations. I kind of need to make something that I actually accept payments for soon, but for this site I didn't want their to be any barriers to signing up and using it. Perhaps I'll figure out way to monetize it, but for now I'm proud of the site and I'll count it a success if it helps even a dozen people as they find a job. Development Notes Job Search Sanity was built using: The Boot build tool. Boot made it easy to integrate a Clojure backend, ClojureScript frontend, and Sass compilation Liberator, to structure the handling of back-end API calls Datomic for the database re-frame as the lightweight front-end structure imposed on reagent I absolutely loved working on the site because the tools made it so much fun. One of my personal goals was to stretch myself design- and UX-wise, and the above programming tools made that possible by making it so simple and easy to implement the basic functionality. ClojureScript has come incredibly far in the past couple years. A year or two ago I looked at it but stuck with Coffeescript because cljs looked like a pain in the ass to use, but that isn't the case any longer. The only downside here is that, once again, Clojure has spoiled me, and I never want to go back to my previous tools.

# A Look at How Postgres Executes a Tiny Join

## over 1 year ago | Pat Shaughnessy: Pat Shaughnessy

Reading the Postgres source code is like attending a free Computer Science lecture, complete with working examples. Aside from saving and retrieving data, the primary feature of a relational database is the ability

# Pi Calculation with Clojure

## over 1 year ago | Rocky Jaiswal: Still Learning

A while back I wrote a post on using Akka with JRuby to calculate the value of pi. Since I am learning Clojure these days I thought it would a good idea to implement the same pi calculation algorithm using Clojure and core.async. The i ...

# Rejection Sampling

## over 1 year ago | Pranav Modi: pranavmodi.com

Continuing the exploration of simple sampling methods from the last post. Unlike the Normal or the Uniform distribution, arbirary p.d.f's cannot be sampled directly. If we need to calculate the expectation of $$f(x) = e^x$$ and p(x) looks like this – Here we cannot use Simple Monte Carlo, as there is no direct … Continue reading Rejection Sampling →

# Be careful with npm shrinkwrap

## over 1 year ago | Kristof Mattei: Kristof's blog

Recently we had the issue that we used version x of an npm package. However in the course of time this package was updated by the author and contained a critical bug, which broke our AWS deployments. Locally this was no issue because we had a version installed that satisfied the version requirements. In order … Continue reading "Be careful with npm shrinkwrap" The post Be careful with npm shrinkwrap appeared first on Kristof's blog.

# Be careful with npm shrinkwrap

## over 1 year ago | Kristof Mattei: Kristof's blog

Recently we had the issue that we used version x of an npm package. However in the course of time this package was updated by the author and contained a critical bug, which broke our AWS deployments. Locally this was no issue because we had a version installed that satisfied the version requirements. In order … Continue reading "Be careful with npm shrinkwrap" The post Be careful with npm shrinkwrap appeared first on Kristof's blog.

# Why Clojure's a Great Next Language for Rubyists

## over 1 year ago | Daniel Higginbotham: Flying Machine Studios

HAVE frothing at the mouth YOU flailing arms CONSIDERED eyes are unfocused and mad LISP flipping furniture over — @ra If you're a Rubyist itching to learn a new language, then I want to convince you (using only a minimum of mouth frothing and chair flipping) that Clojure's a great pick for you. Please excuse me if this article reeks of the glassy-eyed fanaticism of the true believer, but the fact is that I think Clojure is crazy stupid fun to use, and intellectually rewarding to boot. I fell in love with Ruby back in 2005, and since then only Clojure has been able to elicit the same level of affection. I think this is because Clojure has the same fundamental attributes that make Ruby so appealing: it's simple, it's powerful, and above all, it's fun. The rest of this love letter cough I mean, blog article, is about how Ruby and Clojure exhibit these attributes in very different ways, and how Clojure's different approach to computation makes it fascinating and rewarding to learn. My first exposure to Ruby was DHH's whoops-laden Ruby on Rails demo. That video saved me from the Lovecraftian horror that was PHP circa 2005. You may have had a similar experience, with Ruby rescuing you from C++ or Java or COBOL or whatever. It's a vast understatement to say that, compared to PHP, Ruby is elegant. Whereas PHP seemed almost to strive for inconsistency, Ruby employs only a few, simple ideas: everything is an object, you advance your program by sending messagse to objects, and message dispatch is governed by a couple easily-understood rules. Clojure is also a very simple language. It wouldn't be a stretch to say that simplicity is one of the core tenets of the Clojure philosophy; its creator, Rich Hickey, has given a number of talks elaborating on what it means for something to be simple, including Simple Made Easy and Clojure, Made Simple. Clojure's simplicity, however, takes a radically different form. In Clojure, you primarily care about two things: data and functions. You pass data to functions and get new data back. Yes, there's other interesting stuff like state management constructs and macros, just as there are other interesting aspects of Ruby like modules and blocks. But the heart of Clojure is so simple any eighth grade algebra student can understand it: hand some value to a function, and it hands you a new value back. "But wait a minute," you might be thinking, "You can't just pass data around like that. Haven't you read POODR? What about encapsulation? What if those functions mutate your data?" In Clojure, data is immutable. You can't change existing data, you can only derive new data; when you add 3 and 4, you don't change 3 or 4 to make 7, you derive 7. If this sounds crazypants and impossible to work with, all I can do is assure you that it does work (and point you to this book I wrote available free online, Clojure for the Brave and True which explains how) and hope that your intellectual curiosity will motivate you to explore this crazypants paradigm that lots of people seem to love. Here's a teaser: many of the problems addressed by object-oriented design simply aren't problems in Clojure. You don't have to care about inheritance vs. composition because behavior isn't chained to data. You don't have to care about data hiding because there's no risk that some object somewhere will silently change it. As a Rubyist, you know that simplicity buys you power, where power is defined as the ability to express computational ideas concisely. For example, Ruby's blocks allow you to write anonymous algorithms, something that's impossible in C. Another example: Ruby's simple method dispatch scheme makes it easy for you to reason about and design robust programs. It lets you easily extend code and buys you reuse through multiple inheritance. Most enticingly, it lets you do metaprogramming. Clojure's simplicity also buys you power. As a Lisp, Clojure employs a syntax which just so happens to mirror the internal abstract syntax trees that represent Clojure code. I'm going to wave my hands a bit here and say that this lets you use macros, the most powerful metaprogramming tool available to any language. In the Ruby community, we like to talk about code that writes code; macros take this idea to a whole different level. It's not an exaggeration to say that Ruby's metaprogramming system provides only a subset of the capability provided by Lisp macros. Super duper hand wavy, I know, but the point is: if you like how powerful Ruby is, you will lose your flipping mind over how powerful Clojure is. Macros let you easily implement ideas from all corners of computer science. It's not an accident that Clojure has so many libraries that let you use different paradigms. There's core.logic for logic programming, instaparse for building parser generators, core.typed for haskell-ish typed programming, and much more. And macros aren't even the coolest part. I'll let you in on a secret: macros are the flashy, shiny bait that wild-eyed Clojurists lay out to ensnare curious programmers. Nay, even more powerful is Clojure's design of programming to abstractions. This design makes it incredibly easy to reuse your code and extend existing code. Of course I can't tell you how in the short space afforded by this digital outburst, but you'll grow as a programmer if you learn about it. These last two paragraphs also hint at what makes Clojure so dadgum fun. First, by learning Clojure you get introduced to one of the most loved and respected computational traditions, Lisp and the lambda calculus. It also has a clear philosophy, articulated by Rich Hickey, that will make you a better programmer. Not only that, other programming vistas become more readily accessible. Second, Clojure is a joy to write. Here's a quote from Matz (Ruby's creator) on his design philosophy: By using Ruby, I want to concentrate the things I do, not the magical rules of the language, like starting with public void something something something to say, "print hello world." I just want to say, "print this!" I don't want all the surrounding magic keywords. I just want to concentrate on the task. That's the basic idea. So I have tried to make Ruby code concise and succinct. Clojure, likewise, is concise. It lets you focus on solving the problem at hand rather than figuring out the magic whatever. People are falling in love with Clojure, spending their nights and weekends learning it hacking with it, because the experience is its own reward. If you're looking to stretch yourself and explore more of what the world of programming has to offer, then I recommend Clojure to you with all of my crazed heart. Here are some resources for getting started: Clojure Distilled, a very short overview of the language Clojure for the Brave and True, my own full-length crazypants introductory book Living Clojure, an excellent introductory book by Carin Meier, someone who BUILDS ROBOTS LispCasts for those of you who prefer video The Rich Hickey FanClub lists all his talks Now go out there and start learning some Clojure!

# Simple Monte Carlo

## over 1 year ago | Pranav Modi: pranavmodi.com

Often in Machine learning and Statistics, we are required to sample from a density function p(x). One of the the most commonly encountered scenarios is when the expectation of f(x) needs to be calculated. $$\mathbb{E}[f(x)] = \int_{-\infty}^\infty f(x) p(x) dx$$ If this integral is not computable analytically then approximate inference methods are the … Continue reading Simple Monte Carlo →

# Looking for Beta Testers

## over 1 year ago | Daniel Higginbotham: Flying Machine Studios

Over the last couple months I've been working on a web site that helps job seekers reduce stress by following a structured, methodical process, and the site's ready for some beta testing. If you'd like to help out, please sign up for the beta test! This isn't a unicorn-disrupting once-a-generation app, just a simple site to help people during a stressful process. For the beta test, I'm just looking for feedback on what's broken, what's confusing, and what could be useful but isn't implemented. Thanks! P.S. in case you're wondering, the site's all Clojure, with compojure/liberator/datomic on the backend and reagent and re-frame on the frontend.

# Get started with Compojure & ClojureScript

## over 1 year ago | Rocky Jaiswal: Still Learning

Clojure is probably the programming language that has fascinated and intimidated me for the longest time. I tried to pick it up many times and gave up an equal number of times. However, it was getting harder and harder to ignore ClojureScript's rising popularity and its awesome integration with Re ...

# Why I wrote Clojure for the Brave and True

## over 1 year ago | Daniel Higginbotham: Flying Machine Studios

It seems weird to say that I'm almost painfully filled with gratitude for all the good shit in my life, and that that was what motivated me to start writing a free programming book, but that's the truth. Before I started writing Clojure for the Brave and True back in 2013, I had been deliberately trying to figure out what I could do to improve other people's lives even just a smidge. By that point I had been doing a gratitude practice (just spending a few minutes to think of three things I was grateful for) regularly for a year and a half, and felt that my life was so full with good shit that I felt almost obligated to do something for others so that they'd have more good shit in their lives. "Obligation" might seem strange here, and it's not 100% what I mean. It's hard to accurately put the feeling into words. Someday I'd like to take the time to do a good job writing about it, but for now - My life experiences have instilled in me a belief that kindness and generosity are obligations. To take just one experience: for years, I witnessed firsthand the kind of suffering that chronic illness can inflict on someone. That was just nature doing it's thang, cruel, impersonal, implacable. But it was compounded by the constant minor (and sometimes major) abuses delivered by people. Life is painful enough without humans heaping additional indignities on each other. Beyond this baseline of "don't be an asshole" (incidentally, that's the central tenet of my personal ethics), I think it's imperative to learn to live with kindness, love, and generosity. The bleak perspective on this is that the ship is going down for all of us, and the only thing we have to hold on to is each other. The not-bleak perspective is that we are social creatures, wired to find fulfillment in contributing to each others' happiness; that our greatest joys are found in human connection. Which is why I wrote a programming book featuring hobbit violence, man-eating trolls, and mopey teenage vampires! Really, though, programming is a huge part of why my life is so full of good shit. I grew up living in poverty, and now I make a very comfortable living doing an activity that I genuinely enjoy. I have great coworkers, good health insurance, I live in a good house and have a decent car, and I'm confident I can provide for my family. I even have enough free time for hobbies and friends. So, I wanted to provide something free to the world to help others improve their lives. Learning Clojure has personally made me a much better programmer, and I think others can benefit from it just as much. In learning Clojure, you learn a new way of thinking about programming. It's intellectually rewarding and it has immense practical value; it makes your life as a programmer a lot easier. Plus, there's something romantic about learning a language that carries on a 60-year legacy. Like you're engaging in a tradition that extends far beyond you. And it's fun! Clojure feels like something you'd want to use in your spare time, for fun, but what's better is that you can actually get paid to use it. The other main reason I wrote the book was that I needed some way to tell the world about the were-Simmons. The danger is real! Wake up, sheeple!