John Hamelink

Tweaking Emacs for Ruby Development in 2023

Thu, 06 Jul 2023 22:00:00 +0100

Preamble

Since I started a new job in April, I’ve been spending the majority of my time with legacy Ruby code for the first time since 2017 (I’d been mainly working on Elixir and Typescript codebases between then and now).

Before my start-date at the new job, I spent some time setting up a basic Emacs configuration for Ruby. I’d made a good start, but with all those unknown unknowns swimming around, I was only able to make vague assumptions about what I needed. I’ve since done a bunch more tweaking to get a configuration that works well with the development environment in this company.

Configuring DNS for Kubernetes Development

Thu, 28 Nov 2019 11:14:00 +0000

In the intervening 3 years between my last blog and this one, I’ve been on quite the adventure, partly involving setting up multiple Kubernetes clusters.

While I’m absolutely sold on the ability of Kubernetes to slash server budgets, to drastically improve deployment compared with much of the home-grown CI systems out there (I am also guilty of this sin), and to provide a coherent configuration system that’s free of vendor lock-in poison; in my new occupation I’m focussed on improving the developer onboarding experience. Allow me to explain further below. (If you don’t care and just want the juicy stuff, feel free to skip down to the section entitled, “How to configure DNS for Kubernetes Development”).

OpenSSL and Elixir

Thu, 17 Mar 2016 12:41:00 +0000

If you’re using the latest OpenSSL package from Homebrew, you might come across an error similar to this one from time to time:

==> fast_tls (compile)
Compiled src/fast_tls_app.erl
Compiled src/p1_sha.erl
Compiled src/fast_tls_sup.erl
Compiled src/fast_tls.erl
Compiling c_src/fast_tls_drv.c
c_src/fast_tls_drv.c:21:10: fatal error: 'openssl/err.h' file not found
#include <openssl/err.h>
         ^
1 error generated.
ERROR: compile failed while processing /Users/john/Public/fap/api/api-2.1/deps/fast_tls: rebar_abort
==> api
\* (Mix) Could not compile dependency :fast_tls, "/Users/john/.asdf/installs/elixir/1.2.3/.mix/rebar compile skip_deps=true deps_dir="/Users/john/Public/fap/api/api-2.1/_build/dev/lib"" command failed. You can recompile this dependency with "mix deps.compile fast_tls", update it with "mix deps.update fast_tls" or clean it with "mix deps.clean fast_tls"

The reason why this error is happening is because OpenSSL header files required to compile this (in this case) rebar module are in homebrew’s /usr/local/opt directory. We can simply fix this by setting LDFLAGS and CFLAGS before compiling:

Elixir/Erlang and autoscaled EC2 servers - how to make them best buddies

Thu, 03 Mar 2016 02:22:00 +0000

At Find a Player, we’ve been trying to figure out how we want to cluster our Elixir servers - so that they can share state between each other - recently. Because we come from ruby (ie, not a high-availability background), when we want to discover other machines in a network we’d traditionally use something like Consul - of which I wrote a ruby library called Diplomat (which admittedly needs some love).

However, after chatting with Gordon Guthrie - a guy who’s been working with Erlang for over 13 years - over twitter, he told us to checkout :net_adm.world/0. Which does pretty much exactly what we want, straight out of the box.

Pull-based Deployment at Find a Player

Mon, 21 Sep 2015 13:18:00 +0100

Most startups care a lot about scalability. Find a player is no different. A lot of people have asked me how I went about designing Find a Player’s deployment system, so I thought I’d document it here at a high level.

Background

Before we embarked on this project, we were using ansible to handle push-based deployments to multiple servers. However, when we looked into using an autoscaler in AWS to handle traffic spikes, we realised that a push-based deployment no longer makes sense as it requires an external widget to run the deploy on a server if it is spawned. It became very clear that it made much more sense to have the spawned server itself run the deploy locally on itself.

My Perfect Livecoding steam for OSX

Mon, 31 Aug 2015 12:00:00 +0100

I’ve been interested in live streaming for a while now. I’ve been playing with Livecoding.tv on and off, and through this experience I’ve had to deal with the crappy internet connections and configuration complications I’ve had to figure out. I thought I’d document my current configuration so that I might help make other potential streamers’ experiences a bit smoother.

Prerequisites

I’m using OBS to stream on osx Yosemite. I’m using a 15" Macbook Pro Mid-2014. I’m using Bluetooth headphones which complicate my setup somewhat. My machine has 16GB of ram, a 2.2Ghz core i7, and an SSD. Your mileage may vary - this is what works for me on my connection, with my computer’s spec. If you interent connection is more or less symetric than mine, this configuration will probably be sub-optimal, but hopefully it will point you in the right direction.

I've been tying my laces all wrong

Sun, 24 May 2015 15:30:00 +0100

When I was young, I had trouble doing something that most young children struggle with - tying my shoe laces. I am left handed and my parents are both right handed which made learning even more difficult for me than for other children. Eventually, an older boy who was also left handed taught me and the rest was history.

Except that’s not the end of this story - I always had problems with tying shoes ever since. To be clear, it wasn’t the tying of the shoes that was a problem as I grew into my teens and beyond - it was the fact that my knots always seemed slack, which led to me having to re-tie my shoes constantly, and then eventually giving up and just tucking them in, leading to backpain and bad posture.

Consuming Nested API Routes with Ember

Sat, 28 Feb 2015 21:39:00 +0000

At the time of writing I’m learning Ember-cli for the first time. It’s pretty tough as there’s not too much up-to-date documentation out there, but I’m slowly getting there, and I’m beginning to feel the power it brings.

One of the things I’ve been finding especially difficult is grokking how Ember consumes API data - specifically how it decides upon what the route it wants to consume looks like.

After hours of fruitless Googling and reading, I relented and hit IRC: #emberjs on Freenode to be specific. After speaking to a few helpful fellows on there, it became clear that Ember was not easily able to consume nested API routes just yet. Damn! That makes scoping your API data quite hard!

Joining ScreenHero with Slack Credit

Thu, 29 Jan 2015 10:00:00 +0000

Preamble

You may have heard of Slack before - a brilliant team chat service that raised $180m from the likes of Andressen Horowitz, Google Ventures, Kleiner Perkins and Accel. Very cool.

Well, on Wednesday Techcrunch posted an article announcing slack’s aquisition of Screenhero, a Ycombinator allum who have a really slick tool for remote pairing and screensharing.

This provides some really interesting prospects for slack users - being able to remotely debug or collaborate on issues through Screenhero directly is the first thing that comes to mind. Wouldn’t it be cool if we could all try it out before it becomes fully available on Slack? Unfortunately Slack disabled Screenhero registrations for all new users, but made all existing memberships free.

Making Unite.vim use the project root directory

Fri, 31 Oct 2014 01:18:00 +0000

I’ve been using vim for quite a while now - I think it’s about 3 years . Over the short 3 year journey, I’ve built up a pretty massive vimrc file which I add & tweak almost every day. Over the past week I decided to make the switch over to Unite.vim, but coming from ctrlp, I wasn’t satisfied with the default behaviour.

Problem

There are plenty of ctrlp snippets out there which approximate ctrlp’s behaviour, but one thing they don’t focus on is ctrlp’s ability to find your project root and search within its context. For me, this functionality was what took ctrlp from an amazing vim plugin, to something that made massive improvements to the speed of navigation, and ultimately, my productivity.

Distributed Web Systems with Consul, Diplomat, Envoy and HAProxy

Thu, 24 Jul 2014 01:30:00 +0100

As part as my never-ending quest to improve how I build cool things, I’ve been working for some time on building out infrastructure to help automate and monitor how my apps and servers are doing. I’ve written about horizontal scaling before, but today I’d like to get into one specific facet of its implementation: automated network discovery, and how we use it at FarmGeek to build reliable applications.

The Problem

So lets say you have a few servers - a node balancer, two application servers and a database server, for example. Everything’s working fine until BAM, one of your application servers crashes. To make things worse, in this scenario for an unexplained reason nobody finds out about this. However your HAProxy checks work and so the node leaves the connection pool as expected.

11 Things windows users might not know about Linux

Sat, 17 Nov 2012 23:43:00 +0000

As an avid Linux user for over 5 years, it still surprises me how many people don’t know basic things about Linux which make it so appealing to people like me. If you’re thinking about using Linux for the first time, or perhaps you’ve only just heard about it, here are a few things you might now know that might interest you:

1: Linux isn’t an operating system

Linux is actually the name given the “kernel” of one type of operating system. There are hundreds of thousands of Linux distributions for you to choose from. Linux draws its inheritance back from UNIX which was a proprietary operating system back in the 70s. We call the entire thing “Linux” because its easier and simpler for people who are new to Linux. Each one of those versions of Linux is referred to as a “distribution” or “flavour”. Ubuntu is a popular distribution of Linux, as is RedHat, Fedora, SuSE and Debian. Some people like to call linux GNU/Linux, because the operating system runs a suite of tools called the GNU toolkit on top of its self, in order for it to be complete.

Testing NodeJS with Jenkins

Tue, 13 Nov 2012 18:00:00 +0000

NodeJS is awesome. I’ve used it for many pet projects and have worked on commercial projects which have made good use of Node in sticky situations. When it comes to testing Node, we’re spoiled. My favourite testing framework is Mocha and my favourite testing library is should.js. We’ll be using that alongside Jenkins to build an automated test suite for our demo repository.

You Will Need

Mocha

Mocha is our testing framework. We use it to describe the tests we want to make.

The Green Developer

Mon, 12 Nov 2012 18:16:00 +0000

A good developer is energy conscious. A good developer understands the impact he has on the environment around him. A good developer is able to take all these things and use them to make a positive impact in his universe. A good developer is a green developer.

A green developer? What are you smoking?

A green developer understands how to build in blocks: he must master the art of software engineering versus software developing. What sets the software engineer apart from the developer is not speed, agility or knowledge, it is the ability to recognise and compartmentalise everything he does into reusable chunks. Why? Simply because reusable code means better code and also half the code.

What makes for a Good Development Lead?

Sun, 11 Nov 2012 21:31:00 +0000

Throughout my career so far, I’ve mostly worked alone. When I say alone, I’ve often worked alongside other people, but ultimately I’ve been paying them, or I had made the choice about whether they were suitable for the project (or for me) or not. They’ve mostly not been working on the same thing I’ve been working on either.

Ultimately, I’ve been the leader of the projects I’ve worked on during most of my freelance career. While at my current fulltime job however, due to the nature of the work I was doing there, I often had to work with other people who I couldn’t choose. This was a great new experience for me, with some terrible 3rd parties from other companies I had to integrate with, and some truly amazing developers I got the chance to work alongside. I learned a lot about what I look for in a leader during my time there, based on excellent leadership skills I saw working with some of the people I worked with, and with other people I saw (mostly in other companies I’m happy to report) make mistakes, I learned how I myself could strive to be that golden leader I wanted so bad. While I don’t claim to be perfect, I feel I have manage to construct a reasonably good guideline on how I should try to conduct myself in order to be the leader I would want to lead me.

Code is Poetry

Fri, 09 Nov 2012 22:19:00 +0000

I once read a much better article than this one by Matt Ward that attempts to show the similarity between code and poetry. Matt shows how the flow and syntax of good code, that abstract minimalism and lowest common denominator approach, is actually very similar to that of a poem.

I agree with everything Matt says, but I felt the article was a little lacking in showing how the coder can be a poet in order to achieve greatness and self-fulfillment (that’s what poetry and coding are partly about, in my opinion). To this end, I’ve compiled some advice I’ve learned by myself or from others over the years in the hope that it will help someone out there on these vast pipes we call the Internets.