There are several projects for verifying quality and correctness in Clojure code bases. When surveying how they’ll work on a distributed Clojure server built for Heroku & Postgres, I took some notes on the issues that came up. These notes represent the current state of things, as well as how we, the Clojure community, can help move them forward.
Two years ago, I wrote about my first impression of NixOS, as I was using it in my workstation. While I adored the concept of declarative OS configuration, it didn’t quite fit the workflow I had in mind for my laptop. The post was concluded with me considering NixOS for my VPS, but I didn’t quite want to move away from DigitalOcean, which has support for only a few distros. What follows details how I’ve been running NixOS since, what it took, and what I’ve learned.
Orchestra is a Clojure library made as a
drop-in replacement for
clojure.spec.test.alpha, which provides custom
instrumentation that validates all aspects of function specs. Now, it also works
with ClojureScript. This post covers some pitfalls of porting Clojure projects
to ClojureScript, as well as some instruction for those looking to do so while
maintaining a respectable amount of sanity.
Clojure 1.9 has introduced a novel library, clojure.spec, which allows developers to parse and validate data using a predicative API which is just composed of Clojure functions. If there’s one thing Clojure’s good at, though there’s not just one, it’s the pure transformation of data. With spec, that grasp is broadened to allow for exceedingly expressive validation of data as well. What’s most important is that Clojure developers understand this new tool and use it to improve the safety and readability of their code.
RainLoop is a web-based MUA similar to Roundcube, Mailpile, and the like. When looking to setup portable email access for my wife, who no longer is happy with just Thunderbird, RainLoop seemed like a reasonable choice. Here are some integration notes, as well as a review and some ranting, based on my afternoon setting it up.
I recently published a C++14 value category cheat-sheet, which was created to accompany a tech talk I gave at work. For the most part, examples on prvalues and lvalues were understood with minimal confusion. However, xvalues presented the biggest hurdle for existing C++ programmers. I’d like to explore, in greater detail, why C++11 introduced xvalues and how they are essential to safe and efficient programming in modern C++.
Finding a reasonably-priced apartment in the Bay Area can be a stressful job. After factoring in the pressure of an expiring lease, making a poor decision can be even easier. One approach to weeding out the influx of duplicated, spammy, and unwanted postings is to use a bot and a set of filters. Such a bot could crawl various apartment listing sites, match all listings against your filters, and report to you in whichever format you prefer: email, HipChat, IRC, RSS, etc. Such a bot may look something like this.
I want to tackle an issue which seems prevalent in the modern software engineering industry. The idea, laid down by Steve Jobs, is that “real artists ship” and everyone else is forgotten. What does it mean to be a “real artist,” and what does it mean to “ship” as one? Unfortunately, it’s become a facade, analogous to YOLO, intended to cover one’s tracks of poor engineering practices, lack of tooling, and lack of concern for the success of the product beyond delivery.
For those building Clojure applications backed by tests, you may be wondering just how broad, or deep, your test coverage is. Fortunately, automated coverage analysis can be integrated in a handful of minutes using cloverage and codecov.
Those in Emacs land need not worry about excellent Lisp and REPL support. Here in Vim land, however, the ground is less certain. There have been a myriad of attempts to provide Paredit-like editing and SLIME-like evaluating to those who edit modally. Here’s a contemporary look at helping Vim provide the expected slurpage, barfage, evaluation, and more.
weechat is a curses-based IRC client and a very sane alternative to irssi. For those with IRC bouncers, or those who spend a great deal of time on IRC, popular channels can start to accrue rather large logs. By default, those logs are quite verbose and are never rotated. In my case, weechat’s logs were taking up 2GB worth of disk space on my VPS.
In situations where JSON’s convenient, human-readable syntax results in noticeably slower parse times and/or increased memory usage, one might look for the more compact BSON. Aside from sitting smaller in memory, BSON libraries can more easily provide non-owning solutions, which allow them to reference a read-only chunk of BSON data directly, rather than own a copy internally. This has the big selling point of allowing memory-mapped files to be used as a BSON backend, while all operations on the immutable BSON require no copying or ownership. Unfortunately, there exists an under-documented design flaw in BSON which renders it incompatible with common, standard JSON.
Clojure excels at pure transformations of persistent data. One area well-suited for this is a stateless server which transforms data between the client and the datastore. For distributed server development in Clojure, we already have Onyx, as well as wrappers for Mesos and others. An apparently less-explored option is the use of Clojure on Google App Engine, which runs sandboxed applications in Google-managed data centers while providing automatic scaling.
Higher order functions in Clojure get a great deal of attention, and for good reason. Clojure has a rich standard library of functions which focus on purely transforming data. To those studying Clojure, the for macro for list comprehension may stand out as verbose and awkward; it may also go entirely unnoticed.
On a typical GNU/Linux install, you won’t have disk encryption. Though you’re a keen user and you’ve chosen a very strong passphrase, your data is still stored openly. Should anyone steal, confiscate, buy, or otherwise obtain your hard drive, every bit of data is going to be readable. Should anyone boot into a live CD on your system and mount your drives, your data is readily available and your strong passphrase is none the wiser.
With the rise of per-website encryption, and the ease at which it now comes, we begin to expect new sites, and popular sites, to adopt this added security. But what does it buy us? Don’t be misled into thinking your browsing is private.
Anyone can make a Git commit using any name and any email address. What prevents someone from using my name and my email to contribute a malicious commit, or even simply a commit no representative of me?
With the rise of free encryption through Let’s
Encrypt, and the weight of global surveillance on our
minds, adopting HTTPS is now more important than ever. Github now allows
unforced HTTPS for its
username.github.io domains, but that coverage doesn’t
carry over to those using custom domains. The approach I’m using for this blog
and my home page, by way of reverse proxy, is documented
ClojureScript uses the Google Closure compiler, which not only mangles and minifies code, it also inlines functions and removes dead code. Still, every extra KB in your application is distributed to every client who wants to use it. So how can we make it even smaller?
For the past decade, Unity3D has lacked official GNU/Linux support. Some tenacious users have worked around this with WINE, with varying degrees of success. Fortunately for us GNU/Linux users, Unity3D is now officially available and support is provided in the new Linux forums. To improve the situation further, Arcadia is also compatible with this new GNU/Linux build. I’ll cover here how to get things up and running.
Vim-Qt is a gVim replacement which aims to address a number of graphical issues in the standard GTK-based Vim. After having used the default gVim for years, and putting up a number of its quirks, I decided to give Vim-Qt a run for its money. In short, I was pleasantly surprised.
NixOS is a novel GNU/Linux distribution started in 2003; it’s built upon the Nix package manger which provides a functional, declarative approach to package management. NixOS takes the direction of Nix, which can run on any Unix-like distro (including OS X), and continues further to allow control over the entire OS, from the file system to various services like SSH and HTTP, using the same declarative syntax. This means an entire NixOS setup, including all services, packages installed, and even configurations, can be represented in Nix configuration files and, potentially, stored some place like Github.
As I’ve covered in a previous post, I’m a passionate Vim user; maybe a little obsessive at times (my configs). Setting my love for Vim aside, Emacs, being Vim’s life-long nemesis, presents some interesting benefits. I took a week, this month, to use Emacs exclusively in my work (including C++14, Clojure, and Common Lisp) in order to weigh its benefits. Here’s what I found.
When looking to make full-stack web applications in lisp, Common Lisp and Parenscript are just as capable as Clojure and Clojurescript, if only less documented. As I wanted to make a web-based REPL for jank, my statically-typed functional programming language, I evaluated both the Clojure and Common Lisp stacks and, ultimately, decided on Common Lisp.
The popular vim text editor is known for its modal editing, intricate key sequences, and powerful capabilities and extensibility. Vim-style editing and navigation is incorporated deeply into my computing experience, covering:
Package management in Slackware (14.1, currently) has a reputation for being rather manual. The official packages are distributed as binaries, with the source included, and can typically be manipulated using the
slackpkg tool exclusively. SBo provides hundreds of unofficial packages, ranging from games, to multimedia players, to desktop environments.
My Slackware setup is unique, since, unlike most Slackers, I’ve compiled my entire OS from source. I require the latest GCC 5.1, for work with C++14, the latest Vim, for use with color_coded, and the ABI incompatibilities that follow have led me down a winding path.