Dawson Chris - Building tools with GitHub: customize your workflow

by Chris Dawson and Ben Straub

Copyright 2016 Chris Dawson, Ben Straub. All rights reserved.

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• February 2016: First Edition

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978-1-491-93350-3

[LSI]

This book contains stories about building software tools.

If you write software on a daily basis, you realize the act ofwriting software is the craft of creating tools. Software is nothingmore than a tool. A spreadsheet is fundamentally a tool toadd and subtract numbers. A video game is fundamentally a tool toalleviate boredom. Almost immediately after people started writingsoftware tools we then discovered we needed more tools to permit us towrite the tools we set out to build in the first place. Letscall these tools that are strictly to support writing software (ratherthan software tools for the general population) meta-tools.

One of the most important meta-tools in the software development worldis Git. Git is a meta-tool that helps software developersmanage the complexity that comes from writing software. Git allowssoftware developers to store snapshots of their programs (and theneasily restore those snapshots if necessary) and to easily collaboratewith other programmers (a surprisingly complicated problem). Git iscalled a source code management (SCM) tool and though there were many otherSCMs before Git, Git has taken the software world by storm like noother before it and now dominates the SCM landscape.

GitHub is a company that saw the immense potential of Git early on andbuilt a layer of web services on top of the existing features foundin Git. Not surprisingly, one of the factors behind its success was thatGitHub employees embraced the ethos of writing meta-tools from thebeginning. Building meta-tools requires the courage to take a littleextra time to build a meta-tool rather thantaking the easy route to get the public-facing software out thedoor. GitHub employees are proud of this prioritization and havewritten extensively about the benefits, which include easy on-boardingof new hires and a transparent workflow visible to all employees.

This book looks at the tools GitHub uses internally. TheGitHub.com website is itself a meta-tool, and we discuss the manyfacets of the GitHub service. Specifically these technologies are theGitHub API and related GitHub technologies, Gollum wiki, Jekyllstatic page generator, and the chat robot called Hubot (if you arenot familiar with any of these, well explain them fully in theirrespective chapters).

To reiterate, this book is not a reference of those technologies. Thisbook is a story-book, a book that relates the process of buildingsoftware meta-tools, explaining not only the technology specifics, butalso the compromises, the realities of refactoring, and the challengesinherent to writing meta-tools in long narrative storyform.

Meta-tools require a different mindset than what comes frombuilding software available to the general population. Meta-tools aregenerally open source, which requires adifferent level of responsibility and usage. One could argue thatsoftware engineers are more demanding of quality than general usersbecause software developers know they can take action to improve orfork software that does not work for them. Meta-tools enforce a higherlevel of contributory involvement, which makes automated testsalmost a requirement. All of these concepts constitute the backgroundstory behind meta-tools, and we show you how they play out whenbuilding your own.