Before I joined Segment, I was something of a Github stalker. Which is how I found Segment.

(To be clear, I’m still a Github stalker, only now I work here.)

We’ve all been there before: lost in the depths of a mental call stack, eight repos deep with only a foggy idea of why it’s 3AM and how I ended up here.

I snooped through Segment’s projects for I don’t know how long before starting to realize what drew me in so consistently across every project. And it wasn’t until I joined the team and learned the thought-process and ethos behind them that I gained a sincere appreciation for why we have over 1000 repos.

Our approach to software is radically modularpluggable and composable.

Which makes sense, because in reality, that’s the whole point of Segment.

When you build your tools at the right level of abstraction, incidental complexity is hidden away and edge-cases take care of themselves. Not to mention, you can be a lot more productive. It’s what precipitated analytics.js in our early days: the intention to find the right level of abstraction for collecting data about who your users are and what they’re doing. It’s why people love expresskoa, and reworktoo.

It’s also why we’re big proponents of the component and duo ecosystem. We even manage customer and partner logos with an extensible and modular systemand our entire front-end is built with components based on ripple and, more recently, deku.

It’s hard to communicate the power of this modular and composable approach, but it ends up being disarmingly obvious to developers and product strategists alike (see Rich Hickey’s presentation. Rather than attempt to explain it outright, I’ll give you a tour of our more popular open source repos to show you how we’ve tried to make them small, self-contained, and composable.

Let’s dive into some examples!



When building our documentationacademyblogjob board, and help section, we wanted the speed and simplicity of static sites over the restrictiveness and complexity of a CMS. And though there’s a lot of logic that could be shared between them, each called for its own unique feature-set and build process.

But when we looked at existing static site generators, they all imposed a degree of structure on the content, and weren’t flexible enough for our wide array of use cases. Enter: Metalsmith.

Metalsmith does not impose any assumptions on your content model or build process. In fact, Metalsmith is just an abstraction for manipulating a directory of files.

Breaking static sites down to their core, the underlying abstraction includes content in files (blog entries, job listings, what have you), and these files’ associated metadata. Metalsmith allows you to read a directory of files, then run a series of plugins on that data to transform it exactly the way you need.

For example, you can run markdown files through handlebars templates, create navigation or a table of contents, compress images, concatenate scripts, or anything your heart desires before writing the result to the build directory.

new Metalsmith(root)

For example, our blog articles are just files with two sections: a header with metadata about the author, date, title and url, and then markdown for the content of the article. Metalsmith transforms the markdown to HTML, wraps the posts in their layout, looks up and inserts the author’s avatar, renders any custom Handlebars helpers, etc. The beauty is that the build process is completely customizable and abstract for many use cases. It’s just a matter of which plugins you choose. And the word is out: the metalsmith plugin ecosystem is booming!

By building our static sites with Metalsmith and hosting the source on Github, our marketing, success, and business teams can create and edit posts right from the Github web interface, or work locally and “sync” their updates with Github for Mac. This workflow closely mirrors a traditional CMS, but gives us the speed and reliability of a pre-built, static site while also lending things like auto-generated code samples for every language and automatically compiled navigation, two places otherwise prone to falling out of date.



As you’ve heard, Segment is committed to a component-driven development model: breaking things into small pieces that can be developed in isolation, and then shared and reused. But when everything is a plugin, that means an awful lot of small repos. So we build tooling to make working with lots of small repos frictionless.

For example, when we or a partner want to add a new integration to Segment, the very first thing we need to do is create a new repo to house that project. In order to enforce common style across file structure and code, we built a project scaffolder that generates a “base” the developer can use to jump right into their project.

This is where Khaos comes in — our own project scaffolder that’s built on Metalsmith, the first example here of building building blocks (with building blocks :). In the source, you can see how even we tried to make Khaos itself composable and modular.

Khaos is really just a CLI wrapper for metalsmith with the following plugin pipeline:

  • Read template files from a directory.
  • Parse files for template placeholders.
  • Prompt user to fill in each placeholder.
  • Render files with a templating engine.
  • Write filled-in files to a new directory.

We have khaos templates for new logos, integrations, back-end services, nightmare plugins, etc. Not only does this make getting started easy, but it reinforces cultural values like defaulting yes to MIT licensing.



As you might guess, we use Segment as the backbone of our customer data pipeline to route our data into our third-party tools and to Amazon Redshift.

While we use our partners’ visualization tools to write and share ad-hoc queries against data in Segment SQL, we wanted to make the most important data points accessible in real time throughout the organization. So we built Metrics.

We query the underlying the data from Segment Warehouses and services like Stripe and Zendesk, and use Metrics to orchestrate these queries and store the aggregate metrics for each team. On any given team’s board you might see ARR, MRR, daily signups, the depth of our queue for new integration requests, number of active Zendesk tickets by department, number of deploys in the last week – the list goes on.

We’ll go into more details about the business motivations and outcomes around Metrics in a future blog post, but what excites me most about Metrics is how it’s designed under the hood. It’s another example of offloading feature scope to plugins.

You can use plugins to define what data gets collected and stored, the interval at which it’s updated, and where those metrics are pushed: to dashboards, spreadsheets, summary emails, or anywhere else your heart desires.

All metrics does is expose an API for orchestrating this dance via plugins.

new Metrics()
  //out of the box plugins
  .every('10m', require('metrics-stripe-charges')('apikey'))
  .every('10m', require('metrics-stripe-subscriptions')('apikey'))
  .every('1d',  require('metrics-aws-billing')(/*params*/))

  //scheduling redshift queries, storing results as Metrics
  .every('1h',  signups(redshift))
  .every('1h',  activeAccounts(redshift))
  .every('1h',  activation(redshift))
  .every('1h',  engineering(redshift))
  .every('1h',  apiCalls(redshift))
  .every('1h',  paidAccounts(redshift))

  //custom plugins
  .every('1h',  enterprise)
  .every('1h',  blog)
  .every('1h',  revenue)
  .every('15m', success(zendesk))

  //populate dashboards

Check it out on github here!



We have a bit of an obsession with automation and elimination of the mundane. And that’s what drove the development of Hermes.

Raph, our beloved head of sales and first businessperson at Segment, thought Hermes was Ian’s potty-mouthed “ami français” for a few months. Nope. Hermes is a chatbot whose sole feature is, you guessed it, a plugin interface.

When you’re building a new feature for Hermes, like looking up an account’s usage, or fetching a gif from the interwebs, all you need to do is tell Hermes what he’s listening for and what to say back. Everything in between, you define in your own plugin.

Whether we want to announce that lunch is here, check Loggly for errors related to a customer’s project, kickoff a Metalsmith build of the latest blog release, or create an SVG logo for a new integration, we get our boy Hermes Hubeau to do the dirty (repetitive) work.

We were thankful for the plugin approach when we switched from Hipchat to Slack. Instead of rewriting all of Hermes, we just hot-swapped the old plugin with the new!



“Wait a minute — your chat bot creates SVG logos?!”

Nope! Humans do. Hermes just knows how to ask politely. He creates a new logorepo with Khaos, then spins up a Nightmare instance based on Metalsmith plugins, navigates to 99designs Tasks, and posts a job. When the job is finished, he resizes the logos with our logo component creation CLI.

Automating these sorts of jobs, for which there was not yet a public API, required us to mimic and automate pointing and clicking in a web browser, and that’s what Nightmare does. While there were plenty of tools to do this, like PhantomJS, webdriver APIs imposed the burden of a convoluted interface and lots of mental overhead. So we wrote a library that puts all those headaches under the covers, and lets you automate browsers the way you browse the web:

new Nightmare()

Browser automation is nothing new, but we tried to give Nightmare a cleaner API and a plugin interface so people could more easily compose automations. The goal is to make it really simple to automate tasks on the web and create APIs where a public one doesn’t yet exist.

Check out Github for nightmare plugins like X-Ray99designsSecureapay, and LinkedIn.


We try to break things into small, reusable pieces and hate to solve the same problem twice, pushing for simple solutions that build off of each other and are flexible enough for multiple use cases.

This level of commitment to “building building blocks” and sharing them with the community is what drew me in so hypnotically to Segment in the first place, and why I feel so immensely fortunate to be here now. As a success engineer, part of my job is to build and maintain internal tooling that enables us to better serve our customers. I’m empowered to apply the same principles and rigor used by our product team and core engineers to those projects, and my development and product direction skills have improved faster than I ever thought possible as a result.

If you think of any cool use cases for any of these tools at your company, we’d love to hear more about them. Tweet us @segment with your ideas or fork away on GitHub! We always appreciate new plugins and contributions. And if any of this particularly resonates with you, we’re hiring!