Open source Tools to make the complex simple

We create and maintain Open Source libraries that fill in gaps in the app development ecosystem.

“BigTest is the testing framework I’ve always wanted to have. It takes all we’ve learned about testing and wraps it up in a coherent and powerful package.”

—Jonas Nicklas, Creator of Capybara, co-creator of BigTest

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BigTest — truly cross-browser testing made easy

BigTest’s novel architecture combines the sophistication of modern tooling, our decades-long experience writing tests, plus all the lessons learned from Capybara, Rail’s famous end-to-end testing framework.

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Effection: algebraic effects API

Over the years we’ve iterated on the ergonomics that make algebraic effects easy to use within popular javascript frameworks. This library makes it possible for us to have sophisticated concurrent threads running on BigTest.

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Microstates: composable primitives for Javascript

Microstates introduces javascript structure primitives that resemble traditional, intuitive, mutable objects. But behind the scenes everything is a pure function handling immutable data, giving you the benefits of functional programming without the mental overhead.

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@frontside/javascript: code linters and standards

Code quality necessarily comes from writing consistent code. We ensure logical and uniform coding by using common eslint rules and tsconfig setups that are available as open source packages.

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Frontmacs: a curated emacs distribution

Optimized for web workflows, our emacs distribution delights the users of this popular text editor every time. We’ve built it so it can be extensible and customizable, and we also included our favorite plugins and settings for working with javascript.

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