ELI5: Watchman – Awaiting Modifications to Construct Sooner
In this post, we’re talking about a project called Watchman, which is a file monitoring service. If you’d like to see a video about Watchman, visit the YouTube Open Source YouTube Channel.
Watchman is a file monitoring service with clients for a command line, NodeJS, and more. It records all changes and triggers assigned actions. In the example with the Facebook app, Watchman would have ensured that only files that are changed or influenced by our developers are updated. We previously shared how this service reduced build time by 60% in some cases!
Beyond the build system, Watchman has been updated to support other use cases. It can log changes, trigger test-suites, transform files and much more. Watchman has also been updated to support a wide variety of operating systems, including Windows.
Where is it used?
Watchman was first made available as an open source version by Facebook in 2013. Since then, Watchman has been used daily by our developers on Facebook. It has also been incorporated into many other open source projects such as React Native and Buck.
Where can i learn more?
To learn more about Watchman, visit their website. The project has an excellent starter and extensive documentation. The project has an active community chat on Freenode and StackOverflow. If you run into a problem, there is also a troubleshooting page on the project website.
If you have any thoughts or questions about Watchman, please let us know on our YouTube channel or tweet us at.
About the ELI5 series
In a series of short videos (around 1 minute long) one of our developer attorneys on the Facebook Open Source team explains a Facebook Open Source project in a way that is easy to understand and use.
For each of these videos we are writing an accompanying blog post (like the one you are reading right now), which you can find on our YouTube channel.
To learn more about Facebook Open Source, visit our Open Source website, subscribe to our YouTube channel, or follow us on Twitter and Facebook.
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