MVar data type for predictable low-level concurrency

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No dependencies. Barely 1.08KB minified and gzipped. MVar is only concerned with flow control and integrates with any state-management solution.


Runs on every JavaScript-runtime-system. Builds are available for ES6 native modules, UMD, AMD, CommonJS, and as a standalone script.


We use a combination of static type checking, property-based testing, and static code analysis to prevent bugs from sneaking into the system.

# Try it!

Here is how you would write a simple "Hello World"-a program using MVar. The call to setTimeout is only pathological to demonstrate how MVar handles asynchronous tasks. Head over to the documentation-site for a larger example.