reflex-frp/reflex

Interactive programs without callbacks or side-effects. Functional Reactive Programming (FRP) uses composable events and time-varying values to describe interactive systems as pure functions. Just like other pure functional code, functional reactive code is easier to get right on the first try, maintain, and reuse.

1,116

stars

891

commits

Haskell

primary language

Aug 29, 2026

updated

reflex-frp.org
frp
functional-reactive-programming
haskell
reactive
reflex-frp

README

Reflex

Haskell Hackage BSD3 License

Interactive programs without callbacks or side-effects. Functional Reactive Programming (FRP) uses composable events and time-varying values to describe interactive systems as pure functions. Just like other pure functional code, functional reactive code is easier to get right on the first try, maintain, and reuse.

Reflex is a fully-deterministic, higher-order Functional Reactive Programming interface and an engine that efficiently implements that interface.

Visit https://reflex-frp.org for more information, tutorials, documentation and examples.

Resources

Hacking

From the root of a Reflex Platform checkout, run ./scripts/hack-on haskell-overlays/reflex-packages/dep/reflex. This will check out the reflex source code into the haskell-overlays/reflex-packages/dep/reflex directory. You can then point that checkout at your fork, make changes, etc. Use the ./try-reflex or ./scripts/work-on scripts to start a shell in which you can test your changes.

Contributors

(top 30 of 70)

ali-abrar

183 commits

Ericson2314

159 commits

3noch

61 commits

reflex-frp/reflex

Interactive programs without callbacks or side-effects. Functional Reactive Programming (FRP) uses composable events and time-varying values to describe interactive systems as pure functions. Just like other pure functional code, functional reactive code is easier to get right on the first try, maintain, and reuse.

1,116

stars

891

commits

Haskell

primary language

Aug 29, 2026

updated

reflex-frp.org
frp
functional-reactive-programming
haskell
reactive
reflex-frp

README

Reflex

Haskell Hackage BSD3 License

Interactive programs without callbacks or side-effects. Functional Reactive Programming (FRP) uses composable events and time-varying values to describe interactive systems as pure functions. Just like other pure functional code, functional reactive code is easier to get right on the first try, maintain, and reuse.

Reflex is a fully-deterministic, higher-order Functional Reactive Programming interface and an engine that efficiently implements that interface.

Visit https://reflex-frp.org for more information, tutorials, documentation and examples.

Resources

Hacking

From the root of a Reflex Platform checkout, run ./scripts/hack-on haskell-overlays/reflex-packages/dep/reflex. This will check out the reflex source code into the haskell-overlays/reflex-packages/dep/reflex directory. You can then point that checkout at your fork, make changes, etc. Use the ./try-reflex or ./scripts/work-on scripts to start a shell in which you can test your changes.

Contributors

(top 30 of 70)

ali-abrar

183 commits

Ericson2314

159 commits

3noch

61 commits

Languages

Haskell

97.5%

C

1.3%

Nix

1.2%