lazyboy: An EDSL for programming the Game Boy.

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An EDSL for programming the Nintendo Game Boy.

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Dependenciesaeson (>= && <1.5), base (>=4.7 && <5), hspec (>=2.6.1 && <2.7), microstache (>= && <1.1), text (>= && <1.3), transformers (>= && <0.6) [details]
Copyright2019 Rose
CategoryDSL, Compiler
Home page
Bug tracker
Source repositoryhead: git clone
UploadedTue Jun 4 01:40:34 UTC 2019 by rose




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Readme for lazyboy-

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LAZYBOY Build Status Coverage Status


An embedded domain-specific language + compiler written in Haskell for producing code to run on the Nintendo Game Boy.

Also features a library for manipulating constructs such as memory and graphics.

Currently, RGBASM is the only output target, but in the future native machine code generation is planned.

Syntax example (will be updated as more complex constructs are added):

main :: IO ()
main = rom >>= T.putStrLn
    where rom = compileROM $ do
            byte A 0xDE
            byte B 0xDE
            if' ((A == (0xDE :: Word8)) && (A == B)) $ do
                write (Address wram0) 0xDE

See app/Main.hs for a full usage example.

Build a ROM (output will be named

stack run > examples/main.asm
cd examples && make NAME=main

About issues

I mostly use the issue tracker on here as a place to write about planned features and compiler development, don't take the count as an indicator of active bugs, and be sure to filter to show only issues that are bugs if you are curious on the state of the project.


Please see the Contributing page on the Wiki.

Additional information about the project can also be found on the Wiki.

Special thanks

Thanks to Francesco149 and Bonzi for kindly devoting their time and knowledge to the project. The graphics functionality in particular would not be where it is without their assistance.