Rust allows for cross compiling . So you might only have Linux , Mac and Windows binary builds but you can use them to build it for other archs . We have Linux ARMx 86 x 8664 mipsmipselpowerpc , Windows 32 x 64 . OSX . iOSAndroidWebasm as build targets . BSDsSolaris but maybe only on x 86 x 8664 , than again I ' m not sure if anyone has tried any others , maybe a PowerPCARM BSD works . . Having said that , other CPU architectures are limited currently . Particularly embedded , but it ' s being worked on . Rust ' s compiler toolchain is based on LLVM , so that ' s the first piece that needs support for a given chip . LLVM just had AVR support added to 4 . 0 dev this month . Rust has out of tree support currently via the rustavr fork but it is in the process of updating to the LLVM 4 . 0 dev previously it was using a patched AVRLLVM . Then it needs to get up to date with the Rust trunk and get it upstreamed . The other thing that is required is ' bare metal ' support . Basically the std library needs a OS for things like having a file system . So while we have many cpu archs via Linux , currently there is limited support without an OS . But you can write code without using std . And get nonOS ARM working . AVR should be the same although a bit harder as you need the out of tree fork . There is also a tool called xargo for helping embedded programming . PIC support seems unlikely any time soon due to a lack of LLVM backend . Xtensa also lacks a LLVM port ESP 8266 , etc . . RISCV is getting merged into LLVMdev 2016 October 105768 . html , but I haven ' t heard of any on working on a Rust port . A LinuxRISCV port would probably be fairly quick but bare metal RISCV would be in the same boat as AVRARM . There is the llvmcbecbe that would let any arch supported by a c compiler work in theory .