dali

Tangentially related, I've written a barebones assembler for Android .apk files once (strictly speaking, the assembler is for .dex files, but it also comes with a set of tools to package and sign .apk files). It showed up to be surprisingly easy. I expected to stumble upon some blocker issue any time that would make it impossible for me to continue — but one just never materialized! It's written mainly in Nim and provides enough primitives to allow creating Java "stubs" for native .so libraries, so that .apk-s can be built in Nim WITHOUT JDK AT ALL. The Android NDK is still kinda needed/useful, though IIRC mainly for access to adb, and especially adb logcat (which you'll need A LOT for debugging if you try to use this contraption). I'd love to One Day™ Rewrite It In Rust, so that we could write .apk-s purely using the Rust toolchain, just

https://github.com/akavel/dali was one (a fully hand-written non-Java, non-JVM assembler for Android .apk files); I managed to write a rudimentary flappy-bird-like prototype in it and did a presentation about the project: https://www.youtube.com/watch?v=wr9X5NCwPlI&list=PLxLdEZg8DR... but it's on a shelf now, didn't get much attention, and I don't feel bad about that. Had some roadblocks, but managed to overcome them, and I'm honestly surprised how the core effort was basically easy to implement and how the formats were open and relatively simple. (The main real issues I had were that debugging via adb logs was tiresome when something was not working.) What was funny about this project was that I started it with basically a thought of: "there will be probably some annoying roadblock at some point that will make it unviable to continue; I

Came here to mention nim that I've followed with great interest. As it compiles to C you can probably use it just about everywhere. As far as android support this guy is working on adding support to android via Dalvik assembly. The usual approach to get nim to work with android would be JNI but that might cause problems for example with x86 android machines if I am not mistaken. https://github.com/akavel/dali

As mentioned in other comments, maybe worth to note that it's an assembler in a library form, i.e. without code for a parser. But then, looking at it in another way, it's a clever reuse of the C compiler's parser! Now, in a something of a "shameless plug", incidentally I took a very similar approach[1] recently, going for a "library form" too when writing an experimental assembler for Dalvik (i.e. Android VM) bytecode. Not having to write a parser helped me to iterate/prototype/hack faster! [1]: https://github.com/akavel/dali/blob/d79cec81293abc5f3a87f4d8...