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+# JIT calculator challenge implemented with ejit
+
+This is an implementation of the
+[JIT calculator challenge](https://ochagavia.nl/blog/the-jit-calculator-challenge/)
+using my [ejit](https://metanimi.dy.fi/cgit/ejit/) library in C. Possibly not
+quite what was intended with the challenge, but at least I had a nice evening.
+
+## Building
+
+This repository uses submodules, remember to run
+```
+git submodule update --init --recursive
+```
+
+To build, run
+```
+make
+```
+
+which should produce a `calc` binary. You can add compilation parameters like
+```
+make RELEASE=1 LTO=1
+```
+
+to build an optimized binary. Remember to `make clean` before you specify new
+parameters.
+
+## `ejit`
+
+`ejit` is a library that implements a bytecode interpreter for a language
+(almost) identical to the one used by the massively cool
+[lightening](https://gitlab.com/wingo/lightening) JIT library. The idea is that
+`ejit` transparently lowers all bytecode instructions to the equivalent
+`lightening` instructions, which in turn are lowered to machine code when on a
+supported machine. For machines not (yet) supported by `lightening`, the
+bytecode interpeter means that programs written with `ejit` will still function
+correctly, just a bit slower.