Yet another: this is the whole compiler, but for a simpler language and target. https://github.com/darius/squeam/blob/master/eg/lambdacompil...

It's in my own Scheme variant, I'm afraid. I guess I should translate it to something people know. But, for example

    ;; Variable reference
    (to (var-ref<- v)
      (make ({.free-vars} (set<- v))
            ({.compile s k} (cons (s v) k))))

turns a source-code variable access into an AST object with two methods: 1. The free-variable set of this AST has just that one variable. 2. To compile this to bytecode, given a scope s and following code k, ask the scope what instruction to emit for this variable, and prepend that to k. (In general k is passed in for the sake of tail-call optimization, on line 33.)