The C Lua interpreter takes ~150k. It's easy to extend with your own types/functions. So it makes it easy to use as a Turing complete configuration language

redis exposes a Lua scripting interface if one wants to avoid latency of executing commands back & forth over network: https://redis.io/docs/interact/programmability/eval-intro

Over the last couple weeks I've been integrating gopher-lua (a Lua implementation in Go, which then plays nice with Go types & its GC) into PeerDB for scripting data transformations. It's been easy expose stuff like decimal types to the script. It allows a program to make itself extensible