Translating non-trivial codebases with Claude

A developer used Claude Code (Opus 4.6) to successfully translate two non-trivial codebases — one from C++ to Java, another from Haskell to Clojure — and reports both worked "splendidly." The post focuses less on the translation itself and more on what capabilities it unlocks, framed through the author's background in NLP and a legacy Polish corpus tool called Poliqarp. A practical, first-hand experience report on agentic large-scale code migration using Claude Code.