langshift

Overview

Translating one file with an LLM is a demo. Translating a repository is an engineering problem: dependency manifests have to map across ecosystems, files too large for a context window have to be split without cutting a function in half, rate limits have to be survived rather than crashed on, and a run that dies at file 200 should not start over. langshift handles each of those explicitly. Its most useful design decision is the offline provider — a rule-based transformer with no LLM at all — which lets the entire test suite and CI run deterministically with no API key and no network.

Highlights

• 13 languages, with dependency manifests translated across ecosystems (package.json to requirements.txt and back)
• Oversized files split at blank-line boundaries so no chunk cuts a function body in half
• Failures feed the error back as context and retry, bounded per provider
• Checkpoint and resume: a run that stops at file 200 restarts from file 200
• A rule-based offline provider keeps CI deterministic with no API key, behind a 92% coverage gate