A Developer Rewrote 65,000 Lines of Go Into 60,000 Lines of Rust With Fable for $400, and the Trick Was Not Translating Directly
Rather than line-by-line translation, the author of the Rune text editor extracted the Go source into intermediate representations (hierarchical state machines, graphs, ontologies) and generated Rust from those, at $400 for the base rewrite and about $650 including tree-sitter and syntax highlighters. Verification was fuzzing plus differential testing via terminal sequence playback and Playwright screenshot comparison, not a traditional test suite, which is the main thing HN commenters attacked: "a 65k lines you didn't actually read. How did you confirm the semantic equivalence?" One commenter contrasted a direct Bun rewrite at $165,000 for 500 KLoC, making the intermediate-representation route look roughly an order of magnitude cheaper per line.
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