What's Changed
Tombi v1.5.0 is a major performance and architecture release.
We redesigned the parser and AST around a compact, source-backed syntax tape, replacing the previous red-green syntax tree.
The new architecture is optimized for Tombi’s lossless, long-lived editor and LSP workloads: it improves memory locality and reduces allocation and pointer-chasing overhead while preserving comments, punctuation, incomplete syntax, and diagnostics.
The AST and document-tree interfaces are now also separated from their syntax-backed implementations.
We also optimized hot paths throughout the parser, JSON Schema processing, linter, formatter, and stdin-based CLI workflows.
In our Apple M2 Max benchmarks, long ASCII comment lexing was approximately 2.3× faster, selected JSON parsing workloads improved by up to 84%, and repository-wide lint time decreased from approximately 355 ms to 81 ms.
🚨 Breaking Changes
🐝 Bug Fixes
🛠️ Other Changes
- Improve minimal-change guidance for agents by @ya7010 in #2137
- perf(parser): accelerate long comment scanning by @ya7010 in #2141
- perf: speed up lint and format by @ya7010 in #2142
- perf: reduce stdin runtime overhead by @ya7010 in #2143
- perf(json): accelerate long string parsing by @ya7010 in #2145
- perf(json): optimize lexer and parser hot paths by @ya7010 in #2146
Full Changelog: v1.4.1...v1.5.0
