# What changed in jsii-rosetta

> 21 changes in jsii-rosetta 5 to 6 from its official release notes, upgrade guides and advisories: 3 breaking, 2 security, 3 new APIs and options. Each one cited. Sources checked 2026-10-29. HTML: https://unstale.sh/npm/jsii-rosetta/

To see which of these apply to a repository, run `npx @unstale/cli init` in it.

## jsii-rosetta 6

### Security

- A transitive CVE was removed. (5.9.67, 6.0.16) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v6.0.16), [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.67)

### Tooling

- Adds support for TypeScript 6.0. (6.0.0) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v6.0.0)

### Fixes and other changes

- Fixed non-compiling class renderings in the C# and Go visitors. (6.0.15) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v6.0.15)
- Corrected Java and Go names for libraries that manage their own tsconfig.json. (5.9.60, 6.0.9) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v6.0.9), [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.60)

## jsii-rosetta 5

### Breaking changes

- The minimum required Node.js version was updated. (5.9.28) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.28)
- Upgraded to Node.js 20 for xmlbuilder2 compatibility, so developers running jsii-rosetta need Node.js 20. (5.8.24) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.8.24)
- jsii-rosetta is built against TypeScript 5.0 and follows its major.minor release line, allowing developers to use newer TypeScript language features. (5.0.0) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.0.0)

### Security

- Fixes package releases so they include npm provenance attestations. (5.9.48) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.48)

### New APIs and options

- Set TIMING=1 to collect snippet extraction times. (5.8.22, 5.9.21) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.8.22), [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.21)
- A new batched extraction option improves performance by 25x. (5.8.22, 5.9.19) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.8.22), [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.19)
- Adds support for the class-covariant-overrides feature. (5.8.18, 5.9.10) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.8.18), [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.10)

### Tooling

- Debug output for type fingerprints is added. (5.8.22, 5.9.21) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.8.22), [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.21)
- Use a tilde range for the jsii-rosetta devDependency to control when upgrades introduce future TypeScript language versions. (5.0.0) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.0.0)

### Fixes and other changes

- Fixes release failures for tags on maintenance branches. (5.9.53) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.53)
- Suppresses xmldom fatalError stderr noise when processing unclosed HTML-like tags. (5.9.34) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.34)
- Corrects Python snake_case conversion for consecutive uppercase letters. (5.9.33) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.33)
- No longer fails when multiple concrete dependencies have the same version. (5.9.31) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.31)
- Snippet merging is fixed so it no longer prevents effective caching. (5.8.22, 5.9.22) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.8.22), [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.22)
- TIMING output is now printed as the very last thing. (5.9.21) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.21)
- Python synthetic imports are shown when usage is visible. (5.8.22, 5.9.19) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.8.22), [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.19)
- Logging for the translation process and worker diagnostics is improved, making those operations easier to diagnose. (5.8.22, 5.9.19) — [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.8.22), [release notes](https://github.com/aws/jsii-rosetta/releases/tag/v5.9.19)