@kongyo2/similarity-ts review
A focused, self-hosted CLI for TypeScript clone checks and CI gates.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
@kongyo2/similarity-ts is an open-source TypeScript code-similarity CLI and library for finding duplicate or structurally similar code. It is aimed at teams maintaining TypeScript repositories, especially those that want clone detection as part of refactoring or code-quality workflows. The tool compares functions, types, and classes through AST-based tree edit distance scoring rather than relying only on text matching. It is free to use, self-hosted, and distributed for local use through npm.
Its strongest fit is configurable repository scanning. Teams can set similarity thresholds, minimum line or token requirements, and restrictions for same-file or cross-file comparisons. TypeScript and related file-extension filters help narrow the scan, while glob-based exclusions can keep generated or intentionally repeated code out of results. Pretty and JSON output formats support both human review and automation, and CI gating can fail a workflow when duplicate code is detected.
This focus makes the package a practical choice for TypeScript teams that want a lightweight, repository-level clone gate without a hosted service or paid tier structure. It is less suitable for buyers seeking IDE integration, a broad multi-language platform, or a managed onboarding experience. The published package metadata identifies version 0.6.0, while the latest README content describes additional accuracy work associated with 0.7.0, so teams should review the package and repository state before standardizing on a version. Choose it when AST-based checks and local control matter more than ecosystem breadth.
@kongyo2/similarity-ts pros and cons
- Where it wins
- AST scoring compares functions, types, and classes structurally
- Thresholds, exclusions, and scan-scope rules support tailored checks
- JSON output and CI failure gating fit automated quality workflows
- Where it doesn't
- Focused on TypeScript and related file extensions
- No IDE integration is specified
- Self-hosted CLI workflows require local setup and maintenance
@kongyo2/similarity-ts fact sheet, pricing and score →
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