dtsong Library Evaluation
Purpose
Produce a structured, weighted comparison of candidate libraries to make dependency decisions based on evidence rather than familiarity or hype.
Inputs
- The need or problem the library should solve
- Any known candidates (or let the process discover them)
- Project constraints (bundle size budget, license requirements, framework compatibility)
- Current tech stack and existing dependencies
Process
Step 1: Identify Candidate Libraries
- Search npm, GitHub, and community recommendations for the problem space
- Include the most popular option, the most recently trending option, and at least one lightweight alternative
- Note any candidates already in use in the codebase's dependency tree
Step 2: Evaluate Popularity Metrics
For each candidate:
- npm weekly downloads (absolute number and trend direction)
- GitHub stars and recent star velocity
- Community size (Discord, Stack Overflow tags, GitHub Discussions activity)
- Notable adopters (large companies or well-known projects using it)
Step 3: Assess Maintenance Health
For each candidate:
- Commit frequency: Active development or maintenance-only?
- Issue response time: Median time to first response on new issues
- Release cadence: Regular releases or long gaps?
- Bus factor: Single maintainer or team? Corporate backing?
- Breaking change history: How are major versions handled?
Step 4: Measure Bundle Impact
For each candidate:
- Gzipped bundle size (via bundlephobia or similar)
- Tree-shaking support (ESM exports, side-effect-free)
- Dependency count (transitive dependencies and their health)
- Runtime performance characteristics if applicable
Step 5: Review API Quality and Developer Experience
For each candidate:
- TypeScript support (built-in types, DefinitelyTyped, quality of types)
- Documentation quality (getting started guide, API reference, examples)
- API ergonomics (intuitive naming, sensible defaults, composability)
- Migration path from current solution if applicable
Step 6: Check License Compatibility
For each candidate:
- License type (MIT, Apache 2.0, ISC, GPL, etc.)
- Compatibility with project's license
- Transitive dependency license concerns
- Any commercial use restrictions
Step 7: Produce Weighted Comparison Score
- Assign weights based on project priorities (e.g., bundle size matters more for client-side)
- Score each criterion 1-5
- Calculate weighted total
- Flag any deal-breakers that override the score
Output Format
Library Comparison Matrix
| Criterion | Weight | Candidate A | Candidate B | Candidate C |
|---|---|---|---|---|
| Weekly downloads | ... | .../5 | .../5 | .../5 |
| Maintenance health | ... | .../5 | .../5 | .../5 |
| Bundle size | ... | .../5 | .../5 | .../5 |
| TypeScript support | ... | .../5 | .../5 | .../5 |
| API quality | ... | .../5 | .../5 | .../5 |
| License | ... | .../5 | .../5 | .../5 |
| Weighted Total | ... | ... | ... |
Recommendation
Recommended: [Library Name] Rationale: [2-3 sentence justification referencing the top differentiating factors] Risks: [Known risks or caveats with the recommendation] Migration notes: [If replacing an existing dependency, key migration steps]
Quality Checks
- At least 3 candidate libraries evaluated
- npm download trends checked (not just absolute numbers)
- Maintenance health assessed (commit frequency, issue response, bus factor)
- Bundle size measured with gzipped numbers
- TypeScript support quality verified
- License compatibility confirmed
- Weighted scores reflect project-specific priorities
- Deal-breakers explicitly called out