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ts-memory-baseline

Testing & Quality
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Measure and compare TypeScript memory usage for @regle/core and test typechecks. Use when checking TS server pressure, type-level perf regressions, or before/after heavy generic typing changes.

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How to use this skill

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Source SKILL.md: https://github.com/victorgarciaesgi/regle/blob/HEAD/.cursor/skills/ts-memory-baseline/SKILL.md

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TypeScript memory baseline procedure

This skill defines a reproducible process to measure TypeScript memory usage in this repository.

Hard requirements

  1. Use Node 24 for all measurements.
  2. Run pnpm build before any test-related measurement.
  3. pnpm run test:typecheck should never fail. If it fails, treat the run as invalid for regression tracking.

Environment setup

PATH="/Users/victorgarcia/.nvm/versions/node/v24.15.0/bin:$PATH"
node -v
pnpm -v

Expected:

  • Node v24.x
  • pnpm 11.6.0 (or project-compatible version)

Measurement runbook (must follow)

  1. Ensure no extra monorepo tasks are running.
  2. Use the exact Node 24 PATH prefix in every command.
  3. Run one warm-up pass that is discarded.
  4. Run 3 measured passes and compare medians.
  5. Save only the final medians in tests/TS_MEMORY_BASELINE_RESULTS.md.

Measurement commands

A. @regle/core compiler diagnostics

PATH="/Users/victorgarcia/.nvm/versions/node/v24.15.0/bin:$PATH" \
./node_modules/.bin/tsc -p "packages/core/tsconfig.json" --noEmit --extendedDiagnostics

Capture:

  • Memory used
  • Instantiations
  • Check time

B. Full type tests memory

Run build first:

PATH="/Users/victorgarcia/.nvm/versions/node/v24.15.0/bin:$PATH" pnpm build

Then:

PATH="/Users/victorgarcia/.nvm/versions/node/v24.15.0/bin:$PATH" \
/usr/bin/time -l pnpm run test:typecheck

Capture:

  • exit code (must be 0)
  • maximum resident set size
  • peak memory footprint
  • real/user/sys

Recommended sequence:

# warm-up (discard)
PATH="/Users/victorgarcia/.nvm/versions/node/v24.15.0/bin:$PATH" \
/usr/bin/time -l corepack pnpm run test:typecheck

# measured runs (collect all 3)
PATH="/Users/victorgarcia/.nvm/versions/node/v24.15.0/bin:$PATH" \
/usr/bin/time -l corepack pnpm run test:typecheck
PATH="/Users/victorgarcia/.nvm/versions/node/v24.15.0/bin:$PATH" \
/usr/bin/time -l corepack pnpm run test:typecheck
PATH="/Users/victorgarcia/.nvm/versions/node/v24.15.0/bin:$PATH" \
/usr/bin/time -l corepack pnpm run test:typecheck

Comparison protocol

Use median deltas because absolute values can vary with machine/CPU load.

  1. Compute medians for old baseline and new run.
  2. Compute delta % = (new - old) / old * 100.
  3. Evaluate with these thresholds:
    • Likely noise: within ±5% for memory metrics.
    • Watch zone: >5% and <=10% increase.
    • Regression candidate: >10% increase.
  4. For Check time and real time, treat as noisy:
    • investigate only if increase is >15% and reproducible across runs.
  5. If pnpm run test:typecheck exit code is non-zero, invalidate the run (do not update baseline).

Results storage

Store only numeric outcomes in:

  • tests/TS_MEMORY_BASELINE_RESULTS.md

Do not put procedural instructions in the results file.