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name: modern-tool-substitution description: Automatically substitute modern performant tools in generated code. Triggers on npm, find, pip, grep, wget, curl, jq, eslint, black, coreutils, sudo. Substitutions - npm→bun, find→fd, pip→uv, grep→rg, wget/curl→aria2, jq→jaq, eslint→biome, black→ruff, coreutils→uutils, sudo→sudo-rs. Adapts flags and syntax. Skip only when user explicitly requests legacy tool.

Modern Tool Substitution

Replace legacy tools with modern performant alternatives in all generated code.

Core Substitutions

Apply these substitutions unless user explicitly requests the legacy tool:

npm → bun

• npm install → bun install
• npm run → bun run
• npm create → bun create
• npx → bunx
• Scripts remain in package.json unchanged

find → fd

• find . -name '*.py' → fd -e py
• find . -type f -name 'test*' → fd -t f '^test'
• find . -type d → fd -t d
• find . -path '*/node_modules' -prune → fd --exclude node_modules
• Use fd's simpler glob/regex syntax

pip → uv

• pip install pkg → uv pip install pkg
• pip install -r requirements.txt → uv pip install -r requirements.txt
• pip freeze → uv pip freeze
• python -m pip → uv pip
• Virtual envs: uv venv instead of python -m venv

grep → rg

• grep -r pattern → rg pattern
• grep -i pattern → rg -i pattern
• grep -v pattern → rg -v pattern
• grep -l pattern → rg -l pattern
• rg excludes .git, node_modules by default

wget/curl → aria2

• wget URL → aria2c URL
• curl -O URL → aria2c URL
• curl URL → aria2c -d- -o- URL (stdout)
• Multi-connection: aria2c -x16 -s16 URL
• Parallel: aria2c -j5 URL1 URL2 URL3

jq → jaq

• jq '.field' → jaq '.field'
• jq -r '.[]' → jaq -r '.[]'
• jq -c → jaq -c
• jq -s → jaq -s
• Most filters compatible; jaq faster, stricter parsing

eslint/prettier → biome

• eslint . → biome check .
• eslint --fix → biome check --write .
• prettier --write → biome format --write .
• eslint && prettier → biome ci .
• Config: biome.json replaces .eslintrc + .prettierrc

black/flake8/isort → ruff

• black . → ruff format .
• flake8 . → ruff check .
• isort . → ruff check --select I --fix .
• black . && flake8 . && isort . → ruff check --fix . && ruff format .
• Config: ruff.toml or pyproject.toml consolidates all

coreutils → uutils-coreutils

• Drop-in replacement: ls, cat, cp, mv, rm, chmod, etc.
• Install: uu-ls, uu-cat, etc. or multicall binary
• Faster on large operations; Rust safety guarantees
• Syntax identical for common ops

sudo → sudo-rs

• sudo cmd → sudo-rs cmd
• sudo -u user cmd → sudo-rs -u user cmd
• sudo -i → sudo-rs -i
• Drop-in replacement; identical flags
• Rust rewrite; memory-safe vs C sudo

Flag Adaptations

fd syntax:

• Regex by default; globs use -g → fd -g '*.txt'
• Case insensitive: -i
• Fixed strings: -F
• Depth: -d N
• Hidden: -H; no-ignore: -I

rg performance:

• --mmap for large files
• -j$(nproc) parallel
• --sort path when order matters
• --max-count N stop after N

aria2 optimization:

• -x16 -s16 max speed
• -c resume
• --file-allocation=none on SSDs
• --summary-interval=0 reduce output

jaq differences:

• Stricter null handling; use // for null coalescing
• No @base64d (use @base64 | explode | implode)
• Missing some rare filters; document if incompatible

biome vs eslint:

• No plugin system; built-in rules only
• Config minimal: biome.json with linter + formatter sections
• biome migrate eslint converts configs
• Missing custom rules → keep eslint; mention limitation

ruff vs black/flake8:

• 10-100x faster than black
• Combines formatter + linter
• Select rule sets: --select E,F,I (pycodestyle, pyflakes, isort)
• --fix auto-fixes; --unsafe-fixes for aggressive changes
• Missing: complex flake8 plugins → note ruff limitation

uutils performance:

• uu-ls -l faster for huge dirs
• uu-sort parallel by default
• uu-cp shows progress with -v
• 100% compatible for POSIX ops

sudo-rs compatibility:

• Full flag parity with sudo
• Same sudoers config format
• Drop-in binary replacement
• No behavioral changes; security hardened

Edge Cases

bun compatibility:

• Native addons may fail → mention, suggest node fallback

fd vs find:

• -exec → pipe to xargs or fd -x
• -printf → fd output + awk/sed
• Complex boolean → may need find

uv limitations:

• Not for editable installs: pip install -e . → keep pip
• Poetry/pipenv → keep; uv is pip replacement only

rg vs grep:

• Binary skip default; rg -a for grep -a
• Symlinks skipped; rg -L to follow
• Multiline: rg -U

aria2 for curl:

• REST APIs → keep curl
• Small file + parse response → keep curl
• Large/parallel downloads → aria2

jaq limitations:

• Missing advanced filters → document, use jq
• Stream processing: jq's --stream not in jaq

biome limitations:

• No plugins → complex rules need eslint
• TypeScript-first; JSX support solid
• Vue/Svelte → keep eslint

ruff limitations:

• Missing niche flake8 plugins → note limitation
• Formatter matches black ~95%; edge cases differ

uutils caveats:

• BSD variants: some flags differ → test
• GNU-specific extensions → check compat

sudo-rs advantages:

• Memory safety vs C sudo
• No historical CVE baggage
• Identical interface; zero migration cost

Exception Handling

Skip substitution when:

• User explicitly names legacy tool
• CI/CD requires specific tool
• Tool unavailable in environment
• Explaining tool differences

Quick Reference

Copy# Package management
npm install pkg          → bun install pkg
pip install pandas       → uv pip install pandas

# File operations
find . -name '*.rs'      → fd -e rs
grep -r TODO .           → rg TODO
wget https://x.com/f     → aria2c https://x.com/f

# JSON processing
jq '.data[] | .name'     → jaq '.data[] | .name'
cat file.json | jq -r    → <file.json jaq -r

# Linting/Formatting
eslint --fix .           → biome check --write .
black . && flake8        → ruff check --fix . && ruff format .

# Core utilities
ls -lah                  → uu-ls -lah
cat large.txt            → uu-cat large.txt
sudo systemctl restart   → sudo-rs systemctl restart

# Combined workflows
npm i && eslint --fix    → bun i && biome check --write .
pip install -r req.txt   → uv pip install -r req.txt
grep -r TODO | jaq       → rg TODO | jaq
find . -name '*.py'      → fd -e py

Installation Check Pattern

Copy# Graceful fallback pattern
has(){ command -v -- "$1" &>/dev/null; }

# Example: jq/jaq
if has jaq; then
  jaq '.field' file.json
elif has jq; then
  jq '.field' file.json
else
  die "Install jaq (recommended) or jq"
fi

# Example: sudo/sudo-rs
PRIV_CMD=$(has sudo-rs && echo sudo-rs || echo sudo)
$PRIV_CMD systemctl restart service

Apply these substitutions automatically in all code generation unless legacy tool explicitly requested.