CLI Flags

Complete reference for all typemux-cc command-line flags

All CLI flags can be set via environment variables. CLI flags take precedence over environment variables.

Core Flags

--log-file · path

Path to log file for debug output.

When specified, logs are written to both stderr (default) and the specified file.

Environment variable: TYPEMUX_CC_LOG_FILE

Default: Not set (stderr only)

Example:

typemux-cc --log-file /tmp/typemux-cc.log

--max-backends · integer · default: "8"

Maximum number of concurrent LSP backend processes.

The proxy maintains a pool of backends (one per .venv). When the pool reaches this limit, the least recently used backend is evicted to make room for new ones.

Environment variable: TYPEMUX_CC_MAX_BACKENDS

Valid range: Minimum 1, no upper limit

Default: 8

Example:

# Allow up to 16 concurrent backends for large monorepos
typemux-cc --max-backends 16

--backend-ttl · integer · default: "1800"

Backend time-to-live (TTL) in seconds.

Idle backends are automatically evicted after this timeout to free memory. Set to 0 to disable TTL eviction (backends only evicted via LRU when pool is full).

Environment variable: TYPEMUX_CC_BACKEND_TTL

Default: 1800 (30 minutes)

Example:

# Keep backends alive for 1 hour
typemux-cc --backend-ttl 3600

# Disable TTL eviction entirely
typemux-cc --backend-ttl 0

--backend · enum · default: "pyright"

LSP backend type to use for Python type checking.

Environment variable: TYPEMUX_CC_BACKEND

Valid values:

• pyright - Microsoft’s Pyright type checker (default)
• ty - Google’s ty type checker
• pyrefly - Astral’s pyrefly type checker

Default: pyright

Example:

# Use ty instead of pyright
typemux-cc --backend ty

Usage Examples

Basic Usage

# Run with defaults (pyright, 8 max backends, 30min TTL)
typemux-cc

Enable Logging

# Log to file for debugging
typemux-cc --log-file /tmp/typemux-cc.log

Large Monorepo Configuration

# More backends, longer TTL, with logging
typemux-cc \
  --max-backends 20 \
  --backend-ttl 7200 \
  --log-file /var/log/typemux-cc.log

Use Alternative Backend

# Use ty backend instead of pyright
typemux-cc --backend ty

Combine Multiple Flags

# Complete configuration example
typemux-cc \
  --backend ty \
  --max-backends 12 \
  --backend-ttl 3600 \
  --log-file ~/.local/state/typemux-cc.log

Flag Precedence

When both CLI flags and environment variables are set:

1. CLI flags take precedence over environment variables
2. Environment variables are used if no CLI flag is provided
3. Default values are used if neither is set

Example:

# CLI flag wins (uses ty, not pyright)
export TYPEMUX_CC_BACKEND=pyright
typemux-cc --backend ty  # Uses ty

See Also

• Environment Variables - Alternative configuration method
• Configuration - Detailed configuration strategies
• Architecture - Backend pool management details