taskmux 0.2.7

Modern tmux-based task manager for LLM development tools

Taskmux

A modern tmux session manager for LLM development tools with health monitoring, auto-restart, and WebSocket API.

Why Taskmux?

LLM coding tools like Claude Code and Cursor struggle with background tasks. Taskmux provides an LLM-friendly CLI for managing multiple background processes — restarting, checking status, reading logs — all from within your AI coding environment.

Installation

Prerequisites

• tmux
• uv (Python 3.11+)

Install

# Recommended (global install)
uv tool install taskmux

# From source
git clone https://github.com/nc9/taskmux
cd taskmux
uv tool install .

Quick Start

# Initialize in your project (creates taskmux.toml, injects agent context)
taskmux init

# Add tasks
taskmux add server "npm run dev"
taskmux add build "npm run build:watch"
taskmux add db "docker compose up postgres"

# Start all auto_start tasks
taskmux start

# Check status
taskmux status

Or create a taskmux.toml manually:

name = "myproject"

[hooks]
before_start = "echo starting stack"
after_stop = "echo stack stopped"

[tasks.server]
command = "npm run dev"

[tasks.server.hooks]
before_start = "npm run build"

[tasks.build]
command = "npm run build:watch"

[tasks.test]
command = "npm run test:watch"

[tasks.db]
command = "docker compose up postgres"
auto_start = false

Full Example

A full-stack app with a database, API server, and frontend — using health checks to ensure each service is ready before starting its dependents:

name = "fullstack-app"

[tasks.db]
command = "docker compose up postgres redis"
health_check = "pg_isready -h localhost -p 5432"
health_interval = 3

[tasks.migrate]
command = "python manage.py migrate && echo 'done' && sleep infinity"
cwd = "apps/api"
depends_on = ["db"]
health_check = "test -f .migrate-complete"

[tasks.api]
command = "python manage.py runserver 0.0.0.0:8000"
cwd = "apps/api"
port = 8000
depends_on = ["migrate"]
health_check = "curl -sf http://localhost:8000/health"
stop_grace_period = 10

[tasks.worker]
command = "celery -A myapp worker -l info"
cwd = "apps/api"
depends_on = ["db"]
max_restarts = 3
restart_backoff = 3.0

[tasks.web]
command = "bun dev"
cwd = "apps/web"
port = 3000
depends_on = ["api"]
health_check = "curl -sf http://localhost:3000"

[tasks.storybook]
command = "bun storybook"
cwd = "apps/web"
auto_start = false

What happens on taskmux start:

1. db starts first (no dependencies)
2. migrate and worker wait for db's health check (pg_isready) to pass
3. api waits for migrate's health check
4. web waits for api's health check (curl localhost:8000/health)
5. storybook is skipped (auto_start = false) — start it manually with taskmux start storybook

taskmux start                    # Starts everything in dependency order
taskmux logs                     # Interleaved logs from all tasks
taskmux logs -g "ERROR"          # Grep all tasks for errors
taskmux logs api                 # Logs from just the API
taskmux logs -f api              # Follow API logs live
taskmux health                   # Health check table
taskmux inspect api              # JSON state for a single task
taskmux restart worker           # Restart just the worker
taskmux start storybook          # Start a manual task

Commands

# Session
taskmux start                    # Start all auto_start tasks
taskmux start <task>             # Start a single task
taskmux stop                     # Stop all tasks (C-c → SIGTERM → SIGKILL)
taskmux stop <task>              # Stop a single task (signal escalation)
taskmux restart                  # Restart all tasks
taskmux restart <task>           # Restart a single task
taskmux status                   # Show session status
taskmux list                     # List tasks with health indicators

# Tasks
taskmux kill <task>              # Hard-kill a task (destroys window)
taskmux add <task> "<command>"   # Add task to config
taskmux remove <task>            # Remove task from config
taskmux inspect <task>           # JSON task state (pid, command, health)

# Logs
taskmux logs                     # Interleaved logs from all tasks
taskmux logs <task>              # Show recent logs for a task
taskmux logs -f                  # Attach to session (switch windows with tmux keybinds)
taskmux logs -f <task>           # Follow a task's logs live
taskmux logs -n 200 <task>       # Last N lines
taskmux logs -g "error"          # Search all tasks
taskmux logs <task> -g "error"   # Search one task
taskmux logs <task> -g "error" -C 5  # Grep with context lines

# Init
taskmux init                     # Interactive project setup
taskmux init --defaults          # Non-interactive, use defaults

# Monitoring
taskmux health                   # Health check table
taskmux watch                    # Watch config for changes, reload on edit
taskmux daemon --port 8765       # Run with WebSocket API + auto-restart

stop vs kill

• stop sends C-c, then escalates to SIGTERM → SIGKILL if the process doesn't exit within the grace period. Window stays alive so you can see exit output.
• kill kills the process group and destroys the window immediately.

Configuration

Format

Config file is taskmux.toml in the current directory:

name = "session-name"
auto_start = true       # global toggle, default true

[hooks]
before_start = "echo starting"
after_stop = "echo done"

[tasks.server]
command = "python manage.py runserver"
cwd = "apps/api"
port = 8000
health_check = "curl -sf http://localhost:8000/health"
stop_grace_period = 10
depends_on = ["db"]

[tasks.server.hooks]
before_start = "python manage.py migrate"

[tasks.db]
command = "docker compose up postgres"
health_check = "pg_isready -h localhost"

[tasks.worker]
command = "celery worker -A myapp"
depends_on = ["db"]
max_restarts = 3

[tasks.tailwind]
command = "npx tailwindcss -w"
auto_start = false

Fields

Field	Default	Description
name	"taskmux"	tmux session name
auto_start	true	Global toggle — if false, start creates session but launches nothing
hooks.before_start	—	Run before starting tasks
hooks.after_start	—	Run after starting tasks
hooks.before_stop	—	Run before stopping tasks
hooks.after_stop	—	Run after stopping tasks
tasks.<name>.command	—	Shell command to run
tasks.<name>.auto_start	true	Start with taskmux start
tasks.<name>.cwd	—	Working directory for the task
tasks.<name>.port	—	Port to clean up before starting (kills orphaned listeners)
tasks.<name>.health_check	—	Shell command to check health (exit 0 = healthy)
tasks.<name>.health_interval	10	Seconds between health checks
tasks.<name>.health_timeout	5	Seconds before health check times out
tasks.<name>.health_retries	3	Consecutive failures before "unhealthy"
tasks.<name>.stop_grace_period	5	Seconds to wait after C-c before escalating to SIGTERM
tasks.<name>.max_restarts	5	Max auto-restarts in daemon mode before giving up (0 = unlimited)
tasks.<name>.restart_backoff	2.0	Multiplier for restart delay (1s, 2s, 4s, 8s… capped at 60s)
tasks.<name>.depends_on	[]	Task names that must be healthy before this task starts
tasks.<name>.hooks.*	—	Per-task lifecycle hooks (same fields as global)

Dependency Ordering

Tasks with depends_on are started in topological order. Before starting a task, taskmux waits for each dependency's health check to pass (up to health_retries * health_interval seconds). If a dependency never becomes healthy, the dependent task is skipped with a warning.

Circular dependencies and references to nonexistent tasks are rejected at config load time.

When starting a single task with taskmux start <task>, dependencies are not auto-started — you get a warning if they aren't running.

Health Checks

If health_check is set, taskmux runs it as a shell command. Exit code 0 means healthy. If not set, taskmux falls back to checking if the tmux pane has a running process (not just a shell prompt).

Health checks are used by:

• taskmux health — shows a table of all task health
• taskmux start — waits for dependencies to be healthy before starting dependents
• taskmux daemon — continuously monitors and auto-restarts unhealthy tasks

Hook Cascade

Hooks fire in this order:

1. Start: global before_start → task before_start → run command → task after_start → global after_start
2. Stop: global before_stop → task before_stop → send C-c → task after_stop → global after_stop

If a before_* hook fails (non-zero exit), the action is aborted.

Process Lifecycle

Taskmux ensures processes are fully stopped before restarting and that orphaned port listeners don't block new starts.

Stop escalation (stop, restart):

1. C-c (SIGINT) — waits stop_grace_period seconds (default 5)
2. SIGTERM to process group — waits 3 seconds
3. SIGKILL to process group — force kill

Port cleanup (start, restart): If port is configured, taskmux kills any process listening on that port before starting. This handles orphaned processes from crashed sessions.

Auto-restart backoff (daemon mode): When a task keeps crashing, restart delays increase exponentially (restart_backoff multiplier, capped at 60s). After max_restarts failures, the task is left stopped. The counter resets after 60 seconds of healthy uptime.

Init & Agent Context

taskmux init bootstraps your project:

1. Creates taskmux.toml with session name (defaults to directory name)
2. Detects installed AI coding agents (Claude, Codex, OpenCode)
3. Injects taskmux usage instructions into agent context files:
   • Claude: .claude/rules/taskmux.md
   • Codex/OpenCode: AGENTS.md

Use --defaults to skip prompts (CI/automation).

Inspect

taskmux inspect <task> returns JSON with task state:

{
  "name": "api",
  "command": "python manage.py runserver 0.0.0.0:8000",
  "auto_start": true,
  "cwd": "apps/api",
  "health_check": "curl -sf http://localhost:8000/health",
  "depends_on": ["db"],
  "running": true,
  "healthy": true,
  "pid": "12345",
  "pane_current_command": "python",
  "pane_current_path": "/home/user/project/apps/api",
  "window_id": "@1",
  "pane_id": "%1"
}

Daemon Mode

Run as a background daemon with WebSocket API and auto-restart with exponential backoff:

taskmux daemon              # Default port 8765
taskmux daemon --port 9000  # Custom port

The daemon monitors task health every 30 seconds. Unhealthy tasks are restarted with exponential backoff (controlled by restart_backoff and max_restarts). Tasks that stay healthy for 60+ seconds have their restart counter reset.

WebSocket API:

const ws = new WebSocket('ws://localhost:8765');

ws.send(JSON.stringify({ command: "status" }));
ws.send(JSON.stringify({ command: "restart", params: { task: "server" } }));
ws.send(JSON.stringify({ command: "logs", params: { task: "server", lines: 50 } }));

Tmux Integration

Taskmux creates standard tmux sessions — all tmux commands work:

tmux attach-session -t myproject   # Attach to session
tmux list-sessions                 # List all sessions
# Ctrl+b 1/2/3 to switch windows, Ctrl+b d to detach

License

MIT