Show HN: Paca – Lightweight Jira alternative for human-AI collaboration

AI-native. Free. Lightweight. Open-source.

Getting Started · MCP Server · Claude Code Skill · Architecture · Contributing · Roadmap

Paca is a self-hosted project management platform where AI agents and humans collaborate as equal teammates inside a Scrum team — not as chatbots bolted on the side.

Jira gives you a backlog. ClickUp gives you automations. Monday gives you dashboards. Paca gives your AI agents a seat at the table. They join sprint planning, pick up tasks from the board, write BDD specs, and adapt alongside humans in real time.

Everything about Paca — its workflow, its data model, its UI — is configurable and extendable via plugins.

The central insight behind Paca is that AI agents should participate in the Scrum process, not just generate output in isolation.

In Paca, AI agents:

• Are assigned to sprints and appear on the Scrumban board alongside human teammates
• Pick up tasks from the backlog and update their status in real time
• Collaborate on BDD specs — helping Product Owners and BAs write Gherkin scenarios
• Contribute to System Design Documents — keeping the architecture visible to the whole team
• Probe, sense, and respond to emerging complexity, just like a human would

This is not automation. It is genuine collaboration — rooted in the Cynefin / Stacey framework's recognition that complex domains require teams, not pipelines.

Paca ships as a small, focused core. Everything else is optional.

Configuration-driven: workflows, statuses, field definitions, board layouts, sprint rules, and agent behavior are all driven by project-level configuration files. No code needed to adapt Paca to your team's process.

Plugin system: extend or replace any part of Paca via plugins. Plugins are compiled to WebAssembly (WASM) for the backend (write in Go, Rust, AssemblyScript — anything with a WASM target) and standard module bundles for the frontend. Plugins run in a sandboxed environment with a capability-based permission model; they declare exactly what host functions they need, and nothing more.

plugins/
├── backend/        # WASM modules — add custom routes, logic, data models
└── frontend/       # UI modules — add custom pages, board views, widgets

Browse and install community plugins directly from the Plugin Marketplace inside the Paca UI — no command line required. Go to Settings → Plugins → Marketplace, find a plugin, and click Install.

For local development or custom plugins, you can also install from the filesystem:

./scripts/install-local-plugin.sh ./my-plugin --api-key <your-api-key>

Paca structures team collaboration around four phases that mirror both Scrum and the scientific method:

Plan  →  Act  →  Check  →  Adapt
  ↑                             |
  └─────────────────────────────┘

• In-app AI chat — chat with AI agents at the project level to plan work, create or update epics, stories, tasks, and documentation — all in plain English without leaving Paca

• Activity diff & revert — every field change in the activity pane now shows a before/after diff; one click reverts a change to its previous value

• Unified Scrumban Board — humans and AI agents share a single real-time board; no separate "AI workspace"
• In-app AI chat — chat with AI agents at the project level to plan work, create or update epics, stories, tasks, and documentation in plain English
• Activity diff & revert — see a visual diff for every field change in the activity pane and revert any change with one click
• BDD Collaboration — Gherkin scenario editor co-authored by POs, BAs, and AI agents
• System Design Documents (SDD) — living architecture docs that keep AI agents contextually grounded
• MCP Server — connect Claude, custom agents, or any MCP-compatible tool directly into Paca's data layer
• Claude Code skill — /paca slash command for Claude Code; manage tasks, docs, and sprints in plain English without leaving your editor
• Real-time updates — Socket.IO delivery; everyone sees changes the moment they happen
• OpenHands-powered agents — AI agents run on the OpenHands SDK; each agent executes inside its own isolated sandbox container so your host environment is never touched
• WASM plugin sandbox — extend Paca safely; plugins cannot escape their declared permissions
• Self-hosted — runs on a single Docker Compose command; your data never leaves your infrastructure
• Lightweight by default — minimal core, no feature bloat; add only what your team actually needs

Runs on any Linux server with Docker. No repository clone required.

curl -fsSL https://github.com/Paca-AI/paca/releases/latest/download/install.sh | bash

The script walks you through configuration interactively and starts the full stack. Open http://your-server-ip when it finishes.

# 1. Create a directory and download the compose file
mkdir paca && cd paca
curl -fsSL https://github.com/Paca-AI/paca/releases/latest/download/docker-compose.yml -o docker-compose.yml
mkdir -p nginx
curl -fsSL https://github.com/Paca-AI/paca/releases/latest/download/gateway.conf -o nginx/gateway.conf

# 2. Create your environment file
cat > .env <<'EOF'
JWT_SECRET=<run: openssl rand -hex 32>
ADMIN_PASSWORD=<your-admin-password>
POSTGRES_PASSWORD=<run: openssl rand -hex 32>
AGENT_API_KEY=<run: openssl rand -hex 32>
INTERNAL_API_KEY=<run: openssl rand -hex 32>
ENCRYPTION_KEY=<run: openssl rand -hex 32>
PUBLIC_URL=http://localhost
EOF

# 3. Start the stack
docker compose --env-file .env up -d

Open http://localhost — log in with admin and the password you set.

Customizing the stack: scale down services you don't need.

# External PostgreSQL (supply DATABASE_URL in .env)
docker compose --env-file .env up -d --scale postgres=0

# AWS S3 instead of MinIO (set STORAGE_PROVIDER=s3 in .env)
docker compose --env-file .env up -d --scale minio=0

# Without the AI agent (reduces resource usage)
docker compose --env-file .env up -d --scale ai-agent=0

From the directory where your docker-compose.yml lives:

docker compose pull
docker compose --env-file .env up -d

Database migrations run automatically on API startup.

# Clone the repository
git clone https://github.com/Paca-AI/paca.git && cd paca

# Start infrastructure dependencies (PostgreSQL + Valkey)
docker compose -f deploy/docker-compose.dev.yml up -d postgres valkey

# Or start the full dev stack in containers
docker compose -f deploy/docker-compose.dev.yml up -d

See docs/guides/local-development.md for running services on the host for active development.

Paca ships an MCP (Model Context Protocol) server that gives any compatible AI agent direct, structured access to your workspace — projects, tasks, sprints, documents, members, and more. No scraping, no custom APIs to wire up.

The server is published as @paca-ai/paca-mcp on npm. You run it with npx; your MCP client handles the rest.

1. Open (or create) the Claude Desktop config file:

   • macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
   • Windows: %APPDATA%\Claude\claude_desktop_config.json

2. Add the paca entry:

{
  "mcpServers": {
    "paca": {
      "command": "npx",
      "args": ["-y", "@paca-ai/paca-mcp"],
      "env": {
        "PACA_API_KEY": "your-api-key-here",
        "PACA_API_URL": "http://localhost:8080"
      }
    }
  }
}

3. Restart Claude Desktop. Claude now has access to all Paca tools and can answer requests like:
   • "List all active sprints in project X"
   • "Create a task for implementing OAuth and assign it to sprint 3"
   • "Add a comment to task #42 with my progress update"

Any client that speaks MCP works. Typical configuration:

{
  "name": "paca",
  "command": "npx",
  "args": ["-y", "@paca-ai/paca-mcp"],
  "env": {
    "PACA_API_KEY": "your-api-key-here",
    "PACA_API_URL": "http://your-paca-instance:8080"
  }
}

The server exposes tools across these categories:

For a complete reference and advanced configuration (agent-mode, plugin tools, programmatic usage), see docs/guides/mcp-server-setup.md.

If you use Claude Code, install the Paca skill set and manage your entire Paca workspace through natural-language slash commands — without leaving your editor and without creating local files. Every command reads your Paca documentation first to understand the project before acting.

Skills are defined in the skills/ directory using the Agent Skills format — one subdirectory per skill, each with a SKILL.md containing YAML frontmatter and instructions. The install script strips the frontmatter and writes the body to ~/.claude/commands/ for use as Claude Code slash commands.

Run this once in your terminal to install all skills globally:

curl -fsSL https://raw.githubusercontent.com/Paca-AI/paca/master/scripts/install-claude-skill.sh | bash

Then connect the Paca MCP server to Claude Code:

claude mcp add paca \
  --env PACA_API_KEY=<your-api-key> \
  --env PACA_API_URL=<your-paca-url> \
  -- npx -y @paca-ai/paca-mcp

Run /paca-setup inside a Claude Code session for a guided interactive walkthrough instead.

For full setup options and command reference, see docs/guides/claude-code-skill.md.

apps/web          React + TanStack Start + shadcn/ui — user interface
apps/mcp          @paca-ai/paca-mcp — MCP server for AI agent integration
services/api      Go + Gin — core business logic and REST API
services/realtime Node.js + Socket.IO — real-time event fan-out
services/ai-agent Python + FastAPI + OpenHands SDK — AI agent orchestration
apps/e2e          Playwright — end-to-end test suite

skills/           Agent Skills — /paca slash commands for Claude Code

PostgreSQL        Persistent store
Valkey            Cache + async event streams between services

See docs/architecture/overview.md for detail.

The name is a small pun on the Japanese word "Baka" (ばか) — "silly."

In the early days, we jokingly called our AI assistants "silly" when they hallucinated. And building a serious project management platform as a free, open-source alternative to multi-billion-dollar tools might also seem a bit silly.

But Paca is built from conviction: human-AI collaboration in a real Scrum team should be accessible to every team, everywhere — not locked behind a vendor's pricing model. We think that's worth being a little foolish about. 🦙✨

Distributed under the Apache License 2.0. See LICENSE for details.