OCL Nexus Local is an open-source compute fabric that provides a frictionless, local-first environment for agentic development. Built on a single-node K3s architecture via Docker Compose, it allows developers to provision isolated Ubuntu sandboxes with native Model Context Protocol (MCP) support directly on their own hardware. Designed for 100% parity with the OCL Nexus cloud platform, it enables AI agents to autonomously manage the full lifecycle of micro-workloads—from code shipment and dependency scaling to real-time service orchestration—without the complexity of manual infrastructure management.

For live internet workloads requiring 24/7 availability and high-performance compute on dedicated EU-based NVMe infrastructure, visit oclnexus.com.

Prerequisites

• Docker Desktop or Docker Engine + Docker Compose
• 8 GB+ RAM (allocate in Docker Desktop → Settings → Resources)
• 10 GB disk space
• macOS, Linux, or Windows (WSL2 required on Windows)

Quick Start

1. Generate an encryption key

The key must be exactly 32 ASCII characters (used as raw AES-256-GCM key bytes):

python3 -c "import secrets; print(secrets.token_urlsafe(24)[:32])"
# or
openssl rand -base64 24 | head -c 32

2. Configure environment

cp .env.local.example .env.local

Edit .env.local and set your generated key:

ENCRYPTION_KEY=your-generated-32-char-key-here

3. Start the stack

docker compose up -d

First-time startup takes 3–5 minutes — K3s must pull system images (CoreDNS, Traefik, metrics-server) and initialise the cluster. Subsequent starts take ~30 seconds.

4. Retrieve your API key

docker compose logs nexus-init | grep -A 5 "nx_"

Copy the nx_... key — it is shown only once and is required for MCP and REST API access.

5. Open the dashboard

http://localhost:3000/dashboard — no login required.

Workload DNS

Deployed workloads are served at http://inst-{id}.{INFRA_DOMAIN}. The default INFRA_DOMAIN is localhost.

Option A — Zero config, needs internet: localtest.me

*.localtest.me is a public DNS service that resolves every subdomain to 127.0.0.1.

In .env.local (or docker-compose.yml):

INFRA_DOMAIN=localtest.me

Workloads become accessible at http://inst-{id}.localtest.me.

Option B — Offline: configure wildcard DNS for *.localhost

macOS (one-time, 3 commands):

brew install dnsmasq
echo "address=/.localhost/127.0.0.1" >> $(brew --prefix)/etc/dnsmasq.conf
brew services start dnsmasq
sudo mkdir -p /etc/resolver
echo "nameserver 127.0.0.1" | sudo tee /etc/resolver/localhost

Linux (older, no systemd-resolved):

sudo apt install dnsmasq
echo "address=/.localhost/127.0.0.1" | sudo tee /etc/dnsmasq.d/localhost-wildcard.conf
sudo systemctl restart dnsmasq

Keep INFRA_DOMAIN=localhost (the default) after either step.

MCP Integration (Claude Desktop)

Edit your Claude Desktop config:

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

{
  "mcpServers": {
    "nexus": {
      "command": "curl",
      "args": [
        "-X", "POST",
        "http://localhost:3000/api/mcp/v1",
        "-H", "Content-Type: application/json",
        "-H", "Accept: application/json, text/event-stream",
        "-H", "Authorization: Bearer nx_YOUR_KEY_HERE",
        "-d", "@-"
      ]
    }
  }
}

Replace nx_YOUR_KEY_HERE with the key from step 4 and restart Claude Desktop.

Verify the connection:

curl -X POST http://localhost:3000/api/mcp/v1 \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -H "Authorization: Bearer nx_YOUR_KEY_HERE" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' \
  | grep '^data:' | sed 's/^data: //' | python3 -m json.tool

You should see 15 MCP tools listed (nexus_deploy, nexus_list_workloads, nexus_execute_command, etc.).

The Accept: application/json, text/event-stream header is required. Omitting it returns a 406 Not Acceptable error.

What's Running

Developer Mode (Hot Reload)

For iterating on the platform itself, a dev compose override mounts the source tree live and runs npm run dev instead of the pre-built production server:

docker compose -f docker-compose.yml -f docker-compose.dev.yml up

File changes in src/ are reflected in the browser within ~1 second. No container restart needed.

If you add or remove npm packages, rebuild the image to re-run npm ci:

docker compose -f docker-compose.yml -f docker-compose.dev.yml up --build nexus-app

Testing

Integration tests live in tests/. They run against a live stack.

Setup

cp tests/.env.test.example tests/.env.test

Edit tests/.env.test — set your API key (from step 4 of Quick Start) and confirm the URLs match your setup:

NEXUS_API_KEY=nx_your_key_here
NEXUS_BASE_URL=http://localhost:3000
INFRA_DOMAIN=localhost

Run

npm run test:api        # M2M lifecycle: deploy → upload → execute → delete
npm run test:python     # Flask service mode + public URL access
npm run test:node       # Express service mode + public URL access
npm run test:discovery  # Blueprint list API
npm run test:ui         # UI path: deploy → poll → restart → delete

All tests clean up after themselves. Set SKIP_CLEANUP=true in tests/.env.test to preserve instances for inspection.

See tests/README.md for full details.

Common Commands

# Status
docker compose ps

# Logs
docker compose logs -f nexus-app
docker compose logs nexus-k3s

# Stop (keeps data)
docker compose down

# Stop and delete all data
docker compose down -v

# Inspect the K3s cluster
docker compose exec nexus-k3s k3s kubectl get pods -A
docker compose exec nexus-k3s k3s kubectl get ingress -A

Advanced

Access the Kubernetes cluster from the host

docker compose exec nexus-k3s cat /shared/k3s/kubeconfig > kubeconfig.local
export KUBECONFIG=./kubeconfig.local
kubectl get nodes
kubectl get pods -A

Database access

# psql CLI
docker compose exec nexus-db psql -U nexus -d nexus

# pgweb UI
open http://localhost:8082

Backup and restore

# Backup
docker compose exec nexus-db pg_dump -U nexus nexus > backup.sql

# Restore
docker compose exec -T nexus-db psql -U nexus nexus < backup.sql

Troubleshooting

Port conflict (3000, 80, or 443 already in use)

Edit docker-compose.yml and change the host-side port:

ports:
  - "3001:3000"   # dashboard now at http://localhost:3001/dashboard

K3s won't start / keeps restarting

1. Increase Docker memory to 8 GB minimum (Docker Desktop → Settings → Resources).
2. Force-recreate the container: docker compose up -d --force-recreate nexus-k3s

Workload returns 404 immediately after deploy

Traefik may still be starting. Wait 30–60 seconds after K3s reports healthy, then retry. Traefik pulls its image (~130 MB) on first run.

No API key in logs

Re-run the init container:

docker compose run --rm nexus-init

Database connection error

Wait for nexus-db to reach the healthy state (not just "running"):

docker compose ps   # check STATUS column
docker compose restart nexus-db nexus-app

Full reset (deletes all workload data)

docker compose down -v
docker compose up -d
docker compose logs nexus-init | grep "nx_"   # retrieve new API key

Architecture

┌─────────────────────────────────────────────────────────────┐
│                        Your Machine                         │
│                                                             │
│  ┌───────────────────────────────────────────────────────┐  │
│  │  Docker Compose                                       │  │
│  │                                                       │  │
│  │  ┌────────────┐  ┌────────────┐  ┌────────────────┐   │  │
│  │  │ nexus-app  │  │ nexus-db   │  │   nexus-k3s    │   │  │
│  │  │ (Next.js)  │  │ (Postgres) │  │ K3s + Traefik  │   │  │
│  │  │ Port 3000  │  │ Port 5432  │  │  Port 80/443   │   │  │
│  │  └────────────┘  └────────────┘  └────────────────┘   │  │
│  │                                                       │  │
│  │  ┌────────────────────────────────────────────────┐   │  │
│  │  │  Volumes: nexus-db-data, nexus-k3s-data        │   │  │
│  │  └────────────────────────────────────────────────┘   │  │
│  └───────────────────────────────────────────────────────┘  │
│                                                             │
│  Dashboard  → http://localhost:3000/dashboard               │
│  Workloads  → http://inst-{id}.localhost                    │
└─────────────────────────────────────────────────────────────┘

Related files

Community

• Discord: Join the #ocl-nexus-local channel
• Issues: GitHub Issues for bugs and feature requests
• Security: See SECURITY.md — please email rather than opening a public issue for vulnerabilities
• Contributing: See CONTRIBUTING.md

License

This project is licensed under the GNU Affero General Public License v3.0 (AGPL-3.0). See the LICENSE file for details.