DevLens – Binary + Systemd Setup

This guide shows how to install the three DevLens components (app, agent, AI) from the binary releases and run each as a systemd service on a single host.

Prerequisites • A Linux distribution with systemd (Ubuntu, Debian, CentOS, RHEL, etc.) • curl / wget for downloading files • tar for extracting archives

Supported OSes – see the release page: https://source.rdctd.de/devlens/releases

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1. Prepare the host

Create a dedicated user and directories:

sudo useradd -r -s /usr/sbin/nologin devlens
sudo mkdir -p /opt/devlens
sudo chown devlens:devlens /opt/devlens

The data directory (where the DB, logs and retention data live) should be writable by that user:

sudo mkdir -p /var/lib/devlens
sudo chown devlens:devlens /var/lib/devlens

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2. Download and install the binaries

Step 1 – Grab the latest release Replace <VERSION> with the tag you want to use (1.2.3, latest, …).

VERSION=latest
curl -L "https://source.rdctd.de/devlens/releases/devlens-${VERSION}.tar.gz" | \
    tar -xz -C /opt/devlens

The archive contains:

/opt/devlens/
├─ app
├─ agent
├─ ai
└─ README.md

Make sure each binary is executable:

sudo chmod 755 /opt/devlens/{app,agent,ai}

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3. Write systemd unit files

Create three unit files under /etc/systemd/system/:

3.1 devlens-app.service

[Unit]
Description=DevLens App – UI & alert dispatcher
After=network.target

[Service]
User=devlens
Group=devlens
WorkingDirectory=/opt/devlens
ExecStart=/opt/devlens/app -config=/var/lib/devlens/devlens.toml
Restart=on-failure

[Install]
WantedBy=multi-user.target

3.2 devlens-agent.service

[Unit]
Description=DevLens Agent – host telemetry collector
After=network.target

[Service]
User=devlens
Group=devlens
WorkingDirectory=/opt/devlens
ExecStart=/opt/devlens/agent -config=/var/lib/devlens/devlens.toml
Restart=on-failure

[Install]
WantedBy=multi-user.target

4.3 devlens-ai.service

[Unit]
Description=DevLens AI – LLM-based fix suggestions
After=network.target

[Service]
User=devlens
Group=devlens
WorkingDirectory=/opt/devlens
ExecStart=/opt/devlens/ai -config=/var/lib/devlens/devlens.toml
Restart=on-failure

[Install]
WantedBy=multi-user.target

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4. Enable and start the services

sudo systemctl daemon-reload

sudo systemctl enable devlens-app
sudo systemctl enable devlens-agent
sudo systemctl enable devlens-ai

sudo systemctl start devlens-app
sudo systemctl start devlens-agent
sudo systemctl start devlens-ai

Verify everything is running:

systemctl status devlens-{app,agent,ai}

You should see each service in the active (running) state.

Open a browser to http://<host-ip>:8000 – the DevLens UI should be live.

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5. Updating to a new version

1. Stop the services bash sudo systemctl stop devlens-{app,agent,ai}

2. Download & replace the binaries (step 2, but use the new <VERSION>).

3. Start the services again bash sudo systemctl start devlens-{app,agent,ai}

4. Check logs bash journalctl -u devlens-app -f

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7. Cleaning up

To remove the services and data:

sudo systemctl stop devlens-{app,agent,ai}
sudo systemctl disable devlens-{app,agent,ai}
sudo rm /etc/systemd/system/devlens-*.service
sudo systemctl daemon-reload

# Optional: delete binaries and data
sudo rm -rf /opt/devlens
sudo rm -rf /var/lib/devlens

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Quick Recap

Step	Action
1	Create devlens user & directories
2	Download and unpack binaries to /opt/devlens
3	Write devlens.toml in /var/lib/devlens
4	Add systemd unit files (devlens-app, devlens-agent, devlens-ai)
5	Enable/start services with systemctl
6	Verify UI at :8000
7	Update by downloading new binaries & restarting services