PPA

Unofficial APT repository serving Discord, Postman, and zCLI on Linux.

A Go app that polls multiple upstream sources for new .deb releases, stores them in S3, generates GPG-signed APT metadata, and serves the repository over HTTPS. Deployed at ppa.matejpavlicek.cz.

Install

# 1. Download the signing key
curl -fsSL https://ppa.matejpavlicek.cz/key.gpg | sudo gpg --dearmor -o /usr/share/keyrings/ppa.gpg

# 2. Add the repository
echo "deb [arch=amd64 signed-by=/usr/share/keyrings/ppa.gpg] https://ppa.matejpavlicek.cz stable main" | sudo tee /etc/apt/sources.list.d/matej-pavlicek-ppa.list

# 3. Update and install
sudo apt update
sudo apt install discord postman   # install whichever packages you need

Updates are delivered automatically via apt upgrade.

How It Works

1. Each source (Discord, Postman, zCLI) has its own polling goroutine that checks for new upstream versions
2. When a new version is found, the .deb is downloaded (or built from a tar.gz), parsed, and uploaded to S3
3. APT metadata (Packages, Release, InRelease, Release.gpg) is regenerated and GPG-signed
4. An HTTP server proxies repository files from S3 to apt clients

Self-Hosting

Environment Variables

Variable	Required	Default	Description
GPG_PRIVATE_KEY	yes		Armored PGP private key (no passphrase)
S3_ENDPOINT	yes		S3-compatible endpoint
S3_BUCKET	yes		Bucket name
S3_ACCESS_KEY	yes
S3_SECRET_KEY	yes
S3_REGION	no	us-east-1
LISTEN_ADDR	no	:8080	HTTP listen address
ORIGIN	no	ppa.matejpavlicek.cz	APT Release Origin field
LABEL	no	PPA	APT Release Label field
DISCORD_DOWNLOAD_URL	no	Discord API	URL to poll for Discord .deb
DISCORD_POLL_INTERVAL	no	1h	Go duration string
POSTMAN_DOWNLOAD_URL	no	dl.pstmn.io/...	URL to poll for Postman tar.gz
POSTMAN_POLL_INTERVAL	no	6h	Go duration string
ZCLI_GITHUB_REPO	no		GitHub owner/repo (enables zCLI)
ZCLI_POLL_INTERVAL	no	1h	Go duration string

A .env file in the working directory is loaded automatically.

Build and Run

go build -o discord-ppa
./discord-ppa

Verify

./verify.sh                        # against production
./verify.sh http://localhost:8080   # against local instance

Local Development

1. Generate a test GPG key

Create a throwaway key with no passphrase (required by the app):

gpg --batch --gen-key <<EOF
%no-protection
Key-Type: RSA
Key-Length: 4096
Name-Real: PPA Dev
Name-Email: dev@localhost
Expire-Date: 1y
EOF

Export the private key in armored form:

gpg --armor --export-secret-keys dev@localhost

Copy the entire output (including the -----BEGIN PGP PRIVATE KEY BLOCK----- and -----END PGP PRIVATE KEY BLOCK----- lines).

2. Create a .env file

The app loads .env automatically (it is gitignored). Assuming your S3 storage is provided by Zerops, grab the credentials from the Zerops dashboard and create .env:

cat > .env <<'EOF'
GPG_PRIVATE_KEY=-----BEGIN PGP PRIVATE KEY BLOCK-----
<paste your full armored key here>
-----END PGP PRIVATE KEY BLOCK-----

S3_ENDPOINT=<your-zerops-s3-endpoint>
S3_BUCKET=<your-zerops-bucket-name>
S3_ACCESS_KEY=<your-zerops-access-key>
S3_SECRET_KEY=<your-zerops-secret-key>

LISTEN_ADDR=:8080

# Shorter intervals for development
DISCORD_POLL_INTERVAL=5m
POSTMAN_POLL_INTERVAL=10m

# Disable zCLI locally (omit ZCLI_GITHUB_REPO)
EOF

3. Run

go run .

The server starts at http://localhost:8080. On first run each source will poll immediately, so you should see Discord and Postman packages appear in S3 within a few minutes.

4. Test the APT repo locally

# Fetch the public key from your local server
curl -fsSL http://localhost:8080/key.gpg | sudo gpg --dearmor -o /usr/share/keyrings/ppa-dev.gpg

# Add a local sources entry
echo "deb [arch=amd64 signed-by=/usr/share/keyrings/ppa-dev.gpg] http://localhost:8080 stable main" | sudo tee /etc/apt/sources.list.d/ppa-dev.list

# Verify
sudo apt update
apt list --upgradable

5. Clean up the test GPG key

When you are done, remove the key from your local keyring:

gpg --delete-secret-and-public-keys dev@localhost

And remove the local APT config:

sudo rm /usr/share/keyrings/ppa-dev.gpg /etc/apt/sources.list.d/ppa-dev.list

Powered by Zerops

This project runs on Zerops ❤️ — a dev-first cloud platform that handles infrastructure so you can focus on code.

License

MIT