deviant/scripts/asm-sequencer/deploy

ASM sequencer — deploying under systemd

The sequencer service is a long-running HTTP daemon that holds the chain-tip for one backed asset category and serializes /claim requests into an ordered chain. It is a trust-minimised liveness service — the covenant enforces the swap math; the daemon can only order, delay, or refuse.

See ../README.md and wiki/asm/zero-contention-protocol.md for the full protocol context.

One-time host setup

1. Create the service user.

   sudo useradd -r -s /usr/sbin/nologin -d /nonexistent asm-seq
   

2. Lay out the code. The service file assumes /opt/deviant contains the repo. Easiest:

   sudo mkdir -p /opt/deviant
   sudo chown -R asm-seq:asm-seq /opt/deviant
   sudo -u asm-seq git clone <this-repo-url> /opt/deviant
   sudo -u asm-seq bash -c 'cd /opt/deviant && npm ci --omit=dev'
   

   Node 20+ required (import.meta.dirname, native fetch).

3. Install the coordinator wallet keyfile. The service reads .chipnet-keys-<COORD>.json from the repo root. For chipnet runs, copy .chipnet-keys-h.json into /opt/deviant/. Keep it mode 600 and owned by asm-seq.

   sudo cp /path/to/.chipnet-keys-h.json /opt/deviant/
   sudo chown asm-seq:asm-seq /opt/deviant/.chipnet-keys-h.json
   sudo chmod 600 /opt/deviant/.chipnet-keys-h.json
   

4. Install the token state file. The service reads ChipnetTests/.chipnet-<TOKEN>-token.json. Make sure that file ships with the deploy (it does today — ChipnetTests/ is dev state locally, but the specific token-state JSONs are small and can be copied to the host, or regenerated via scripts/chipnet-asm-genesis.mjs).

5. Create the environment file.

   sudo install -d -m 750 -o root -g asm-seq /etc/asm-sequencer
   sudo tee /etc/asm-sequencer/env > /dev/null <<'EOF'
   PORT=8710
   COORD=h
   TOKEN=asm2
   MAX_CHAIN_DEPTH=200
   EOF
   sudo chmod 640 /etc/asm-sequencer/env
   sudo chown root:asm-seq /etc/asm-sequencer/env
   

6. Install the unit.

   sudo install -m 644 /opt/deviant/scripts/asm-sequencer/deploy/asm-sequencer.service /etc/systemd/system/
   sudo systemctl daemon-reload
   sudo systemctl enable --now asm-sequencer
   sudo systemctl status asm-sequencer
   

Verifying

curl -s http://127.0.0.1:8710/health | jq

Expected: {ok: true, category, ticker, reservoir: {...}, coordinator: {...}, chainDepth, totalServed}.

Logs:

journalctl -u asm-sequencer -f

Reverse proxy

The daemon binds to 127.0.0.1:$PORT only. Expose it on a public host via nginx/caddy with TLS + rate limiting. Example nginx fragment:

location /asm-sequencer/ {
    proxy_pass http://127.0.0.1:8710/;
    proxy_read_timeout 30s;
    limit_req zone=asm_seq_zone burst=20 nodelay;  # define a 10 r/s zone in http {}
}

Updates & rollback

sudo -u asm-seq git -C /opt/deviant pull
sudo systemctl restart asm-sequencer

Rollback: git checkout <sha> on the deploy clone then restart.

Caveats

• In-memory state. Restart loses chainDepth, totalServed, lastError. The next /claim after restart re-fetches the on-chain tip (and if a prior chain is still unconfirmed, it will broadcast against the confirmed tip, which may txn-mempool-conflict with the still-pending chain — wait for a block before restarting under load).
• One category per service instance. Serve another asset by creating a second unit with its own PORT, COORD, TOKEN env.
• Chipnet-only token right now (chipnet provider hardcoded in server.mjs). Mainnet is a one-line swap once the mainnet token state file exists.
• Coordinator-funded trust model. The daemon holds the BCH funding. Users receive the FT; they do not need to sign anything. A user-funded variant (SIGHASH_ANYONECANPAY, /tip + /submit) removes this — see the server source for the newer endpoints.