diff --git a/deploy/compose/README.md b/deploy/compose/README.md
index bb0e63fe15d..9371d97485c 100644
--- a/deploy/compose/README.md
+++ b/deploy/compose/README.md
@@ -3,6 +3,11 @@
 This is the single-node/VPS deployment bundle. It is intentionally separate from
 the root `docker-compose.yml`, which remains local development infrastructure.
 
+The Provably GCP pilot runs this bundle on one Compute Engine VM. It uses local
+Docker volumes for PostgreSQL, Redis, MinIO (S3-compatible media storage), and
+Buzz's Git path. MinIO is the storage service in this pilot; Google Cloud Storage
+is not required for the current deployment.
+
 ## Quick start
 
 ```bash
@@ -19,9 +24,9 @@ cd deploy/compose
 BUZZ_COMPOSE_TLS=true ./run.sh start
 ```
 
-The bootstrap script should eventually replace manual `.env` editing for normal
-users. It is responsible for generating stable secrets and, optionally, an owner
-keypair.
+For the Provably GCP pilot, `deploy/gcp/bootstrap.sh` fetches the runtime secrets
+from Google Secret Manager and writes a root-only `/opt/buzz/.env`. Do not commit
+that file or copy secret values into this repository.
 
 ## Production notes
 
@@ -29,7 +34,7 @@ keypair.
   `!reset` tag to remove the direct relay port when Caddy terminates HTTPS.
 - Default `BUZZ_IMAGE` tracks `ghcr.io/block/buzz:main` for early testing. Pin it to `ghcr.io/block/buzz:sha-<7>` or a semver release tag for production once available.
 - Keep `BUZZ_RELAY_PRIVATE_KEY`, `BUZZ_GIT_HOOK_HMAC_SECRET`, database/Redis,
-  and S3 secrets stable across restarts.
+  and MinIO/S3-compatible secrets stable across restarts.
 - `RELAY_OWNER_PUBKEY` is intentionally not prefixed with `BUZZ_`; it must be a
   64-character hex Nostr pubkey when closed relay mode is enabled.
 - `BUZZ_AUTO_MIGRATE` is opt-in. Set `BUZZ_AUTO_MIGRATE=true` or run
@@ -38,6 +43,9 @@ keypair.
   migrations.
 - The stack uses Postgres, Redis, MinIO, and a git data volume because
   those are real Buzz dependencies today. Minimal mode can simplify this later.
+  Treat the Git volume as scratch/cache until the pinned build's restore tests
+  prove otherwise; PostgreSQL and the object-store manifest are the intended
+  sources of truth for recovery planning.
 - The bundled Compose stack fixes the relay endpoint to `http://minio:9000` and
   `BUZZ_S3_ADDRESSING_STYLE=path`: Docker DNS resolves `minio`, not
   `<bucket>.minio`. It is not configurable for an external S3 provider through
diff --git a/deploy/gcp/README.md b/deploy/gcp/README.md
new file mode 100644
index 00000000000..b18cc890497
--- /dev/null
+++ b/deploy/gcp/README.md
@@ -0,0 +1,97 @@
+# Buzz on Google Cloud
+
+This directory documents the ProvablyAI GCP pilot and contains the VM bootstrap
+used for a future rebuild. The pilot is a single Compute Engine VM, not GKE.
+
+## Current topology
+
+- GCP project: `provably-buzz`
+- VM: `buzz-pilot-1` in `europe-west6-a`
+- Public domain: `buzz.provably.ai`
+- Relay endpoint: `wss://buzz.provably.ai`
+- Application image: `europe-west6-docker.pkg.dev/provably-buzz/buzz/buzz:4632c55`
+- Buzz source pin: `4632c55041c5d423d572a6f6411bb7b279c26f67`
+
+The application stack is Docker Compose under `/opt/buzz/src/deploy/compose`:
+
+| Service | Pilot role | Persistence |
+| --- | --- | --- |
+| `relay` | Buzz relay and HTTP bridge | `buzz-git-data` for the Git path |
+| `postgres` | Buzz operational database | `buzz-postgres-data` |
+| `redis` | Relay/runtime cache and coordination | `buzz-redis-data` |
+| `minio` | S3-compatible media/object storage | `buzz-minio-data` |
+| `minio-init` | Creates the private media bucket | no persistent state |
+
+The reverse proxy/TLS service is a separate Nginx Proxy Manager container, with
+Cloudflare in front of the public domain. It is intentionally not part of the
+application Compose file. The proxy-manager container may therefore appear as
+an orphan when the application Compose project is recreated; do not remove it
+unless the proxy deployment is being changed deliberately.
+
+## Secret handling
+
+The bootstrap reads these Secret Manager IDs using the VM runtime service
+account, then writes `/opt/buzz/.env` with root ownership and mode `0600`:
+
+```text
+Buzz_RELAY_OWNER_PUBKEY
+Buzz_RELAY_PRIVATE_KEY
+Buzz_GIT_HOOK_HMAC_SECRET
+Buzz_POSTGRES_PASSWORD
+Buzz_REDIS_PASSWORD
+Buzz_S3_ACCESS_KEY
+Buzz_S3_SECRET_KEY
+```
+
+The application environment variable names remain compatible with Buzz. The
+`Buzz_` prefix is the Secret Manager naming convention, not an instruction to
+rename the application variables. Secret values, private keys, and generated
+`.env` files must never be committed.
+
+The owner public key is public identity material and is not a password. The
+relay private key is an identity anchor; changing it is an identity migration,
+not a routine credential rotation. PostgreSQL and Redis credentials can be
+rotated with an explicit staged version and a controlled Compose recreation.
+
+## Bootstrap and verification
+
+`bootstrap.sh` is pinned to the tested Buzz image/source commit and performs the
+following operations:
+
+1. Installs Docker, Compose, Git, and the small bootstrap dependencies.
+2. Fetches Secret Manager values through the VM metadata service account.
+3. Clones Buzz and checks out the pinned source commit.
+4. Pulls the pinned Artifact Registry image.
+5. Links the generated environment into `deploy/compose/.env`.
+6. Starts the Compose stack and waits for health.
+
+The desktop invite flow requires all three origins in `BUZZ_CORS_ORIGINS`:
+
+```text
+https://buzz.provably.ai,http://tauri.localhost,tauri://localhost
+```
+
+After a deployment or rotation, verify:
+
+```bash
+curl -fsS https://buzz.provably.ai/_liveness
+curl -fsS https://buzz.provably.ai/_readiness
+```
+
+Expected responses are `ok` and `{"status":"ready"}`. Also verify ordinary
+relay connectivity, closed-membership behavior, media upload/download, Git
+paths, and the desktop invite flow before broader onboarding.
+
+## Recovery boundaries
+
+- Back up and rehearse restore for PostgreSQL and the MinIO bucket.
+- Preserve relay identity secrets and deployment configuration separately from
+  database/object data.
+- Treat the `buzz-git-data` volume as scratch/cache unless the pinned build and
+  restore tests prove it is authoritative. Do not treat it as the sole backup.
+- Keep a rollback environment snapshot and previous Secret Manager versions
+  until a rotation has passed health and functional checks.
+
+The current pilot deliberately uses local Docker PostgreSQL, Redis, and MinIO.
+Cloud SQL, Memorystore, Google Cloud Storage, GKE, and QEDB are later
+hardening/integration choices, not prerequisites for this baseline.
diff --git a/deploy/gcp/bootstrap.sh b/deploy/gcp/bootstrap.sh
new file mode 100755
index 00000000000..81afec0e21d
--- /dev/null
+++ b/deploy/gcp/bootstrap.sh
@@ -0,0 +1,82 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# GCP single-VM bootstrap for the pinned ProvablyAI Buzz image.
+# Secrets are fetched from Secret Manager at boot and written only to the
+# root-owned runtime file /opt/buzz/.env; this file is never committed.
+
+PROJECT_ID="provably-buzz"
+IMAGE_REGISTRY="europe-west6-docker.pkg.dev/provably-buzz/buzz/buzz:4632c55"
+LOCAL_IMAGE="provably/buzz:4632c55"
+BUZZ_SHA="4632c55041c5d423d572a6f6411bb7b279c26f67"
+BUZZ_DIR="/opt/buzz"
+TOKEN_URL="http://metadata.google.internal/computeMetadata/v1/instance/service-accounts/default/token"
+
+exec > >(tee -a /var/log/buzz-bootstrap.log | logger -t buzz-bootstrap) 2>&1
+
+export DEBIAN_FRONTEND=noninteractive
+apt-get update
+apt-get install -y ca-certificates curl docker.io docker-compose-v2 git python3
+systemctl enable --now docker
+
+install -d -m 0700 "$BUZZ_DIR"
+
+secret() {
+  local name="$1"
+  local token
+  token="$(curl -fsS -H 'Metadata-Flavor: Google' "$TOKEN_URL" | python3 -c 'import json,sys; print(json.load(sys.stdin)["access_token"])')"
+  curl -fsS \
+    -H 'Metadata-Flavor: Google' \
+    -H "Authorization: Bearer ${token}" \
+    "https://secretmanager.googleapis.com/v1/projects/${PROJECT_ID}/secrets/${name}/versions/latest:access" \
+    | python3 -c 'import base64,json,sys; print(base64.b64decode(json.load(sys.stdin)["payload"]["data"]).decode(), end="")'
+}
+
+install -o root -g root -m 0600 /dev/null "$BUZZ_DIR/.env"
+{
+  printf '%s\n' 'BUZZ_IMAGE=provably/buzz:4632c55'
+  printf '%s\n' 'BUZZ_DOMAIN=buzz.provably.ai'
+  printf '%s\n' 'RELAY_URL=wss://buzz.provably.ai'
+  printf '%s\n' 'BUZZ_MEDIA_BASE_URL=https://buzz.provably.ai/media'
+  printf '%s\n' 'BUZZ_MEDIA_SERVER_DOMAIN=buzz.provably.ai'
+  # The Tauri origins are required by the Buzz desktop invite flow.
+  printf '%s\n' 'BUZZ_CORS_ORIGINS=https://buzz.provably.ai,http://tauri.localhost,tauri://localhost'
+  printf '%s\n' 'BUZZ_REQUIRE_AUTH_TOKEN=true'
+  printf '%s\n' 'BUZZ_REQUIRE_RELAY_MEMBERSHIP=true'
+  printf '%s\n' 'BUZZ_ALLOW_NIP_OA_AUTH=true'
+  printf '%s\n' 'BUZZ_AUTO_MIGRATE=true'
+  printf '%s\n' 'BUZZ_GIT_CONFORMANCE_PROBE=true'
+  printf '%s\n' 'BUZZ_S3_ADDRESSING_STYLE=path'
+  printf '%s\n' 'BUZZ_S3_BUCKET=buzz-media'
+  printf '%s\n' 'BUZZ_HTTP_PORT=3000'
+  printf '%s\n' 'POSTGRES_DB=buzz'
+  printf '%s\n' 'POSTGRES_USER=buzz'
+  printf 'RELAY_OWNER_PUBKEY=%s\n' "$(secret Buzz_RELAY_OWNER_PUBKEY)"
+  printf 'BUZZ_RELAY_PRIVATE_KEY=%s\n' "$(secret Buzz_RELAY_PRIVATE_KEY)"
+  printf 'BUZZ_GIT_HOOK_HMAC_SECRET=%s\n' "$(secret Buzz_GIT_HOOK_HMAC_SECRET)"
+  printf 'POSTGRES_PASSWORD=%s\n' "$(secret Buzz_POSTGRES_PASSWORD)"
+  printf 'REDIS_PASSWORD=%s\n' "$(secret Buzz_REDIS_PASSWORD)"
+  printf 'BUZZ_S3_ACCESS_KEY=%s\n' "$(secret Buzz_S3_ACCESS_KEY)"
+  printf 'BUZZ_S3_SECRET_KEY=%s\n' "$(secret Buzz_S3_SECRET_KEY)"
+} > "$BUZZ_DIR/.env"
+chown root:root "$BUZZ_DIR/.env"
+chmod 0600 "$BUZZ_DIR/.env"
+
+install -d -m 0755 "$BUZZ_DIR/src"
+if [[ ! -d "$BUZZ_DIR/src/.git" ]]; then
+  git clone --no-tags --depth=1 https://github.com/ProvablyAI/buzz.git "$BUZZ_DIR/src"
+fi
+git -C "$BUZZ_DIR/src" fetch --depth=1 origin "$BUZZ_SHA"
+git -C "$BUZZ_DIR/src" checkout --detach "$BUZZ_SHA"
+
+registry_token="$(curl -fsS -H 'Metadata-Flavor: Google' "$TOKEN_URL" | python3 -c 'import json,sys; print(json.load(sys.stdin)["access_token"])')"
+printf '%s' "$registry_token" | docker login -u oauth2accesstoken --password-stdin https://europe-west6-docker.pkg.dev
+docker pull "$IMAGE_REGISTRY"
+docker tag "$IMAGE_REGISTRY" "$LOCAL_IMAGE"
+docker logout europe-west6-docker.pkg.dev >/dev/null 2>&1 || true
+
+ln -sfn "$BUZZ_DIR/.env" "$BUZZ_DIR/src/deploy/compose/.env"
+cd "$BUZZ_DIR/src/deploy/compose"
+docker compose --env-file "$BUZZ_DIR/.env" -f compose.yml up -d --wait --wait-timeout 300
+
+printf 'Buzz bootstrap completed for commit %s\n' "$BUZZ_SHA"