DployDB is being built as a deployment-safety tool for applications that use one SQLite database on one Linux server.

This path starts a real v1 Docker Compose application and SQLite database, then uses the installed dploydb CLI—not the fixture controller—to rehearse, validate, and deploy v2. Run it from a checked-out DployDB source tree on Linux with Python 3.12+, pipx, Docker Engine, and the Docker Compose plugin.

python3 --version  # must report 3.12 or newer
pipx --version
docker version
docker compose version

git clone https://github.com/recursiveway/dployDB.git
cd dployDB
pipx install dploydb==0.1.1
dploydb --no-color version

Create the known-good v1 application, then generate private absolute-path demo configuration. start-v1 intentionally resets only the selected quickstart demo instance.

python3 demo/controller.py --instance quickstart --port 4510 start-v1
python3 -m demo.prepare \
  --instance quickstart --port 4510 --candidate-port 4511
. demo/.state/quickstart/dploydb.env

Run the complete host audit and deploy v2 with machine-readable output:

dploydb --no-color doctor --deep \
  --config demo/.state/quickstart/dploydb.yaml
dploydb --no-color deploy --version v2 \
  --config demo/.state/quickstart/dploydb.yaml \
  --json --non-interactive > /tmp/dploydb-quickstart-result.json
python3 -c 'import json; p=json.load(open("/tmp/dploydb-quickstart-result.json")); assert p["ok"] is True and p["outcome"] == "active"; print(p["release_id"])'
curl --fail-with-body http://127.0.0.1:4510/health
dploydb releases --config demo/.state/quickstart/dploydb.yaml

The JSON assertion proves CI can parse the real deployment result. The v1 database is migrated to schema version 2, the candidate is tested on an isolated copy and port, and normal traffic is activated only after final production checks. Stop the demo container without deleting its database, backups, or release evidence:

python3 demo/controller.py --instance quickstart --port 4510 stop

If either port is already occupied, choose two unused distinct ports in all three commands. For production setup, continue with the first-run guide, Nginx hook example, security model, limitations, and backup-preserving uninstall.

Milestones 0 through 8 provide:

• an installable dploydb CLI with help and version commands;
• strict, duplicate-safe configuration parsing with environment interpolation;
• in-memory secret registration and output redaction;
• dploydb init, which creates a valid mode-0600 starter file without overwriting;
• atomic generic operation manifests and append-only, redacted event logs;
• a durable fcntl.flock deployment lock with atomic owner metadata and stale-owner diagnosis;
• bounded, redacted subprocess execution with process-group timeout cleanup;
• dploydb doctor, with layered host checks, bounded SQLite verification, and explicit deferred checks;
• read-only dploydb status, including active, interrupted, stale, and recovery-required state;
• SQLite online backups that remain consistent while the application is writing;
• immutable mode-0600 backup databases and metadata under a mode-0700 directory;
• dploydb backup [--upload] and read-only dploydb verify <backup-id> with stable JSON output;
• S3-compatible off-server replication, including Cloudflare R2, with local verification before upload, database-first/metadata-last commit, full remote readback verification, bounded requests/retries, and runtime-only credentials;
• verified remote hydration when a protected local backup is absent, used by manual restore and interrupted-operation recovery without accepting corrupt local evidence;
• an internal stopped-application restore engine that creates a verified pre-restore backup and restores it automatically if replacement fails;
• an internal, lock-protected migration rehearsal stage that creates a verified snapshot, migrates only a private disposable copy, captures redacted command evidence, enforces process-tree timeout cleanup, reruns SQLite checks, and records rehearsal_passed or a durable failed-safe result;
• an internal Docker Compose candidate runner that creates an operation-scoped one-off project, binds only the configured loopback candidate port, overlays the rehearsed SQLite directory at the configured container target, validates live mounts/ports/labels before acceptance, captures bounded redacted logs, and proves idempotent container/network cleanup;
• a public dploydb deploy --version <version> command that runs verified backup, migration rehearsal, isolated candidate checks, controlled maintenance, stopped-writer final backup, production migration, final application/database checks, and traffic activation under one durable lock;
• exact previous-container preservation and automatic application/database rollback for failures before new traffic activation, with durable release, hook, health, checksum, and event evidence;
• required final-backup replication before production migration, plus post-activation local/remote retention that always protects the active and immediately previous releases' rehearsal and final backups;
• read-only dploydb releases and dploydb release show <release-id> history with validated active/previous pointers and preserved failure evidence;
• dploydb restore <release-id>, which previews the protected immediately previous release, warns about data loss, and creates a verified backup of the current state before any confirmed database replacement;
• dploydb recover, which reconciles durable intent, backups, checksums, exact Docker resources, traffic evidence, and the OS lock before offering an idempotent recovery plan;
• real abrupt-process crash tests after maintenance, current-app stop, and production migration, plus a real backup-first previous-release restore;
• a deterministic Docker Compose demo application;
• working v1 and v2 release fixtures;
• a deliberately broken migration fixture;
• a deliberately unhealthy application fixture;
• a production-only final-health failure fixture used to prove real cutover rollback after candidate validation passes;
• real SQLite reads, writes, and data-preserving migration behavior.
• explicit ANSI-free --no-color/NO_COLOR behavior and installed help audits for every required command;
• finite per-operation evidence logs, with byte and record-count limits that preserve append-only failure evidence;
• a clean-Linux-tested installed-CLI quick start, production first-run guide, validated Nginx traffic hooks, security/limitations guidance, and an uninstall path proven to preserve database, backup, release, and event bytes.

The demo controller is not the DployDB deployment engine. Migration rehearsal and candidate validation are internal stages of the public deployment engine. Controlled production cutover, automatic pre-traffic rollback, release-aware manual restore, interrupted-operation recovery, verified off-server backup, and protected retention are implemented.

• Python 3.12 or newer
• pipx for an isolated end-user installation
• Docker Engine or Docker Desktop
• Docker Compose

Install the published Alpha CLI:

pipx install dploydb==0.1.1
dploydb version

Contributors can install the checked-out source tree with pipx install ..

Repository development and validation use uv:

uv sync --locked

Reset the default demo database, apply the v1 migration, build the image, start the single Compose application service, and verify HTTP health:

uv run python demo/controller.py start-v1

The application is available at http://127.0.0.1:4510. Its real SQLite database is stored at:

demo/.state/default/data/app.db

Create and read data through the application:

curl --fail-with-body \
  --header 'Content-Type: application/json' \
  --data '{"body":"written under v1"}' \
  http://127.0.0.1:4510/notes

curl --fail-with-body http://127.0.0.1:4510/notes

Stop the container without deleting the database, then start v1 against the same data:

uv run python demo/controller.py stop
uv run python demo/controller.py start v1

Running start-v1 again intentionally resets the default instance to an empty v1 database.

Start v1 and create a note first, then stop application writes and apply the v2 fixture migration:

uv run python demo/controller.py stop
uv run python demo/controller.py migrate v2
uv run python demo/controller.py start v2

The v1 note is preserved with the default category general. V2 also accepts an explicit category:

curl --fail-with-body \
  --header 'Content-Type: application/json' \
  --data '{"body":"written under v2","category":"deployment"}' \
  http://127.0.0.1:4510/notes

These commands are deterministic fixture controls, not safe deployment orchestration.

After adapting the generated configuration to the real absolute database, Compose, backup, health, migration, and traffic-hook paths, deploy with:

dploydb deploy --version v2 --config /absolute/path/to/dploydb.yaml
dploydb deploy --version v2 --config /absolute/path/to/dploydb.yaml \
  --json --non-interactive

The command does not modify production until the verified snapshot, migration rehearsal, and isolated candidate checks pass. During cutover it enables maintenance, stops the exact current container, creates and verifies a final backup, migrates production, starts and checks the new application while normal traffic remains blocked, then activates traffic and records the release. When backup.remote.required is true, the stopped-writer final backup must be committed and read back from remote storage before production migration intent is recorded. A failed upload restarts and verifies the previous application without migrating or restoring the unchanged database.

If a failure occurs before traffic activation, DployDB restores the final backup when needed, restarts the exact previous container, activates the old target, disables maintenance, verifies the old application/database, and returns an outcome of rolled_back. Once new traffic may be active, DployDB does not automatically restore the old database; uncertain routing or post-activation failure is reported as recovery_required with the evidence log and next safe action.

List validated local history or inspect one immutable release record:

dploydb releases --config /absolute/path/to/dploydb.yaml
dploydb releases --config /absolute/path/to/dploydb.yaml --json
dploydb release show release_0123456789abcdef0123456789abcdef \
  --config /absolute/path/to/dploydb.yaml --json

Manual restore is intentionally limited to the protected immediately previous release. Previewing is read-only and prints the exact application, database backup, checksum, and data-loss warning:

dploydb restore release_0123456789abcdef0123456789abcdef \
  --config /absolute/path/to/dploydb.yaml
dploydb restore release_0123456789abcdef0123456789abcdef \
  --config /absolute/path/to/dploydb.yaml --json

After reviewing the preview, confirm interactively or use --yes explicitly:

dploydb restore release_0123456789abcdef0123456789abcdef \
  --config /absolute/path/to/dploydb.yaml --yes

DployDB revalidates the selection under the deployment lock, enables maintenance, stops the current writer, creates and verifies a PRE_RESTORE backup, restores the selected database, restarts and checks the selected application, switches traffic, and then swaps active/previous pointers. A pre-traffic failure restores and verifies the pre-restore database and current application. Once selected traffic may have been exposed, DployDB does not automatically replace the database again.

status reports an abrupt or contradictory operation with exit code 60. Diagnose it without mutation:

dploydb recover --config /absolute/path/to/dploydb.yaml
dploydb recover --config /absolute/path/to/dploydb.yaml --json

An executable plan lists its exact ordered actions and requires confirmation. Run it interactively or acknowledge it explicitly:

dploydb recover --config /absolute/path/to/dploydb.yaml --yes

Recovery can return to the verified previous application/database when traffic was not activated, or finish an already checked new release when durable hook evidence proves activation succeeded. If traffic activation is uncertain, backup lineage conflicts, live identities cannot be proven, or unrelated operations are unfinished, it refuses automatic mutation with recovery_required, the evidence log, and the next safe action. Re-running a partially interrupted recovery re-inspects live state and skips database replacement when the checksum already matches the verified target.

Return to a clean v1 database and create data, then stop the application:

uv run python demo/controller.py start-v1
curl --fail-with-body \
  --header 'Content-Type: application/json' \
  --data '{"body":"must survive"}' \
  http://127.0.0.1:4510/notes
uv run python demo/controller.py stop

Run the broken migration:

uv run python demo/controller.py migrate broken-migration

It exits nonzero with the stable SQLite reason no such table: deliberate_missing_table. The migration is transactional, so the v1 schema and note remain unchanged. Restart v1 to inspect them:

uv run python demo/controller.py start v1
curl --fail-with-body http://127.0.0.1:4510/notes

The broken-health fixture performs a valid v1-to-v2 migration, starts normally, reads SQLite successfully, and then deliberately returns HTTP 503 from /health:

uv run python demo/controller.py start-v1
uv run python demo/controller.py stop
uv run python demo/controller.py migrate broken-health
uv run python demo/controller.py up broken-health
uv run python demo/controller.py health

The last command exits nonzero and reports fixture_broken_health. To inspect the response directly:

curl --include http://127.0.0.1:4510/health

Use separate state and Compose projects with global options placed before the command:

uv run python demo/controller.py --instance second --port 4520 start-v1
uv run python demo/controller.py --instance second --port 4520 stop

Generated databases live below demo/.state/<instance>/ and are ignored by Git. stop preserves the selected database. reset stops the service and recreates a clean migrated v1 database without starting it:

uv run python demo/controller.py reset

Run the complete repository suite:

uv lock --check
uv sync --locked --check
uv run pytest -q
uv run ruff check .
uv run ruff format --check .
uv run mypy dploydb
uv run mypy demo
uv build
uv run python scripts/verify_pipx_install.py

The Docker integration tests require a running Docker daemon and perform their own Compose cleanup.

Create a restrictive starter configuration without overwriting an existing path:

uv run dploydb init

The generated dploydb.yaml is strict: duplicate keys, unknown fields, unsafe candidate URLs, relative production paths, shell-style command strings, and invalid timeout/retention values are rejected. ${VARIABLE} interpolation is resolved only after structural validation. Host and database checks are kept out of parsing and performed by doctor or the relevant lock-tracked operation. Candidate isolation defaults to container port 8080 and database volume target /data; set application.candidate_container_port and application.database_volume_target explicitly when the Compose service uses different container-side values. Compose files may use the reserved DPLOYDB_VERSION interpolation value; test-mode configuration cannot override it. Production deployment additionally requires application.production_project, application.production_port, and application.production_health_url, with a distinct candidate port. All four traffic commands are bounded argument arrays; they must implement maintenance on/off and new/old target activation idempotently.

demo/dploydb.yaml is another valid example for the deterministic fixture. Its /srv/dploydb-demo paths and placeholder traffic hooks must be adapted before host validation or real use.

Run the implemented host checks with:

uv run dploydb doctor --config /absolute/path/to/dploydb.yaml
uv run dploydb doctor --config /absolute/path/to/dploydb.yaml --deep

Normal mode checks configuration, required paths and executables, Docker and Compose CLI availability, candidate-port availability, lock ownership, durable operation state, and bounded read-only SQLite quick_check and foreign_key_check results. Deep mode additionally runs SQLite integrity_check, cleaned-up write probes, disk-space checks, Docker daemon inspection, and Compose service validation. When remote storage is disabled, both modes report it as skipped. When enabled, normal mode validates its runtime credentials and client configuration; deep mode also performs one bounded, read-only, prefix-scoped bucket access probe. Migration execution, application health, and traffic execution remain skipped. doctor never runs a developer migration as a diagnostic; the implemented internal rehearsal stage runs it only against a verified disposable copy inside a lock-tracked operation.

Inspect current state without creating, repairing, or deleting state files:

uv run dploydb status --config /absolute/path/to/dploydb.yaml
uv run dploydb status --config /absolute/path/to/dploydb.yaml --json

status exits 0 for coherent idle or active state and 60 for interrupted, stale, contradictory, corrupt, or recovery-required state. See IMPLEMENTATION_PLAN.md for the complete safety requirements and milestone order.

Create and independently reverify a local backup:

uv run dploydb backup --config /absolute/path/to/dploydb.yaml
uv run dploydb backup --config /absolute/path/to/dploydb.yaml --json
uv run dploydb verify backup_0123456789abcdef0123456789abcdef \
  --config /absolute/path/to/dploydb.yaml

Enable an S3-compatible target by naming environment variables rather than putting credentials in YAML. Cloudflare R2 uses its account endpoint and the auto region:

backup:
  local_directory: /srv/dploydb/backups/example-app
  keep_last: 10
  remote:
    enabled: true
    required: true
    provider: s3
    bucket: example-backups
    prefix: dploydb/example-app
    region_name: auto
    endpoint_url_env: DPLOYDB_S3_ENDPOINT_URL
    access_key_env: DPLOYDB_S3_ACCESS_KEY_ID
    secret_key_env: DPLOYDB_S3_SECRET_ACCESS_KEY
    timeout_seconds: 30
    max_attempts: 3

export DPLOYDB_S3_ENDPOINT_URL='https://ACCOUNT_ID.r2.cloudflarestorage.com'
export DPLOYDB_S3_ACCESS_KEY_ID='...'
export DPLOYDB_S3_SECRET_ACCESS_KEY='...'
dploydb doctor --deep --config /absolute/path/to/dploydb.yaml
dploydb backup --upload --config /absolute/path/to/dploydb.yaml --json

Use an R2 S3 access-key pair with access limited to the selected bucket. An R2 API token is not used by DployDB's S3 adapter. Never commit credentials or pass them as command-line arguments. Uploaded database bytes are not considered committed until DployDB reads them back and verifies size and SHA-256, then publishes and rereads immutable metadata. Restore downloads to a private temporary file and repeats size, checksum, and SQLite verification. For AWS S3, set region_name to the bucket's AWS region instead of auto.

To validate another S3-compatible service without writing credentials to disk or command history, run the acceptance helper and answer its no-echo credential prompts. It uses a unique child prefix, proves upload/list/download/SQLite restore/delete, and removes only the objects it created:

.venv/bin/python scripts/verify_s3_compatibility.py

The configured backup directory must be owned privately with mode 0700 when it already exists. Backup database and metadata files are written with mode 0600; metadata is published last and is the success marker. verify accepts only committed backup IDs. Manual restore accepts a protected release ID rather than a raw backup ID. After a release and its active pointer are durable, retention keeps the newest keep_last unprotected backups and additionally preserves every rehearsal and final backup referenced by the active and immediately previous releases, both locally and remotely.

The rehearsal and candidate lifecycle APIs remain internal implementation stages of deploy. A configured migration command must use database.path_env for its database target and must not hard-code the production path or perform unrelated production side effects; DployDB does not claim to sandbox an arbitrary developer-supplied executable.

• First production setup
• Security model and trust boundaries
• Supported scope, rollback boundary, and post-traffic data-loss risk
• Nginx maintenance and fixed-port activation hooks
• Uninstalling the CLI without deleting backups or evidence

DployDB follows Semantic Versioning. Compatible 0.1.x releases contain Alpha fixes; later 0.x minor releases may make documented breaking changes. 0.9.0 is reserved for Beta, 1.0.0rc1 for the first release candidate, and 1.0.0 for Stable. Durable state is never silently guessed or rewritten: an upgrade must provide a tested migration or stop with an exact safe action.

Promotion is based on real deployment, failure-drill, recovery, and soak-time evidence—not a calendar date. The exact gates and release procedure are in RELEASING.md, and user-visible changes are recorded in CHANGELOG.md.

DployDB is licensed under the Apache License 2.0, copyright 2026 RecursiveWay. Bug reports and pull requests are welcome under CONTRIBUTING.md and the community conduct policy. Report vulnerabilities privately as described in SECURITY.md.