Skip to main content
Version: 2.0 prerelease

Embedded to Server Migration

This guide is for teams already running Durable Workflow v2 inside a Laravel application and moving new workflow traffic to the standalone server. If the application is still on v1, start with Migrating to 2.0 and keep existing v1 runs on the v1 engine until they finish.

The migration is an adoption path, not an in-place database move. The standalone server owns new control-plane starts, durable history, schedules, worker registrations, and task delivery over HTTP. Your application workers continue to own workflow and activity code.

Current Boundary

Supported today:

  • Start new workflows through the server control-plane API or CLI.
  • Register PHP, Python, or custom HTTP workers against the server.
  • Poll and complete workflow and activity tasks through the worker protocol.
  • Import eligible embedded v2 history-export bundles into the server as server-managed workflow state.
  • Export closed-run history bundles from embedded v2 or server v2 for audit, debugging, and archival handoff.
  • Observe server-managed workflows through the server API, CLI, and SDK surfaces that read server state. Waterline keeps reading the embedded Laravel app's own durable state — it is not part of the standalone-server distribution and does not call out to the server.

Not supported as an automatic operation today:

  • Moving v1 runs into the server.
  • Replaying v1 history with non-PHP workers.

Plan the cutover so v1 runs drain where they started. Embedded v2 runs may either drain in place or move through the import workflow below.

Deployment Mode Contract

For the frozen embedded-vs-service comparison, see Deployment Modes. This migration guide adds three cutover-specific rules on top of that shared contract:

  • Existing embedded runs keep executing where they started.
  • New server-managed runs use stable type keys, namespace names, task queues, and payload codecs from the first cutover.
  • Signals, queries, updates, repair, cancel, terminate, and archive must keep routing to the runtime that owns the target run.

Cutover Invariants

Keep these rules true throughout the migration:

  • Configure the server as an explicit remote dependency: set the base URL, namespace, task queue, and auth material directly instead of inferring them from Laravel app-local settings.
  • Keep workflow ids, run-targeting rules, workflow/activity type keys, payload codec, and compatibility markers stable across both runtimes.
  • Route signals, queries, updates, repair, cancel, terminate, and archive to the same runtime that owns the target run.
  • Before importing an embedded run, pause embedded workers long enough to export a quiesced bundle with no leased workflow/activity task and no running activity attempt.
  • Treat language neutrality as part of the migration contract: server-managed workflows should use stable aliases and a codec such as avro, not PHP-only class names or payload formats.

Phase A: Prepare Embedded v2

Before deploying the server, make the embedded app use language-neutral contracts. This reduces the amount of code that changes during cutover.

  1. Define stable workflow and activity type keys.

    // config/workflows.php
    'v2' => [
    'types' => [
    'workflows' => [
    'orders.process' => App\Workflows\ProcessOrderWorkflow::class,
    ],
    'activities' => [
    'orders.reserve-inventory' => App\Activities\ReserveInventory::class,
    'orders.capture-payment' => App\Activities\CapturePayment::class,
    ],
    ],
    ],
  2. Use those keys at every external boundary.

    Server clients send workflow_type: "orders.process", and workers register supported_workflow_types / supported_activity_types with those same strings. Do not expose PHP FQCNs as the durable public contract.

  3. Use the language-neutral payload codec.

    // config/workflows.php
    'serializer' => 'avro',

    Keep legacy PHP codecs only while finishing old PHP-only runs. New server-managed workflows should use avro.

  4. Pick namespace and task queue names.

    Choose names you can keep stable across embedded, server, and cloud:

    export DURABLE_WORKFLOW_NAMESPACE=production
    export DURABLE_WORKFLOW_TASK_QUEUE=orders
  5. Decide whether compatibility markers are needed.

    A single-fleet deployment can leave compatibility unset. The standard v2 rollout mechanics (canary, drain, rollback, replay-debug) all operate inside one stable v2 contract — there is no "mixed-fleet v2" adoption lane. If a build-skew window does open during the embedded to server cutover, set DW_V2_CURRENT_COMPATIBILITY and DW_V2_SUPPORTED_COMPATIBILITIES before the cutover so a new build does not claim runs from an incompatible build during that window.

Phase B: Deploy the Server Beside Embedded

Run the server as a new runtime target while the Laravel app continues handling existing embedded runs.

git clone https://github.com/durable-workflow/server.git
cd server
cp .env.example .env
docker compose up -d

For local development you may set DW_AUTH_DRIVER=none. For shared environments, use role-scoped credentials:

DW_AUTH_DRIVER=token
DW_WORKER_TOKEN=worker-secret
DW_OPERATOR_TOKEN=operator-secret
DW_ADMIN_TOKEN=admin-secret

Verify discovery and create the namespace:

export SERVER=http://localhost:8080
export ADMIN_TOKEN=admin-secret
export OPERATOR_TOKEN=operator-secret

curl "$SERVER/api/health"

curl "$SERVER/api/cluster/info" \
-H "Authorization: Bearer $OPERATOR_TOKEN"

curl -X POST "$SERVER/api/namespaces" \
-H "Authorization: Bearer $ADMIN_TOKEN" \
-H "X-Durable-Workflow-Control-Plane-Version: 2" \
-H "Content-Type: application/json" \
-d '{"name":"production","description":"Production workflows","retention_days":30}'

The server rejects control-plane requests without X-Durable-Workflow-Control-Plane-Version: 2; workers use the separate X-Durable-Workflow-Protocol-Version: 1.0 header.

Phase C: Connect Workers

Workers must register before polling. The registration advertises runtime, task queue, and the type keys the worker can execute.

export WORKER_TOKEN=worker-secret

curl -X POST "$SERVER/api/worker/register" \
-H "Authorization: Bearer $WORKER_TOKEN" \
-H "X-Namespace: production" \
-H "X-Durable-Workflow-Protocol-Version: 1.0" \
-H "Content-Type: application/json" \
-d '{
"worker_id": "orders-php-1",
"task_queue": "orders",
"runtime": "php",
"sdk_version": "2.0.0-alpha",
"supported_workflow_types": ["orders.process"],
"supported_activity_types": [
"orders.reserve-inventory",
"orders.capture-payment"
],
"max_concurrent_workflow_tasks": 10,
"max_concurrent_activity_tasks": 50
}'

Then run workers in server mode for the same namespace and task queue. Python workers follow the same registration and poll contract through the Python SDK. Custom workers can use the Worker Protocol directly.

Check visibility before cutover:

curl "$SERVER/api/workers" \
-H "Authorization: Bearer $OPERATOR_TOKEN" \
-H "X-Namespace: production" \
-H "X-Durable-Workflow-Control-Plane-Version: 2"

curl "$SERVER/api/task-queues/orders" \
-H "Authorization: Bearer $OPERATOR_TOKEN" \
-H "X-Namespace: production" \
-H "X-Durable-Workflow-Control-Plane-Version: 2"

Phase D: Route New Starts to the Server

Cut over one workflow family at a time. Keep the embedded app and queue workers running for old runs until they drain.

Start a shadow workflow first:

curl -X POST "$SERVER/api/workflows" \
-H "Authorization: Bearer $OPERATOR_TOKEN" \
-H "X-Namespace: production" \
-H "X-Durable-Workflow-Control-Plane-Version: 2" \
-H "Content-Type: application/json" \
-d '{
"workflow_id": "orders-shadow-1001",
"workflow_type": "orders.process",
"task_queue": "orders",
"input": [{"order_id":"1001","mode":"shadow"}]
}'

Watch the run:

curl "$SERVER/api/workflows/orders-shadow-1001" \
-H "Authorization: Bearer $OPERATOR_TOKEN" \
-H "X-Namespace: production" \
-H "X-Durable-Workflow-Control-Plane-Version: 2"

After the shadow path works, move the production caller from WorkflowStub::start() to the server client, CLI, or direct HTTP API. Leave signals, queries, updates, cancel, and terminate routed to the same runtime that started the workflow. A workflow started embedded should receive embedded commands; a workflow started on the server should receive server control-plane commands.

Phase E: Import Eligible Embedded v2 Runs

Use history export as the import format. The embedded runtime remains the source of truth for the bundle; the server verifies it, writes durable rows inside one transaction, and rebuilds server projections from those rows.

Eligibility:

  • The bundle schema must be durable-workflow.v2.history-export with schema_version: 1.
  • The source run must be embedded v2 and the export must carry workflow.source_runtime: "embedded". v1 history remains out of scope.
  • A non-terminal run must be the current embedded run.
  • A terminal run must have history_complete: true.
  • Redacted bundles are rejected.
  • Leased workflow tasks, leased activity tasks, and running activity attempts are rejected. Pause workers or let leases expire, then export again.

Import source-of-truth rules:

  • history_events are copied as the authoritative replay and audit log.
  • Workflow identity, payloads, commands, signals, updates, tasks, activity executions, timers, failures, and lineage links are reconstructed from the bundle.
  • Server summary, wait, timer, timeline, and lineage projections are rebuilt after import. Projection rows are not the import authority.
  • Pending workflow tasks remain claimable by compatible server workers.
  • Pending activity executions and ready activity tasks remain claimable by compatible server activity workers.
  • Pending timers keep their fire_at timestamp and are visible to server timer repair/recovery.

Failure and rollback:

  • Import is all-or-nothing in one database transaction.
  • If the process exits or validation fails before commit, no partial run state remains on the server.
  • Retrying the same bundle is idempotent by run_id and dedupe_key.
  • If a different server run already owns the same run_id, import is rejected.

Visibility and audit:

  • Imported runs expose engine_source: embedded_v2_import in server list/detail views.
  • The durable run row records import_source=embedded_v2, import_id, import_dedupe_key, import_contract_version, and imported_at.

Operator workflow:

For embedded v2 runs:

php artisan workflow:v2:history-export order-123 \
--output=storage/workflow-history/order-123.json \
--pretty

Dry-run the import on the server:

php artisan workflow:v2:history-import storage/workflow-history/order-123.json \
--namespace=production \
--dry-run \
--json

Import the bundle:

php artisan workflow:v2:history-import storage/workflow-history/order-123.json \
--namespace=production \
--import-id=orders-cutover-2026-05-05

Or call the HTTP operator endpoint:

curl -X POST "$SERVER/api/workflows/import/embedded-v2" \
-H "Authorization: Bearer $ADMIN_TOKEN" \
-H "X-Namespace: production" \
-H "X-Durable-Workflow-Control-Plane-Version: 2" \
-H "Content-Type: application/json" \
--data-binary @order-123-import-request.json

where order-123-import-request.json is:

{
"import_id": "orders-cutover-2026-05-05",
"bundle": {
"schema": "durable-workflow.v2.history-export",
"schema_version": 1,
"workflow": {
"source_runtime": "embedded"
}
}
}

The bundle object above is abbreviated; pass the complete workflow:v2:history-export JSON document.

For server-managed runs that you only need to preserve or audit:

curl "$SERVER/api/workflows/order-123/runs/$RUN_ID/history/export" \
-H "Authorization: Bearer $OPERATOR_TOKEN" \
-H "X-Namespace: production" \
-H "X-Durable-Workflow-Control-Plane-Version: 2" \
> order-123-history.json

Archive terminal server runs after export when you want to keep them out of retention pruning:

curl -X POST "$SERVER/api/workflows/order-123/archive" \
-H "Authorization: Bearer $OPERATOR_TOKEN" \
-H "X-Namespace: production" \
-H "X-Durable-Workflow-Control-Plane-Version: 2" \
-H "Content-Type: application/json" \
-d '{"reason":"history exported to archive storage"}'

Phase F: Add Polyglot Workers

Once a workflow family runs through the server, add Python or custom workers by registering the same namespace, task queue, and type keys. Keep payloads in avro and keep activity inputs and outputs language-neutral: arrays, objects, strings, numbers, booleans, and nulls.

For Python, use the Python SDK guide. For direct HTTP implementations, use the worker protocol reference.

Cutover Checklist

  • v1 runs are drained or intentionally left on the v1 engine.
  • Embedded v2 uses stable type keys, not PHP FQCNs, at external boundaries.
  • New v2 workflows use the avro codec.
  • Server /api/health and /api/cluster/info pass from the deployment network.
  • Target namespace exists on the server.
  • Workers register with the expected task queue and supported type keys.
  • A shadow workflow starts, is claimed by a worker, and reaches the expected state.
  • Operators can list workflows, inspect task queues, and view worker registrations.
  • Old embedded starters are paused or moved so duplicate business keys do not start in both runtimes.
  • Embedded v2 runs selected for import are exported from a quiesced embedded runtime and pass workflow:v2:history-import --dry-run.
  • Imported runs show engine_source: embedded_v2_import and the expected import_id in server detail/list surfaces.
  • Closed old runs that only need retention are exported to durable storage.

Troubleshooting

SymptomLikely causeFix
missing_control_plane_versionClient called a control-plane route without the v2 headerSend X-Durable-Workflow-Control-Plane-Version: 2
missing_protocol_versionWorker called a worker route without the worker protocol headerSend X-Durable-Workflow-Protocol-Version: 1.0
namespace_not_foundThe namespace has not been created on the serverCreate it with POST /api/namespaces
Worker polls return no taskTask queue, type key, namespace, or compatibility marker does not matchCompare workflow start payload, worker registration, and task queue visibility
Payload cannot be decoded by a non-PHP workerA legacy PHP serializer was used for new v2 workMove new starts to avro; drain legacy-codec runs on PHP
Old workflow does not respond to server signal/query/updateThe run was started in embedded modeSend commands through the embedded app until that run finishes
Import rejects tasks.leased_task_presentThe embedded export captured a leased taskPause embedded workers, wait for leases to release or complete, then export again
Import returns already_importedThe same run_id and dedupe_key are already present on the serverTreat the retry as successful and inspect the server run
Imported run is visible but not claimedWorker type key, task queue, namespace, or compatibility marker does not match the imported rowCompare the import report, run detail, and worker registration