Rollouts

Rollouts are SurrealKit's migration system for shared and production databases. Rather than immediately pushing all changes (as Sync does), Rollouts generate a reviewed manifest and apply it in two phases: an expand phase that adds new definitions without breaking existing consumers, and a contract phase that removes old ones after your application has been updated. Deploying schema and application changes separately means no downtime.

The phased migration model

A complete rollout has three stages:

1. Start: applies non-destructive changes: adding tables, fields, indexes, and access methods that new application code will use. The old application code continues to work alongside the new definitions.

2. App cutover: you deploy the new version of your application. Both old and new application code remain compatible with the database during this window.

3. Complete: applies destructive changes: removing legacy tables, fields, or indexes that are no longer needed. Only run this after the new application version is stable.

Command workflow

For an existing database: baseline first

If you are adopting SurrealKit on a database that already exists, capture a baseline before planning any rollout:

surrealkit rollout baseline --user root --pass secret

This reads the current database schema and writes snapshot files to database/snapshots/. Future plans diff against this baseline. You only need to run this once.

Plan a rollout

After editing your schema files, plan a rollout:

surrealkit rollout plan --name add_customer_indexes

SurrealKit computes the diff between the current snapshot and your schema files, then generates a timestamped manifest in database/rollouts/:

database/rollouts/20260302153045__add_customer_indexes.toml

Review this file before proceeding. It lists each step, the SQL it will execute, and which phase (start or complete) it belongs to. Commit it to your repository alongside your schema changes.

Start the rollout

surrealkit rollout start 20260302153045__add_customer_indexes --user root --pass secret

This applies all start-phase steps. SurrealKit records resumable state in the __rollout metadata table, so if the process is interrupted it can pick up where it left off. Only one rollout can be in progress at a time; concurrent starts are blocked.

Deploy your application

After start completes, deploy the new version of your application. At this point both the old and new schema definitions coexist in the database.

Complete the rollout

Once the new application version is healthy:

surrealkit rollout complete 20260302153045__add_customer_indexes --user root --pass secret

This applies all complete-phase steps (removing legacy definitions) and marks the rollout as done.

Rollback

If something goes wrong after start but before complete, you can undo the start-phase changes:

surrealkit rollout rollback 20260302153045__add_customer_indexes --user root --pass secret

Rollback reverses what start applied. It is not available after complete has run, so verify your application is working correctly before calling complete.

Other commands

status

Inspect the state of rollouts stored in the database:

surrealkit rollout status --user root --pass secret

lint

Validate a manifest file without connecting to the database or applying anything:

surrealkit rollout lint 20260302153045__add_customer_indexes --user root --pass secret

This is useful in CI to catch manifest errors before they reach a shared environment.

Rollout state machine

Each rollout transitions through the following states, recorded in the __rollout table:

planned → running_start → ready_to_complete → completed
                       ↘
                        rolled_back

Artifacts

Next steps

• Template Variables: parameterise schema files for different environments

• Testing: validate schema and permissions before promoting a rollout