Dagster 1.13.25 Speeds Declarative Automation for Partitioned Assets

Dagster shipped 1.13.25 on October 1, 2026, with core and libraries released together as 1.13.25 / 0.29.25. The change most operators will notice: declarative automation for partitioned assets evaluates faster when the asset has a long materialization history. The release notes and downloads are on the GitHub release page.

Automation policies fire off the materialization history of partitioned assets. That history grows without bound for daily and hourly partitions, and evaluation cost grew with it. This release improves that performance directly. If you backfill by automation instead of cron, this is the headline change.

No new configuration surface is documented for it. It reads as an internal performance fix, which is the right shape for a patch release.

The dagster-prefect Pipes clients are likely the second most impactful change. They now read messages through Prefect’s logs API by default. Previously a Pipes session needed a shared filesystem or bucket between the orchestrating and executed process. That requirement is gone.

The tradeoff: flows and tasks that open a Pipes session must pass message_writer=PipesPrefectLogsMessageWriter(). Existing Prefect deployments need no flow changes, but the session opening code does. If you skip that argument, you will find out at runtime rather than at deploy time.

dagster-aws ECS run launcher users can now resume run workers. That means max_resume_run_attempts can be set above 0 on ECS deployments. Before this release, run monitoring could detect a dead worker but ECS had no resumption path, so it behaved like an attempt floor of zero. Kubernetes deployments already had this; ECS gets parity.

Two bugfixes touch the dbt integration:

  • A dbt Fusion issue where models with no ref() or source() calls were silently dropped from asset selection, including in DbtProjectComponent. Silent asset selection misses are the worst kind, since they surface downstream as gaps rather than errors.
  • An AttributeError: module 'dbt' has no attribute 'contracts' raised when a local file named dbt.py shadowed the module in dg plus integrations dbt manage-manifest and dagster-cloud ci manage-state.

The docs also gained a dbt Fusion page. The remaining UI fixes, pagination on the Newer control and the new mobile layout, matter to daily users but not to pipelines, so they are listed mostly for completeness.

This is not a prerelease. Core is 1.13.25; the libraries move to 0.29.25 in lockstep.