Dagster is a cloud-native data orchestration platform that helps engineers declare, run, and observe data assets as Python-first constructs. It provides a declarative programming model where assets and pipeline logic are authored as Python functions, then scheduled, tested, and deployed from local development through production. Dagster includes integrated lineage, observability, and testability, plus a growing library of integrations with popular data tools, enabling teams to reliably maintain and monitor data pipelines at scale. The project is open-source (Apache 2.0) and is complemented by a commercial managed offering for teams that need hosted orchestration and enterprise features.