A data warehouse without the migration.

Yes. Query engines can read open table formats where they already sit, so the warehouse becomes a layer over your storage rather than a destination you copy into. Ward reads Iceberg, Delta and Parquet in place and federates to the databases and warehouses you already run, on read-only credentials scoped to tables you name. What you get is a queryable warehouse with shared metric definitions on top of it, without a lift and shift, a cutover window, or a second copy of anything.

A zero-migration data warehouse is one where the data stays in its existing storage and systems, and the warehouse layer queries it where it is. The pattern is usually built on open table formats like Apache Iceberg and Delta Lake plus federated query to operational sources. The trade is real: federation can be slower than a local copy for heavy workloads, so most teams federate by default and ingest the few tables that justify it.

Cloudera fits the case where the data cannot leave a specific place. It is a data platform you deploy and operate where your data lives, including on-premises and in controlled regions, and it works in open formats rather than locking you into a vendor warehouse. The distinction against Ward is platform versus layer. With Cloudera you run the platform, which is the point of it when residency or on-premises is a hard constraint. With Ward there is nothing to install: it reads the systems you already run and the warehouse exists on top of them.

ETL copies data on a schedule into a warehouse, and every query then runs against the copy. Federated query leaves the data where it is and pushes the query out to each source at read time. ETL gives you speed and a stable snapshot at the cost of a pipeline to maintain, a copy to secure, and freshness measured in hours. Federation gives you current data and nothing to move, at the cost of latency on heavy joins and a dependency on the source being reachable. Most production stacks end up with both, chosen per source rather than decided once.

Plan in quarters rather than weeks for a full migration. Moving the bytes is rarely the hard part. The schedule goes on rebuilding the metric definitions, because almost nobody has written down what a metric means, only the reports that use it, and every one of those has to be reproduced and reconciled against the old system before anyone will trust the new one. That reconstruction is the reason a warehouse project outlives the quarter it was scoped in.

Not by default. Ward connects on read-only credentials scoped to the tables you name and reads your lake and warehouses in place. Query results and cached intermediates live in the Ward tenant under a retention policy you set, because a warehouse that recomputes everything from source on every question is not a warehouse. Ingest is available per source where federation is too slow for a workload, and it is a choice you make rather than a default. Writes are off until you grant them per table.