Quack: Turn DuckDB into a client-server database

DuckDB has released a beta of Quack, a protocol that turns the in-process analytical database into a client-server database management system, enabling multi-client access and remote querying. Announced by DuckDB co-founder Hannes Mühleisen at AI Council 2026, Quack supports the full DuckDB feature set over the wire and can handle a few thousand writes per second on an 8-CPU, 32 GB RAM server. The extension is available now and works with all DuckDB extensions, including DuckLake and community extensions.

Beta release available now Quack: Turn DuckDB into a client-server database The Quack protocol unlocks multi-client access for DuckDB, turning it into a general-purpose database system Quack protocol Client-server access · Beta release Introducing Quack Hannes Mühleisen introduced Quack at AI Council 2026. Watch his talk, the “Super-Secret Next Big Thing for DuckDB”. Architecture Clients Server Storage How it works Client-server setup You can take any two DuckDB processes on a network and turn them into client and server by using the Quack extension. The Quack protocol supports the full DuckDB feature set – over the wire. Optimized for performance We designed the Quack protocol for performance. We minimized the number of round trips, and ensured that the protocol can handle small updates and large batches just as well. Try Quack today Install and configure Quack in seconds Step 1 Install DuckDB Step 2 Launch Quack on the server Step 3 Connect from the client Frequently asked questions What is Quack? Quack allows DuckDB to connect to a DuckDB server through the quack: protocol. You can think of Quack as a Remote Procedure Call RPC protocol for DuckDB. Quack enables DuckDB instances to talk to each other, effectively turning DuckDB into a client-server database management system, where both the client and the server are DuckDB instances. Why is it called Quack? Mallard ducks communicate by quacking https://en.wikipedia.org/wiki/Duck Communication , so it's only fair that DuckDB instances communicate through the protocol quack . When should I use Quack? Quack can be beneficial in a number of scenarios, including the following: - You need concurrent read-write access to the same DuckDB database. - Your data is on a server and you want to move the computation as close to the data as possible. - You have a powerful server that can process the data but would like to see the results on your local computer. - And many more – we are excited to see what the community comes up with. Can I use DuckDB with Quack for transactional OLTP workloads? Yes. DuckDB with Quack can handle a few thousand writes per second on a server with 8 CPUs and 32 GB RAM. See the benchmarks in our announcement blog post https://duckdb.org/2026/05/12/quack-remote-protocol . Can I still run DuckDB as an in-process database? Yes, DuckDB as an in-process database will continue working just as it did before, and we will treat the in-process deployment model as a first-class citizen in the DuckDB ecosystem. Quack in the DuckDB ecosystem Client-server DuckDB Quack turns DuckDB into a client-server database for multi-writer and remote access. DuckLake server Quack supports querying DuckLake and other data lake formats. Community extensions Quack works with all DuckDB extensions, including the Community Extension ecosystem.