Licensing
Free in production. One line you cannot cross.
TessariDB is licensed under the Business Source License 1.1. Production use is free — including inside a commercial company, and including inside a product you sell. There is one restriction, and it exists to stop a single thing: somebody reselling this database as their own service.
Free, with nothing to sign
Running it in production
Behind your product, your API, your internal systems. Whether or not the company makes money, and whether or not the thing it powers is sold.
Building a product on it
Ship it inside a commercial application, embed it, sell what you built. The licence reaches the database, not your code.
Reading, forking, modifying
The source is there to be read and changed. Nothing here asks you to send changes back, and nothing stops you keeping them.
Evaluating and developing
Testing, prototyping, benchmarking, CI, staging. Everything before production is covered by the same grant as production.
The one restriction
You may not provide TessariDB to third parties as a database service.
The licence defines that precisely, and the definition is narrow on purpose: a database service is a product, service, platform or commercial offering in which TessariDB, or a derivative of it, provides database functionality to parties other than your own employees and contractors, where those parties are able to create, manage or control namespaces, databases, tables or schemas.
Put another way: running TessariDB so that your application works is free, whoever your application’s customers are. Running TessariDB so that your customers get a database is the case that needs a commercial licence or written permission — licensing@tessaridb.com.
LICENSE; this is only where the line falls.- A SaaS whose backend happens to be TessariDB — free. Your users use your product; they do not get a database.
- An internal platform your own engineers build on — free. Employees and contractors are not third parties.
- An application you sell with TessariDB inside it — free, as long as the buyer is getting your application rather than a database to define schemas in.
- A hosted “TessariDB in the cloud” where customers create their own tables — a commercial licence. That is the case the restriction is written for.
If you are not sure which side of the line you are on, ask. The answer is usually one email long, and it is better given before you build than after.
What this licence is, precisely
BUSL 1.1 is source-available, not open source. Saying so plainly matters, because the distinction matters to the people who check — and a project that blurs it loses exactly those people. The source is public, readable and modifiable; what is restricted is one commercial use of it.
The licence text is what governs, and it ships in the repository. This page is a summary written to be understood rather than a substitute for it. On the Change Date recorded in that text, the licence converts to Apache 2.0.
The client and the protocol are Apache 2.0
The split is deliberate: the licence question only ever reaches the person operating the database, and never the person writing against it.
| What | Licence | Who it affects |
|---|---|---|
| The engine | BUSL-1.1 | Only somebody reselling it as a database service |
tessaridb-client | Apache 2.0 | Nobody — build on it freely |
| The wire protocol | Apache 2.0 | Nobody — write a client in any language |
So adding the client to an application is an ordinary Apache-2.0 dependency, and writing a client for a language that does not have one yet needs no permission at all.