This directory contains the licence which applies to all material in the LumoSQL project. Licenses can be a confusing topic, but LumoSQL makes it easy.

The MIT license covers the source tree for LumoSQL. When you start LumoSQL development, the LumoSQL build tool pulls in code from other projects such as SQLite and LMDB and combines them to produce binaries in the build/ directory. LumoSQL does not pull code from projects with licenses incompatible with the MIT license. The binaries produced by LumoSQL can be used for any purpose. If you enable the libdb backend you need to include a notice of where to find the source, as explained below.

MIT Licence

The MIT Licence applies to all files in this project with two exceptions listed below. The MIT licence is the most-widely used Open Source licence, including by some of the world's largest companies. The MIT licence grants everyone the right to use the code for any purpose under copyright law. Every LumoSQL file should have a copyright statement at the top and also a Software Package Data Exchange machine-readable header. Even if a file does not have these statements at the top, the MIT licence still applies to all files in the LumoSQL source tree including files that are not clearly code, such as configuration or input data.

The LumoSQL Documentation has source files in /doc in the LumoSQL source tree and therefore also covered by the MIT licence. Documentation-specific licences do exist and they do have certain advantages. If the MIT licence ever becomes a problem for LumoSQL documentation we will adopt one of these licenses.

To even further avoid potential misunderstanding, we maintain the site license.lumosql.org with the full text of the MIT Licence.

Exception for academic papers

We do include some academic papers in full in the source tree under /references. Evidently, these papers are copyright their respective authors and universities as listed.

Optional except for the libdb backend - BSD license

A target with the libdb backend, such as 3.53.2+libdb-2026.10.1, links libdb statically into the SQLite library and shell. libdb requires BSD-style notices from the University of California, Harvard University and INRIA, see libdb-LICENSE.txt.

If you distribute a LumoSQL binary with libdb, you have to tell users this:

The LumoSQL source is at https://lumosql.org/src/lumosql and the libdb source at https://github.com/berkeleydb/libdb.