Lektor consists of many interfaces that you can interface with through various different ways. Not just when developing plugins, but also from within the templates. This part of the documentation covers all those areas in detail.
Everything about Lektor's build system.
A support system for loading site specific variables.
Detailed information about Lektor's flat file tree database system.
The working environment for the build process.
Provides an introduction to the plugin system in Lektor.
Provides access to a project file.
The interface for extending the deployment process
Specific functionality added to the Jinja template environment by Lektor.
Some useful utilities for plugins.