Lightweaver is an add-on for Blender by WuYin, built around light-driven color grading. It lets you create cinematic color variations directly from ray-traced lighting inside your scene. The workflow stays inside Blender, without exporting EXR files or switching to compositing software like Nuke.
The add-on works with both the Cycles and Eevee render engines. It is a published Blender Extension, distributed under the GPL license, and ships with documentation to help you get started.
Lightweaver targets artists who want to shape lighting and color inside Blender itself instead of moving output into an external editing or compositing tool. A demo video is available, and the developer's page provides further documentation and licensing details for individuals and studios of different sizes.