Brand.ai - Create a style guide & integrate with Sketch, Slack, & Gulp
Git Sketch Plugin - Version control for designers
Sketch Styler - Sets the most similar style to unstyled layers automatically
Anima App - Design, get feedback, convert to code, publish, iterate.
Sketch Repo - Collection of resources for anyone who uses Sketch
Marvel for Sketch - Sync, play and record prototypes in Sketch!