Git Sketch Plugin - Version control for designers
CALCONIC_ - Build & add interactive calculators to your website! Choose from more than 50 premade calculators or build your own from scratch. No coding required. Free plan available. Zapier Integration. Publish Anywhere.
Anima App - Design, get feedback, convert to code, publish, iterate.
NI AWR Design Environment - NI AWR Design Environment is a circuit design and simulation solution.
Marvel for Sketch - Sync, play and record prototypes in Sketch!
Mapnik - Mapnik is a Free Toolkit for developing mapping applications.