Terms, Types and Contexts are well-scoped.
- POPLMark: https://www.seas.upenn.edu/~plclub/poplmark/
- alan-j-hu/STLC: https://github.com/alan-j-hu/STLC
- sstucki/system-f-agda: https://github.com/sstucki/system-f-agda
- Jesper's 1001 Representations of Syntax with Binding: https://jesper.sikanda.be/posts/1001-syntax-representations.html
- Lysxia/system-F: https://github.com/Lysxia/system-F