**Eddi** is a graphically interactive editor for diagrams
consisting of several directed graphs and of (relational)
graph homomorphisms inbetween.

Diagrams can be constructed manually, and they can be extended by graph transformation steps:

- pushout of total graph homomorphisms
- pushout complement
- pushout of partial graph homomorphisms
- pullback of total graph homomorphisms
- pullback complement
- relational constructions

**Eddi** is still under development.

Wolfram Kahl