App Design and Architecture
SEGUL is available as a GUI, CLI, and a library. All three versions share the same core functionalities. The SEGUL core library is written in Rust, a systems programming language that is known for its speed, memory safety, and parallelism. The GUI layer uses in Flutter and is written in Dart. The CLI is wrapped around the Rust library and is written in Rust.
Repository Structure
We uses multi-repository structure to separate the GUI and SEGUL core library. The CLI is part of the SEGUL core library. The repository can be found in the following links:
Connecting the GUI and CLI
The GUI and CLI communicate through a bridge. The bridge is a Rust library that wraps the SEGUL core library. THe rust library can communicate with the GUI through the C-FFI (Foreign Function Interface) feature. We simplify creating the bridge by using the amazing Flutter Rust Bridge (FRB). SEGUL use the version 2 of FRB.
If we were to redesign the repository structure, we would adopt a monorepo approach where the library, CLI, and GUI are all contained within a single repository. We could leverage the Rust workspace feature to manage both the library and CLI. The Rust bridge for the GUI could be managed as a separate package. This approach has been implemented in our NAHPU app, which serves as a digital field catalog for natural history collections.