Open Source Ada Projects

After the lessons, real codebases are the advanced textbook. The projects below are open source, active, and each teaches a different part of professional Ada — read their .ads specifications first, then the bodies.

Toolchain and Core

Project	What it is	Why study it
GNAT	The GCC Ada compiler front end	See how the language's own rules are implemented
Alire	The Ada package manager (written in Ada)	A real CLI application: command parsing, config, dependency graphs
GPRbuild	Multi-language build engine	Dependency-driven builds and the project-file model
ada_language_server	The LSP server powering Ada in VS Code and other editors	Compiler-adjacent engineering: parsing, queries, incremental analysis
SPARK toolset	Proof tools for the verified Ada subset	Where the contracts from the Contracts lesson become theorems

Libraries

Project	What it is	Why study it
AWS (Ada Web Server)	HTTP server framework and SOAP/WebSockets stack	API design at scale, tasking under load
GNATCOLL	GNAT Component Collection: files, processes, scripting, DB	The "standard-library-plus" — idiomatic package structure
GtkAda	GTK bindings for GUI applications	Large-scale C interop with tagged types and callbacks
Ada Drivers Library	Board-support and peripheral drivers for embedded MCUs	Representation clauses and real hardware access, portably written
Templates Parser	Template engine used by AWS	Text processing and generic design in production

Complete Applications

Project	What it is	Why study it
Ada Lua	Lua interpreter bindings and embedding in Ada	Scripting layer over a compiled core
Anet	Networking library (sockets, IPv4/IPv6)	Protocol layers expressed with discriminants and controlled types
AdaSAT	A SAT solver in SPARK	Algorithmically interesting AND machine-proved
GNAT Studio	AdaCore's IDE, itself written largely in Ada	A very large GUI Ada program — architecture in the wild

Browsing tip. Most of these live under the AdaCore GitHub organization, which also hosts the Alire crates index. Search a repo for is private to find its encapsulation boundaries, and for with Pre to see live contracts — two habits that make any Ada codebase readable fast.