Ted (Timing-Explicit Description, aka The Teddy Bear Language) is a systems programming language with explicit logical time and deterministic concurrency. Hardware modeling is a first-class library built on the same semantics.

Timing stays an explicit effect: most code is ordinary and compiles to tight CPU code; timed code opts in to @ and event sources when you need scheduling or simulation.

mod blink {
 out led: bit,
 loop {
 led = !led @ +500ms; // schedule the next toggle 500ms later
 }
}

• Core Ted - ordinary functions, data structures, and loops with no scheduler overhead
• Timed Ted - @, event handlers, and temporal values executed on a deterministic scheduler

• Explicit time - Scheduled updates x = v @ +delta and history reads x @ -delta for temporal values
• Deterministic concurrency - Same input, same schedule, designed for reproducible runs and replayable debugging
• Hardware as a library - Ports, edge events, and waveforms are conventions built on the timed core
• Rust-like - Familiar syntax for systems programmers

# Build
cargo build --workspace
# Check a source file
cargo run -p ted-cli -- check examples/blink.ted
# Compile to a native executable (prototype backend)
cargo run -p ted-cli -- compile examples/hello.ted --emit exe -o ./hello
./hello
# Run tests
cargo test --workspace

Note: the prototype backend currently only supports literal print(...) calls.

Build and view the docs locally:

mdbook serve docs/

Or read online at docs.ted-lang.org.

crates/
├── ted-ir # Shared IR utilities (spans, IDs)
├── ted-diagnostics # Error reporting
├── ted-lexer # Tokenization
├── ted-parser # AST and parsing
├── ted-codegen # Code generation backends
└── ted-cli # Command-line interface
docs/ # Language documentation (mdbook)
examples/ # Example Ted programs

See AGENTS.md for build instructions and coding standards.

Ted is licensed under GPL-3.0.