Nova

A general-purpose language built around algebraic effects, static contracts, and AI-first ergonomics.

Status: Bootstrap. Nova is in active early development. The compiler works, the standard library is partial, breaking changes happen weekly. Do not use in production.

What makes it different

Effects in signatures. Network, I/O, time, randomness, mutation — every side effect declared in the type. No hidden control flow, no surprise await.
Contracts as first-class. requires / ensures / invariant checked statically (SMT) when possible, at runtime in debug, zero-cost in release.
AI-first ergonomics. Designed for the era where LLMs write 50–80% of code: explicit signatures, locality, compiler errors as a learning signal.
M:N runtime. Go-style fibers with work-stealing scheduler. Managed by default (Boehm GC today, concurrent GC planned), realtime nogc for hot paths.

A taste

fn fetch_user(id u64) Result[User, NotFound]
    requires id > 0
    ensures result is Ok(u) implies u.id == id
    uses Db, Log
{
    log("fetching user", id)
    match db.find_user(id) {
        Some(u) -> Ok(u)
        None    -> Err(NotFound)
    }
}

Effects (Db, Log) and a postcondition right in the signature — the caller knows exactly what this function does and what to expect back.

Where to go

Source on GitHub — compiler, stdlib, tests, spec
Language specification — design decisions (D-blocks), grammar, open questions
Roadmap — current and historical plans
Contact: hello@nv-lang.org · Security: security@nv-lang.org