Zap Programming Language

Systems programming that doesn't get in your way.

You want predictable performance. No GC pauses. Real enums. Error handling that doesn't look like noise.

Zap is a systems language built for developers who know Go or are ready to step into systems programming. ARC memory model, LLVM backend, modern syntax. Write low-level software without low-level frustration.

Discord · Roadmap · Documentation

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Why Zap?

Warning

Early alpha — not everything is implemented yet.

Problem	Zap's answer
GC pauses & unpredictable latency	ARC, memory freed deterministically
No real enums	Enums with exhaustive pattern matching
Verbose error handling	Failable functions
Limited generics	Full static generics
Concise conditional expressions	Ternary operator ?:
Single-platform compilers	LLVM: x86, ARM, RISC-V, WASM, embedded
No lightweight concurrency	Fibers, like goroutines without the runtime cost
Hard to triage compiler errors at scale	Stable diagnostic codes (Pxxxx, Sxxxx, Wxxxx, Nxxxx) in CLI and LSP

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Cycles

If you know what ARC is, you probably also know that when two objects point to each other, ARC will never delete them even though they are not needed. Swift added weak to prevent this, we also added weak in Zap, but it often happens that you simply don't see that there is a cycle somewhere. Zap solves this problem thanks to its Cycle Collector, i.e. it is actually a garbage collector operating on objects causing the cycle, REST OF OBJECTS ARE NOT AFFECTED (cycle collector can be disabled if someone needs it!)

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Error Handling

Zap uses failable functions: functions that can fail declare it explicitly in their return type.

@error
enum MathError { DivisionByZero, Overflow }

fun divide(a: Int, b: Int) Int!MathError {
    if b == 0 { fail MathError.DivisionByZero; }
    return a / b;
}

fun main() Int {
    // propagate up with ?
    var x: Int = divide(10, 2)?;

    // fallback value
    var y: Int = divide(10, 0) or 0;

    // handle locally
    var z: Int = divide(10, 0) or err {
        return 1;
    };

    return 0;
}

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Documentation

Start here: docs/README.md

Highlights:

• Language guide: variables, functions, control flow, data structures, classes, memory
• Generics coverage: function/type generics, constraints (where), and compile-time iftype (see docs sections and tests)
• Diagnostic code reference: docs/diagnostic_codes.md

Contributing

Zap is in early alpha. Your feedback directly shapes the language.

• open issues
• discuss language design
• implement features
• improve diagnostics
• write documentation

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