Build safe, intelligent systems with Sailfin

An AI-native, systems-friendly programming language with effect types, ownership semantics, and first-class AI constructs.

curl -fsSL https://sailfin.dev/install.sh | sh
analyze.sfn
fn analyze(data: Dataset<Record>) -> Report ![io, model] {
    let cleaned = data
        .filter(|r| r.is_valid())
        .map(|r| normalize(r));

    model gpt4o = openai:"gpt-4o";

    let insights = prompt gpt4o ![model] {
        system "You are a data analyst."
        user "Summarize trends in: {{cleaned}}"
    };

    Report {
        data: cleaned,
        summary: insights,
    }
}

Built for

AI-Powered Services

Build production AI pipelines with type-safe model calls, structured prompts, and generation provenance tracking.

Systems Programming

Ownership semantics and native compilation via LLVM make Sailfin suitable for performance-critical infrastructure.

Secure Data Processing

PII and Secret wrapper types, plus capability-based security, enforce data handling policies at compile time.

CLI Tools & Automation

Concise syntax, fast compilation, and single-binary output make Sailfin ideal for developer tooling.

Ready to dive in?

Install Sailfin and build your first program in minutes.