BUGGIFY

BUGGIFY is Marionette's fault-injection hook. Marionette decides whether a hook fires; user code owns what that means for the domain.

The API lives on Env:

if (try env.buggify(.drop_packet, .percent(20))) {
    return error.PacketDropped;
}

Production envs should construct Env with buggify disabled, so env.buggify always returns false. Simulation envs returned by world.simulate draw through env.io() into the world's single PRNG according to the supplied BuggifyRate and record buggify hook=<name> rate=<n>/<d> roll=<value> fired=<bool> in the trace. Invalid runtime rates return error.InvalidRate before any random draw or hook trace event.

Use buggify for domain-specific fault points such as dropping a packet, delaying a response, returning a write error, or forcing a retry. Marionette controls the random choice, trace event, and production behavior.

Worked Fault Hook

pub fn sendPacket(env: anytype, packet_id: u64) !void {
    const io = env.io();
    var source: std.Random.IoSource = .{ .io = io };
    const latency_ns = source.interface().intRangeLessThan(u64, 0, 1_000);
    try std.Io.sleep(io, .fromNanoseconds(latency_ns), .awake);

    if (try env.buggify(.drop_packet, .percent(20))) {
        return SendError.PacketDropped;
    }

    _ = packet_id;
}