Szál

Szál (Hungarian: thread) — Workflow orchestration engine for Rust

Define steps, wire them into flows with branching, retry, and rollback — then execute sequentially, in parallel, or as a DAG. Part of the AGNOS ecosystem.

Quick start

[dependencies]
szal = "1"

Sequential flow

use szal::flow::{FlowDef, FlowMode};
use szal::step::StepDef;

let mut flow = FlowDef::new("deploy-pipeline", FlowMode::Sequential);
flow.add_step(StepDef::new("build").with_timeout(60_000));
flow.add_step(StepDef::new("test").with_retries(2, 1_000));
flow.add_step(StepDef::new("deploy").with_rollback());
flow.validate().unwrap();

DAG workflow

use szal::flow::{FlowDef, FlowMode};
use szal::step::StepDef;

let build = StepDef::new("build");
let unit_test = StepDef::new("unit-test").depends_on(build.id);
let integ_test = StepDef::new("integ-test").depends_on(build.id);
let deploy = StepDef::new("deploy")
    .depends_on(unit_test.id)
    .depends_on(integ_test.id);

let mut flow = FlowDef::new("ci-cd", FlowMode::Dag);
flow.add_step(build);
flow.add_step(unit_test);
flow.add_step(integ_test);
flow.add_step(deploy);
flow.validate().unwrap(); // cycle detection + dependency validation

State machine

use szal::state::WorkflowState;

let state = WorkflowState::Created;
assert!(state.valid_transition(&WorkflowState::Running));
assert!(!state.is_terminal());

Modules

Execution modes

Roadmap

License

AGPL-3.0-only