lozick

Author business logic as functional, typed step-flows — and review the same definition as a node graph.

The workflow definition is both the code your server runs and the source the graph is drawn from, so the picture can never drift from the code.

📖 Docs: lozickjs.com · Getting Started · API reference

npm i lozick zod neverthrow

🔎 Looking for the lozick dev command? The graph viewer is a separate, dev-time package — install @lozickjs/cli (npm i -D @lozickjs/cli), then run npx lozick dev. The lozick package itself is the runtime library you import; it ships no CLI.

import { z } from "zod";
import { ok, err } from "neverthrow";
import { workflow, step, check, run } from "lozick";

const Cart = z.object({ items: z.number(), coupon: z.string().optional() });
const EmptyCart = z.object({ tag: z.literal("EmptyCart") });

const ensureNotEmpty = check({
  name: "ensureNotEmpty",
  input: Cart,
  errors: [EmptyCart],
  handler: ({ input }) =>
    input.items > 0 ? ok(true) : err({ tag: "EmptyCart" as const }),
});

export const placeOrder = workflow("placeOrder")
  .input(Cart)
  .check(ensureNotEmpty)
  .build();

const outcome = await run(placeOrder, { items: 2 });
// { ok: true, value: { items: 2 } }

Review it as a graph with the viewer — a separate dev-time package, @lozickjs/cli:

npm i -D @lozickjs/cli
npx lozick dev   # discovers *.flow.ts and serves the graph

lozick is just Zod + neverthrow + TypeScript — no server, no bundler.

License

MIT © Go Kobayashi