v1.0.0-beta.16Desktop beta: macOS · Windows (untested) · What's new →

Watch your process run before it runs.

Open-source discrete-event simulator for BPMN. Draw the process, set times, resources and calendars, and replay every case over the diagram — with AS-IS vs TO-BE comparisons at 95% confidence. No account, no server.

▶ Open the app Quick start Coming from Bizagi? →

Apache-2.0Browser · Desktop · CLI · MCPSeeded & reproducible

Live replay examples/pedido · AS-IS · seed 42 Clock 08:00 Completed 0 WIP 0 Avg cycle —

Speed 1× Case token Waiting for a resource Pool slot busy 12/14completed / started

← swipe the diagram →

01 — Capabilities

One engine, four ways in.

The core has no dependencies, so the numbers are identical from a browser tab, a terminal or an agent.

/model

Model

BPMN editor on bpmn-js
XOR / OR / AND gateways
Timers, subprocesses, lanes
Validation on the diagram

/simulate

Simulate

Bizagi's four levels, as steps
13 BPSim distributions
Resource pools with costs
Weekly shift calendars

/analyze

Analyze

Bizagi-style result tables
Ranked bottlenecks
Replay over the diagram
CSV and XLSX export

/integrate

Integrate

lila run / compare for CI
MCP server, five tools
Portable .lila projects
Scenarios as plain JSON

02 — How it runs

Not one lucky number. Thirty replications.

Every run is seeded and replicated. Each replication drops into the distribution and the confidence interval tightens — same seed, same answer, every time.

L1Validation — every path reaches an end
L2Time — arrivals and processing times
L3Resources — pools, capacity, cost
L4Calendars — weekly shifts

Cycle time · min n 0/30 mean — 95% CI ± —

03 — Compare

AS-IS vs TO-BE, with the noise taken out.

Put scenarios side by side. Deltas that are significant at 95% get a marker; the rest you shouldn't bet on.

as-is to-be · 3 cashiers Δ · significant

Cycle time

−22%● yes

Queue at Take order

−70%● yes

Cashier utilization

−26 pp● yes

Cost per case

+7%○ no

Illustrative figures · run lila compare on examples/pedido for the real ones.

04 — Quick start

Three commands to a benchmark.

Clone, npm ci && npm run build, then validate, run and compare the restaurant example. Or hand the same engine to an agent over MCP.

webUse it in your browser, no install macDownload the macOS beta (Apple Silicon, not notarized) winDownload the Windows installer (x64 — unsigned and not tested on a real PC yet; SmartScreen will warn) docsRead the documentation

~/lila-modeler

$ npx lila validate examples/pedido/model.bpmn
✓ model.bpmn — 0 errors

$ npx lila run examples/pedido/model.bpmn \
    examples/pedido/as-is.scenario.json --seed 42 --replications 30
$ npx lila compare … as-is.scenario.json to-be-3-cajeros.scenario.json

05 — Screens

Model. Simulate. Replay. Decide.

Model — the bpmn-js editor with palette, properties and validation marked on the elements.

06 — FAQ

Questions, answered.

Is Lila Modeler free?

Yes. Apache-2.0, no account, no paid tier. The same engine runs in the browser, the desktop app, the CLI and the MCP server.

Where does my work live?

In the browser's local storage while you work — that is not a backup. File ▸ Save downloads the whole project as a portable .lila file.

Do I need Bizagi?

No. Lila follows the same four-level workflow and result table layout so Bizagi users feel at home, but it is fully independent.

Can two people edit the same project?

Not simultaneously. Sharing means passing a .lila file around; there is no backend and no real-time sync.

Which platforms are supported?

Any modern desktop browser for the web app (Chrome is the one tested; Safari is pending). The desktop beta ships for macOS on Apple Silicon — not notarized, so the first launch needs “Open Anyway”; see the beta guide, and do not disable Gatekeeper — and for Windows x64, whose installer is unsigned and has not been tested on a real Windows PC yet: SmartScreen will warn, and the Windows tester guide explains how to try it and report back. The Linux AppImage is built by CI but untested and not attached to the release.