cleat

README

cleat

Durable workflow engine -- runs on PostgreSQL, MySQL, or SQL Server. Write in Go, compile to WASM, deploy via INSERT.

go install github.com/cleat-team/cleat/cmd/cleat@latest
cleat dev --entry-point PlaceOrder \
    --input '{"userID":"u1","cart":[{"sku":"widget","quantity":2}]}' \
    ./testdata/basic/

What is Cleat

Cleat is a durable workflow engine that turns your existing PostgreSQL, MySQL, or SQL Server database into an orchestration backend. Workflows are written in Go (or Rust), compiled to WebAssembly, and stored directly in the database. A stateless Go worker daemon polls the database, claims ready workflows, and drives execution with deterministic replay, checkpointing, and failover -- no new infrastructure required.

Cleat ships with an embedded Svelte web UI for monitoring, a CLI for build/deploy/ management, and a WASM-free test framework for fast unit tests. It is self-hosted, Apache 2.0 licensed, and designed for teams that already run a supported relational database.

Quick Start

# 0. Verify your toolchain (one command)
make setup

# 1. Install the CLI
go install github.com/cleat-team/cleat/cmd/cleat@latest

# 2. Start Postgres and apply the schema. `cleat-worker` (step 5) also
#    applies migrations/postgres/*.sql automatically on boot, but `cleat
#    deploy` (step 4) does not, and deploy runs first in this walkthrough --
#    so the schema has to exist before that. See
#    docs/explanation/postgresql-schema.md for the full procedure.
docker compose -f docker-compose.partner.yml up -d postgres
for f in migrations/postgres/*.sql; do
    psql "postgres://postgres:postgres@localhost:5432/cleat?sslmode=disable" -f "$f"
done

# 3. Compile a workflow package to WASM
cleat build -o ./out ./testdata/basic/
# Wrote ./out/cancel_order.wasm -- cleat build bundles every entry point
# in the package (PlaceOrder, CancelOrder, LongRunning) into one module,
# named after the first entry point it found. All three are still callable
# from that one file; --entry-point at trigger time (step 6) picks one.

# 4. Deploy to your database
cleat deploy --db "postgres://postgres:postgres@localhost:5432/cleat?sslmode=disable" \
    --name place_order ./out/cancel_order.wasm

# 5. Start the worker daemon
cleat-worker --db "postgres://postgres:postgres@localhost:5432/cleat?sslmode=disable"

# 6. Trigger a workflow (via REST API) -- POST .../<name>/start, not POST
#    .../workflows (that route is GET-only and returns 405 on POST)
curl -X POST http://localhost:8080/api/workflows/place_order/start \
    -d '{"input":{"userID":"u1","cart":[{"sku":"widget","quantity":2}]},"entry_point":"PlaceOrder"}'

See the Quick Start Tutorial for a complete walkthrough with a real-world example.

Key Features

• Durable execution -- deterministic replay via event history; workflows survive worker crashes, restarts, and network partitions.
• Multi-DB backends -- PostgreSQL 16+, MySQL 8.0+, SQL Server 2022+, each with an independent implementation of the full workflow store. Database-enforced tenant isolation (row-level security) exists on PostgreSQL and SQL Server -- FORCEd RLS policies on PostgreSQL, a native SECURITY POLICY/FILTER PREDICATE on SQL Server. MySQL has no row-level security feature at all, so it is documented single-tenant only rather than emulating isolation the database can't back up (see docs/reference/multi-tenancy.md). All of the above is engine support, not CLI support: the cleat CLI (deploy, versions, rollback, schedule, lock, plugin) only connects to PostgreSQL today, and refuses a MySQL or SQL Server connection string with an explicit error rather than a confusing driver failure. cmd/deploy-workflow --driver mysql|mssql is the one multi-dialect entry point, and it covers deploy only (see tiers.yaml).
• Plugin system -- extensible via LLM, Slack, webhooks, and custom plugins; plugins run in-process with lifecycle hooks.
• WASM workflows -- write in Go, Rust, Python, Java, or AssemblyScript, compile to WebAssembly. wasmtime is the backend of record (CPU/wall-clock/memory limits via epoch interruption, fuel, and store limits); wazero is a pure-Go, CGO-less fallback with no compute-bound fencing -- see docs/explanation/security-model.md.
• Signals and human-in-the-loop -- AwaitSignals pauses workflows for external input; signals are recorded in the event history for deterministic replay.
• Saga / compensating transactions -- structured rollback with DurableDefer, DurableDeferFunc, and cleat.NewSaga().
• Horizontal scaling -- stateless workers, SELECT ... FOR UPDATE SKIP LOCKED claim model, scale out by adding worker processes.
• CLI toolchain -- cleat build, vet, deploy, versions, rollback, and cron schedule management.
• Observability -- embedded Svelte web UI, Prometheus metrics, structured logging.

Documentation

Section	Description
Tutorials	Step-by-step walkthroughs: quick start, first workflow, signals
How-To Guides	Practical guides: plugins, testing, deployment
Reference	CLI reference, SDK API, worker configuration
Explanation	Architecture, execution model, security, WASM compilation
Operations	Production deployment, disaster recovery, upgrading
Migration Guides	Migrating from Temporal, DBOS, Restate
Contributor Guide	Setting up a dev environment, coding standards, PR process

Start at the Documentation Home to find the right page for your goal.

Installation

# Install all CLI tools
go install github.com/cleat-team/cleat/cmd/cleat@latest
go install github.com/cleat-team/cleat/cmd/cleat-worker@latest
go install github.com/cleat-team/cleat/cmd/cleat-gen@latest

Or build from source: git clone https://github.com/cleat-team/cleat.git && cd cleat && go install ./cmd/...

License

Apache 2.0. See LICENSE for details.