Languages

Per-language support and serve adapters for the Go, TypeScript, and Python Workflow SDKs.

The three SDKs are contract-locked — the same round-trip tests assert their opcode envelopes, protocol types, and HMAC signatures are byte-identical. That means the protocol surface is uniform. What differs is how complete each implementation is and which HTTP frameworks each one can serve behind.

At a glance

	Go	TypeScript	Python
Package	`github.com/ductor-io/ductor-go`	`@ductor/sdk`	`ductor` (PyPI)
Version	—	`0.1.0`	—
`execute` (run steps)	✅	✅	❌ HTTP 501
`discover` / `health-check` / `code`	✅	✅	✅
Protocol types + HMAC	✅	✅	✅ (round-trips)

Python execution is not supported

Go and TypeScript can execute workflows end to end. Python supports registration, discovery, health checks, protocol types, and signing, but its execute action returns HTTP 501.

Per-language support

Module github.com/ductor-io/ductor-go (Go 1.25). Install and import the ductor package; serve adapters live in the ductor/serve subpackage.

go get github.com/ductor-io/ductor-go

main.go

import (
    "net/http"

    "github.com/ductor-io/ductor-go/ductor"
    "github.com/ductor-io/ductor-go/ductor/serve"
)

client := ductor.NewClient(ductor.ClientOptions{
    AppID:      "checkout",
    SigningKey: []byte(os.Getenv("DUCTOR_SIGNING_KEY")),
})
// register workflows on client...

http.Handle("/api/ductor", serve.NetHTTP(client))

Serve adapters (sdks/go/ductor/serve/):

Adapter	Status	Notes
`serve.NetHTTP`	Production	Stdlib `http.Handler`. Mount on any path.
`serve.Lambda`	Production	AWS API Gateway proxy integration; handles base64 bodies and case-insensitive headers.
`serve.Connect`	Pass-through	Forwards to `NetHTTP` under a Connect-conventional path prefix. Not a Connect-RPC bridge.

Package @ductor/sdk, version 0.1.0. It has full protocol parity with Go — Client, the step API (run, sleep, sleepUntil, waitForEvent, waitForSignal, invoke), opcode types, and the HMAC sign/verify helpers.

npm install @ductor/sdk

Serve adapters are published as package subpath exports (from package.json):

Import	Framework
`@ductor/sdk/serve/express`	Express
`@ductor/sdk/serve/hono`	Hono
`@ductor/sdk/serve/next`	Next.js
`@ductor/sdk/serve/nethttp`	Node `http`

Package ductor on PyPI. Install the core, or the fastapi extra for the Starlette/FastAPI adapters.

pip install ductor          # core
pip install ductor[fastapi] # + FastAPI/Starlette adapters

You serve it through the ASGI adapter, which works with any ASGI 3.0 server — FastAPI, Starlette, Uvicorn, or Hypercorn (ductor.serve.asgi.asgi_app):

app.py

from fastapi import FastAPI
from ductor import Client, WorkflowOpts, Trigger
from ductor.serve.asgi import asgi_app

app = FastAPI()
client = Client(app_id="checkout")
client.workflow("place-order", WorkflowOpts(trigger=Trigger(event="order.placed")))

app.mount("/api/ductor", asgi_app(client))

Workflow execution is unavailable in Python

The Python SDK supports discover, health-check, and code. The execute action returns HTTP 501, so use this SDK for registration and discovery, not workflow execution.

Operational gotchas

These apply regardless of language:

ductor dev still needs Postgres. The dev harness embeds Redis (via miniredis) but not the database — you must provide a reachable Postgres.
.env is not auto-loaded in production. Local dev may read it, but a production process expects real environment variables to be set.
An empty signing key disables HMAC verification. Convenient in development, unacceptable in production — always configure a key for a deployed bridge.

Bridge protocol

The actions, opcodes, and HMAC scheme every adapter above implements.

CLI reference

The ductor subcommands, including ductor dev.