Scaffolding a New Cloud Provider Package

This guide walks through creating a new reventless-<provider> package from scratch.

Prerequisites

• Familiarity with the Framework Developer Guide
• Understanding of the Adapter Pattern
• A Pulumi provider for your target cloud platform

1. Create the Package

Provider packages live under reventless/ (the framework root), not packages/ (which is build tooling and docs only):

mkdir reventless/reventless-myprovider
cd reventless/reventless-myprovider

2. Set Up rescript.json

The reventless-ppx flag must come before sury-ppx, and the output suffix is .res.mjs:

{
  "name": "reventless-myprovider",
  "version": "1.0.0-alpha.0",
  "sources": [
    {
      "dir": "src",
      "subdirs": true
    }
  ],
  "ppx-flags": ["@reventlessdev/reventless-ppx/bin", "sury-ppx/bin"],
  "bsc-flags": ["-open RescriptCore"],
  "dependencies": [
    "@reventlessdev/reventless-spec",
    "@reventlessdev/reventless-core",
    "@reventlessdev/reventless-infra",
    "rescript-myprovider-sdk"
  ],
  "suffix": ".res.mjs"
}

3. Set Up package.json

{
  "name": "@reventlessdev/reventless-myprovider",
  "version": "1.0.0-alpha.0",
  "private": true,
  "scripts": {
    "build": "rescript build",
    "start": "rescript watch",
    "rebuild": "pnpm run clean && pnpm run build",
    "clean": "rescript clean",
    "test": "jest"
  },
  "dependencies": {
    "@reventlessdev/reventless-core": "workspace:*",
    "@reventlessdev/reventless-spec": "workspace:*",
    "@reventlessdev/reventless-infra": "workspace:*"
  }
}

4. Implement Adapter Interfaces

For each component you want to support, implement the adapter interfaces defined in reventless-core. See the Adapter Pattern for the full checklist.

Start with the core event sourcing adapters:

1. EventLog storage — append-only event log with optimistic concurrency
2. CommandTopic channel — message queue for commands
3. EventTopic publisher — pub/sub for events

5. Export Pre-Configured Builders

Expose builder modules that pre-wire the framework functors with your adapters:

// MyProviderEventLog.res
module Make = (Spec: Reventless.EventLog.Spec) =>
  EventLog_Builder.Make(Spec, MyEventLogStorage, MyEventTopicPublisher)

This is the API surface that application developers use.

6. Reference the AWS Implementation

The reventless-aws package is the canonical reference implementation. When in doubt, examine how it implements a given adapter — the patterns apply directly to other providers.

reventless/reventless-aws/src/adapter/
├── EventLog/
├── CommandTopic/
├── EventTopic/
├── QueryDb/
├── Task/
└── DcbEventLog/