rit

A TypeScript project built with the Effect library. This repository provides a foundation for building applications using modern JavaScript runtimes like Bun or Node.js, including lambda-like function handlers that can be packaged and run in containers.

Getting Started

Prerequisites

• Bun (Recommended) OR Node.js
• A package manager compatible with pnpm

Installation

Clone the repository and install dependencies:

# If using pnpm as specified in devEngines
pnpm install

# Alternative: npm install or yarn install if preferred

Project Structure

• src/: Main application source code
• examples/: Example lambda-like handlers (default export handler returning Effect.gen)
• test/: Test files (using Vitest)
• dist/: Built output directory
• tsconfig.json: TypeScript configuration
• vitest.config.ts: Testing configuration

Function Configuration (rit.function.json)

Each function directory can define a rit.function.json file. This is loaded automatically when building/running a function container.

{
  "container": {
    "baseImage": "oven/bun:1"
  },
  "runtime": {
    "memoryMb": 256,
    "cpu": 0.5,
    "timeoutMs": 15000,
    "networkMode": "none",
    "readOnlyRootFs": true,
    "maxPayloadBytes": 262144,
    "environment": {
      "RIT_ENV": "development"
    }
  }
}

BuildContainerInput.runtime values override values from rit.function.json.

Run mode is controlled with RIT_RUN_MODE:

• simulate (default): no real docker execution
• docker: builds and runs the container for real

Handler selection is controlled with RIT_HANDLER_MODULE (default: examples/functions/hello/index.ts). Event payload can be passed via RIT_EVENT_JSON (must be valid JSON).

To speed up docker mode, set RIT_BUILD_POLICY:

• if-not-present (default): only build if image is missing
• always: always rebuild before run
• never: never build; fail if image is missing

# Simulated
pnpm start

# Real docker mode (build once, then reuse image)
RIT_RUN_MODE=docker RIT_BUILD_POLICY=if-not-present pnpm start

# Fastest: never build (requires prebuilt image)
RIT_RUN_MODE=docker RIT_BUILD_POLICY=never pnpm start

Available Commands

Command	Description
pnpm dev	Start the development server with hot-reloading (requires Bun)
pnpm start	Run the application using Bun without watch mode
pnpm build	Build and bundle the project for production
pnpm test	Run all tests using Vitest in watch mode
pnpm coverage	Run tests and generate code coverage report
pnpm lint	Lint TypeScript files with ESLint
pnpm lint:fix	Auto-fix issues found by ESLint (where possible)

Tech Stack & Dependencies

Core Runtime Libraries

• Effect: A type-safe programming model for writing robust applications in Node.js, Bun, and Deno. Includes platform integration (@effect/platform, @effect/platform-bun).
• TypeScript: Strongly-typed JavaScript development with version 6+.

Development & Build Tools

• Bun: High-performance runtime and package manager (primary dev engine).
• tsdown: TypeScript bundler for building the project.
• Vitest: Fast testing framework integrated directly into your Node.js environment, built on top of Vitest's core features.
• ESLint: Static code analysis tool with specific rules configured in eslint.config.mjs.

Quality & Formatting Tools (Configured)

• .editorconfig / .prettierignore: Code style consistency enforcement.