@push-based/jiti-tsc

jiti does not support TypeScript config files. jiti-tsc bridges this gap by converting tsconfig.json paths into jiti-compatible options for DX.

Features

This library does one simple thing: it converts TypeScript path aliases to jiti-compatible alias options and wrapd the original jiti API to make it easier to use in monorepo environments.

✅ Full TypeScript configuration support:

• ✅ FAutomatically detected from the tsconfig.json file in the current working directory
• ✅ FAccepts custom tsconfig path via the JITI_TSCONFIG_PATH
• ✅ FCLI tool supporting tsconfig options
• ✅ FProgrammatic API supporting tsconfig options

Installation

npm install @push-based/jiti-tsc

Quick Start

Usage:

# Capability mode (automatic)
NODE_OPTIONS="--import jiti-tsc" node file.ts

# Runner mode (CLI)
npx jiti-tsc file.ts

With custom tsconfig path:

JITI_TSCONFIG_PATH=./tsconfig.json NODE_OPTIONS="--import jiti-tsc/register" node your-file.ts

Note: The JITI_TSCONFIG_PATH environment variable can be used to specify a custom tsconfig path. Defaults to ./tsconfig.json if not specified.

CLI Usage

# Display help information
npx jiti-tsc help

# Run jiti without tsconfig (uses default resolution)
npx jiti-tsc ./path/to/module.ts

# Run jiti with tsconfig-derived options (via environment variable)
JITI_TSCONFIG_PATH=./tsconfig.json npx jiti-tsc ./path/to/module.ts

# Print resolved jiti configuration from tsconfig.json
JITI_TSCONFIG_PATH=./tsconfig.json npx jiti-tsc print-config

# Print configuration to a file
JITI_TSCONFIG_PATH=./tsconfig.json npx jiti-tsc print-config --output=./resolved-config.json

CLI Commands

By default, jiti-tsc runs jiti with tsconfig-derived options. If the first argument is not help or print-config, it is treated as arguments to jiti.

Default (jiti)

Runs the jiti command line tool with options derived from a TypeScript configuration file.

Note: Use the JITI_TSCONFIG_PATH environment variable to specify the tsconfig path.

# Run jiti with tsconfig options (tsconfig path via environment variable)
JITI_TSCONFIG_PATH=./tsconfig.json npx jiti-tsc ./path/to/module.ts

# Run jiti without tsconfig (uses default resolution)
npx jiti-tsc ./path/to/module.ts

print-config

Loads a TypeScript configuration file and prints the resolved jiti options.

# Print to stdout
JITI_TSCONFIG_PATH=./tsconfig.json npx jiti-tsc print-config

# Print to file
JITI_TSCONFIG_PATH=./tsconfig.json npx jiti-tsc print-config --output=./resolved-config.json

help

Displays help information.

npx jiti-tsc help
npx jiti-tsc --help
npx jiti-tsc -h

CLI Options

| Option | Type | Description | | ----------------- | --------- | ------------------------------------------------------------------------- | | --output <path> | string | Output path for print-config command (prints to stdout if not provided) | | -h, --help | boolean | Display help information |

Environment Variables:

• JITI_TSCONFIG_PATH — Path to TypeScript configuration file. Use this environment variable to specify which TypeScript configuration to load.

Positional Arguments:

npx jiti-tsc [command] [options]

• command — Optional command: print-config or help. If omitted or not recognized, arguments are passed to jiti (default behavior).

TypeScript Configuration

The tool works with your existing tsconfig.json files.

• Use the JITI_TSCONFIG_PATH environment variable to specify which TypeScript configuration to load.

// tsconfig.json
{
  "compilerOptions": {
    "paths": {
      "@acme/*": ["packages/*/src"]
    }
  }
}

The tool will parse the paths configuration and convert them to jiti-compatible aliases for monorepo package resolution.

API Reference

importModule<T>(options)

Imports a TypeScript module using jiti with optional tsconfig support for path alias resolution.

import { importModule } from '@push-based/jiti-tsc';

const module = await importModule({
  filepath: './config.ts',
  tsconfig: './tsconfig.json',
});

TS Config Mapping

Jiti supports several options that can be directly derived from the TypeScript configuration.

| Jiti Option | Jiti Type | TypeScript Option | TypeScript Type | Description | | ---------------- | ------------------------ | ----------------- | -------------------------- | ------------------------------------------------------------------------------------------ | | alias | Record<string, string> | paths | Record<string, string[]> | TypeScript paths are converted to jiti alias objects with absolute paths resolved. [*] | | interopDefault | boolean | esModuleInterop | boolean | Maps esModuleInterop to enable default import interop in jiti. | | sourceMaps | boolean | sourceMap | boolean | Maps sourceMap to enable sourcemap generation in jiti. | | jsx | boolean | jsx | JsxEmit (enum: 0-5) | Any non-None jsx setting is mapped to enable JSX support in jiti. [**] |

[*] Jiti does not support overloads (multiple mappings for the same path pattern). If overloads are detected, it throws an error. [**] Jiti maps to a boolean and does not support the jsx option values as TypeScript does (only enables/disables JSX processing).