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README.md

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+# Package Diff Command
+
+Generates a report of changes to npm packages in different formats. Inspired by [IonBazan/composer-diff](https://github.com/IonBazan/composer-diff).
+
+## Installation
+
+To install globally, run
+
+```sh
+npm install -g @sephsekla/package-diff
+```
+
+Alternatively, you can install on the first run by specifying the package:
+
+```sh
+npx package-diff -p @sephsekla/package-diff
+```
+
+### Requirements and Compatibility
+
+Tested on current, pending and LTS Node versions:
+
+- Node 16
+- Node 18
+- Node 19
+- Node 20
+
+Currently `npm` only, however `pnpm` and `Yarn` support is planned.
+
+## Usage
+
+Compare installed npm packages to the latest git commit:
+
+```sh
+npx package-diff
+```
+
+### Options
+
+#### Base
+
+```sh
+-b, --base 
+```
+
+The base to compare against (a git branch or commit). Default `HEAD`
+
+#### Format
+
+```sh
+-f, --format
+```
+
+The format to output:
+
+| Option | Description |
+| - | - |
+| `mdlist` | A markdown-formatted list of changes *(Default)*
+| `mdtable` | A markdown-formatted table of changes
+| `json` | A json object featuring packages, operations and versions. Recommended for CI and chain commands.