docs: add TECH_STACK.md (#4883)

CONTRIBUTING.md

@@ -4,6 +4,8 @@ # Contributing to Coolify
 
 You can ask for guidance anytime on our [Discord server](https://coollabs.io/discord) in the `#contribute` channel.
 
+To understand the tech stack, please refer to the [Tech Stack](TECH_STACK.md) document.
+
 ## Table of Contents
 
 1. [Setup Development Environment](#1-setup-development-environment)

TECH_STACK.md

@@ -0,0 +1,32 @@
+# Coolify Technology Stack
+
+## Frontend
+
+-   Vue.js
+-   Tailwind CSS
+-   Monaco Editor (Code editor component)
+-   XTerm.js (Terminal component)
+-   Livewire (Reactive components)
+
+## Backend
+
+-   Laravel (PHP Framework)
+-   PostgreSQL (Database)
+-   Redis (Caching & Real-time features)
+-   WebSocket (Real-time communication)
+
+## DevOps & Infrastructure
+
+-   Docker
+-   Docker Compose
+-   Node.js (for some tooling)
+-   Vite (Build tool)
+
+## Languages
+
+-   PHP
+-   JavaScript/TypeScript
+-   HTML/CSS
+-   Shell/Bash scripts
+-   YAML
+-   JSON