How Git-Push Deployments Work Under the Hood

git push deploys to production. It's the workflow that Heroku popularized, Vercel polished, and dozens of tools since have copied. But most developers who use it every day don't know what's happening between the push and the live URL. Understanding the pipeline helps you debug it when it breaks and make smarter decisions about your deployment setup. Here's what happens at each step. Step 1: The Webhook Fires When you push to a repository on GitHub, GitLab, or Gitea, the platform sends an HTTP POST to any webhooks registered for that repo. The payload includes the commit SHA, the branch name, the repository URL, and the pusher's identity. Your deployment platform registers one of these webhooks when you connect a repository. On Vercel, it happens automatically when you import a project. On Coolify, Dokploy, or a self-hosted tool, you configure it from the dashboard during project setup. The webhook request is just an HTTP POST. Your deployment server needs a public IP and an open port t