Deploying Apps
There are three ways to deploy to Caster: paste code, upload a file, or git push. This page explains how deployments work, how to view build logs, and how to roll back.
How Deployments Work
Every deployment follows the same pipeline:
- Receive — Caster receives your files (paste, upload, or git push)
- Build — A Docker image is built (nginx for static sites, or your custom Dockerfile)
- Deploy — The new container replaces the previous one
- Route — HTTPS traffic is routed to your container automatically
The entire process typically takes under a minute.
Deployment Methods
Paste Deploy
Paste HTML or other files directly in the browser or via the API. Best for quick deploys and chatbot-generated sites.
File Upload
Upload a .zip, .tar.gz, or .tar archive. Good for projects with multiple files.
Git Push
Push to main to trigger a deployment. Requires an SSH key. Best for ongoing development.
Static Sites
If your project doesn't include a Dockerfile, Caster automatically serves it as a static site using nginx. Your files are copied into /usr/share/nginx/html and served on port 80.
If you include a Dockerfile, Caster uses it instead — this lets you deploy dynamic apps in any language.
Viewing Deployment History
From the site detail page, you can see all deployments with their status, commit/content hash, and timestamp. Click Logs on any deployment to view the build output.
Build Logs
Build logs show the full output from the Docker build. If a deployment fails, the build log will contain the error. Common issues:
- Build errors in your Dockerfile
- The container not listening on the port declared by
EXPOSE(defaults to 80) - Missing dependencies
Rolling Back
If a deployment causes issues, you can roll back to the previous version:
- Go to the site detail page
- Click Rollback in the deployment history section
- The previous container image is redeployed immediately — no rebuild needed
Rollbacks are instant because they reuse the previously built container image.