Kamal and Blossom serve different purposes in the deployment ecosystem — but they’re often compared because both simplify app deployment for developers.
Here’s a comparison to help you understand the differences:
Kamal
- Modern CLI-based deployment tool for deploying containerized apps built by the Rails team
- Successor to Capistrano, modernized for the container era
- Uses Docker and SSH for remote deployments
- Requires manual server provisioning and ongoing maintenance
- Configuration via YAML files for deployment targets
- Only supports Dockerfile-based builds
- Manual server provisioning and maintenance required
- Requires DevOps knowledge and hands-on server management
- Supports multi-app deployments, though configuration feels complex and bolted-on
- Free and open-source
Blossom
- Fully managed PaaS with both UI and git-based workflows
- One-click integration with GitHub, GitLab, and Bitbucket
- Flexible build support: Buildpacks, Nixpacks, Dockerfile, or pre-built images
- 5-day free trial with predictable per-server pricing
- Bring your own infrastructure — works with any cloud provider
- Full server control with SSH access
- Automated server provisioning and maintenance
- Minimal DevOps knowledge required to get started
- Supports all major cloud providers: AWS, Azure, GCP, DigitalOcean, Hetzner, Linode, Vultr, OVHCloud — even on-prem
Quick Comparison
| Feature | Kamal | Blossom |
|---|---|---|
| Deployment | CLI and YAML-based | UI and git-based |
| Pricing | Free, open-source | Simple per server pricing |
| Build Process | Dockerfile only | Multiple build options |
| Infrastructure | Self-Managed | Managed |
| Server Access | Full access | Full SSH access |
| Learning Curve | Steep | Gentle |
| Setup Time | Hours to days | Minutes |
Conclusion
Kamal is a command-line deployment tool and spiritual successor to Capistrano. It’s built by the Rails team and designed for developers are okay with spending some extra time managing their own servers. Without some DevOps experience the tool can feel a little unpolished. It’s free, making it attractive for teams who are okay with spending extra time to manage the infrastructure.
Blossom, on the other hand, is a fully managed Platform-as-a-Service (PaaS) that handles everything from provisioning to deployment. It saves significant time and resources by reducing the need for DevOps expertise. It’s ideal for teams who want to focus on building their application rather than managing deployment infrastructure.
See How Blossom Compares on Cost
Use the calculator to compare Blossom's predictable pricing against other platforms.
Want a deeper dive? Read our comprehensive comparison of popular deployment platforms.