Side by side
OCIregistry vs Singularity Container Services
Both stand on container registries. Which one you can start free with, which one lets you read the code, and what each costs once you pay.
Free plan APILinuxSelf-hosted
OCIregistry focuses on pull-through image caching for Kubernetes-oriented deployments. Its broad upstream, transport, preload, and cache-management options are balanced by a single-instance serving limit and documented path constraint.
Visit OCIregistry Free plan APILinuxWeb
SCS may suit users who need hosted container building, sharing, and verification at no charge within its plan limits. Look elsewhere for a service beyond October 22, 2026, since SCS is scheduled to shut down and stored data will be deleted.
Visit Singularity Container ServicesThe facts
| OCIregistry | Singularity Container Services | |
|---|---|---|
| Free plan | Yes | Yes |
| Open source | Not published | Not published |
| Runs on | API, Linux, Self-hosted | API, Linux, Web |
| Lowest paid plan | Not published | Free or on request |
| Plans published | None | 1 |
| Maker | Not published | Not published |
| Website | github.com | cloud.sylabs.io |
| On container registries | #28 of 60 | #24 of 60 |
OCIregistry: what it does well
- Pulls from multiple upstream registries
- Supports mutual TLS and basic authentication
- Cache can be copied as files
- Administrative API includes pruning and listings
- Preloads images from URLs or tarballs
What to know first
- Only one server instance can serve clients
- Maximum image path length is four segments
- No documented security certifications or compliance attestations
- Modified MIT License restricts AI training use
Singularity Container Services: what it does well
- Free hosted container service with SIF and OCI support.
- Remote Builder works on systems without root privileges.
- Role-based access controls manage Container Library sharing.
- Keystore signs and verifies containers with cryptographic keys.
- Supports sign-in through Google, GitHub, GitLab, or Microsoft.
What to know first
- Free plan allows one project and 500 build minutes per rolling 30 days.
- Library storage is capped at 11GB on the free plan.
- Free plan is x86 only.
- Service is scheduled to cease operating on October 22, 2026.
Alternatives to OCIregistry Alternatives to Singularity Container Services The whole list