Boulder vs DigiCert Private CA
Boulder
github.com
DigiCert Private CA
digicert.comSide by side
| Figure | Boulder | DigiCert Private CA |
|---|---|---|
| Price from | Free | — |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| Web | — | Yes |
| Linux | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 1 | 1 |
| Spec score · Public Key Infrastructure Software | 8.0 (#9) | 7.4 (#15) |
| Purpose | Boulder is an ACME-based certificate authority written in Go and is the software that runs Let's Encrypt. | DigiCert Private CA builds and operates privately trusted PKI for an organization’s users, devices, applications, and digital assets across on-premises and cloud environments. |
| Support | The maintainers prioritize support and development work that advances Let's Encrypt's mission and warn that timely support may not be available for other deployments. | DigiCert provides PKI specialists for installation, migration, and other support, with support documents and Monday-Friday 24/7 specialist availability. |
Plans
In their own words
Boulder
Boulder is an open-source ACME certificate authority written in Go and used to run Let’s Encrypt. ACME lets a certificate authority verify control of an identifier and allows subscribers to issue or revoke certificates for identifiers they control. Boulder divides its work among web front ends, registration and validation authorities, a certificate authority, storage authority, publisher, and CRL updater. These boundaries separate CA functions by security context, with the certificate authority receiving instructions from the registration authority. Components communicate through gRPC, and the software stores ACME accounts, authorizations, challenges, orders, and certificates. Boulder is free under the Mozilla Public License 2.0 and is listed for API, Linux, and self-hosted use. Maintainers recommend Docker and Docker Compose for development and experimentation, and document connecting Certbot or another ACME client to a local instance. That Docker environment is not suitable for production: it uses publicly available private key material, exposes debug ports, and is described as brittle when components fail. Boulder is built for Let’s Encrypt and Web PKI baseline requirements; maintainers say it often does not fit other organizations’ production needs.
DigiCert Private CA
DigiCert Private CA has no write-up on Specifiction yet; its figures are above.