acme.sh vs SSL.com Certificate Lifecycle Management

acme.sh is a free Unix shell ACME client for automating SSL/TLS certificate issuance, renewal, and installation. Its installer creates a daily cron job to check certificates and renew them when needed. Written purely in shell, it is compatible with Bash, dash, and sh; the README says general use needs neither Python nor root or sudo access. It supports ECDSA, RSA, SAN, and wildcard certificates, with validation modes including webroot, standalone, standalone TLS-ALPN, Apache, Nginx, DNS, DNS alias, stateless, and DNS persist. ZeroSSL is the default certificate authority. Listed alternatives include Let's Encrypt, SSL.com, Google Public CA, Actalis, Pebble strict mode, and any RFC8555-compliant CA. The project says API integrations cover most DNS providers. Renewal uses a CA’s ACME Renewal Information when available, with a 30-day fallback rule otherwise. Manual DNS mode cannot renew automatically because each renewal requires a new TXT record to be added by hand. Tested systems listed include macOS, Windows through Cygwin, FreeBSD, and multiple Linux distributions. The project is GPLv3 licensed and officially maintained by ZeroSSL; release tags from version 3.1.6 onward are signed with the maintainer’s SSH key, while earlier tags are unsigned.

SSL.com Certificate Lifecycle Management supplies SSL.com certificates for use inside an existing certificate-lifecycle platform or a custom workflow. It acts as the Certificate Authority rather than a complete CLM system. An SSL.com account lists certificates issued through that account, supports downloading, renewal, reissue, and individual or bulk revocation, and sends email alerts before expiry. ACME can automate issuance and renewal. Venafi TPP users can connect through the Adaptable Driver for SSL/TLS, client-authentication, S/MIME, and code-signing certificates. The AnyCA Gateway REST plugin connects with Keyfactor Command 12.3 and later for issuing, revoking, and synchronizing certificates. Two REST/JSON APIs are available, with the Developer Portal API recommended for new integrations. Native network-wide discovery, multi-CA inventory, approval workflows, custom request forms, and fleet-wide RBAC are not provided. The service runs in the cloud and supports certificate profiles, SCEP, EST, HSM integration, cloud signing, trusted timestamping, and CI/CD signing.