CycloneACME
ACME Client Library

CycloneACME is an ACME (Automatic Certificate Management Environment) client implementation designed for embedded applications. It can be used to automate the management of X.509 certificates, including ordering, renewing, and revoking them, with a remote certification authority like Let's Encrypt. ACME enables the deployment of public-key infrastructure on Internet-facing devices, such as HTTPS servers, at a very low cost.

CycloneACME is available either as open source (GPLv2 license) or under a royalty-free commercial license (non-GPL license). We also propose an evaluation license (90-day license in source form) with technical support for an easier onboarding and effective evaluation of our software.

Main Features

• ACME v2 protocol implementation
• Client mode of operation
• ACME account management (creation, update, deactivation and key rollover)
• Certificate management (ordering, renewal and revocation)
• Supports RSA, ECDSA and EdDSA certificates
• Supports standard ACME challenges (HTTP, DNS and TLS-ALPN)
• ACME-DNS client provides a simple way to automate ACME DNS challenges
• Compatible with ACME servers such as Let's Encrypt, Encryption Everywhere or Buypass Go SSL
• Comprehensive user API
• Flexible memory footprint. Built-time configuration to embed only the necessary features
• Portable architecture (no processor dependencies)
• The library is distributed as a full ANSI C and highly maintainable source code

Supported ACME Challenges

• http-01 (HTTP-based challenge type)
• tls-alpn-01 (TLS-based challenge type)
• dns-01 (DNS-based challenge type)

Supported Signature Algorithms

• RSA
• ECDSA
• Ed25519
• Ed448