CertMate is an open-source SSL certificate management system designed for modern infrastructure teams managing certificates across multiple cloud providers and datacenters. It solves the operational complexity of manual certificate renewal, DNS validation, and secure storage by providing a unified API and web interface. Built in Python with Docker containerization, it supports Let’s Encrypt, DigiCert ACME, and private CAs with full automation for certificate issuance, renewal, and revocation. CertMate is ideal for DevOps teams, cloud engineers, and security administrators who need to manage hundreds of domains with varying DNS providers while ensuring zero-downtime certificate updates and compliance with enterprise security standards.
The system is engineered for scalability and reliability, featuring multi-account support for DNS providers like Cloudflare, AWS Route53, Azure DNS, and Google Cloud DNS, enabling environment separation (production/staging), team isolation, and disaster recovery scenarios. With pluggable storage backends including Azure Key Vault, AWS Secrets Manager, HashiCorp Vault, and Infisical, CertMate ensures secure certificate storage without compromising on auditability or accessibility. Its REST API and web dashboard allow both automated scripts and human operators to manage certificates efficiently, making it a robust alternative to manual certbot workflows or fragmented certificate management tools.
What You Get
- Multi-DNS Provider Support - CertMate integrates with 22 DNS providers including Cloudflare, AWS Route53, Azure DNS, Google Cloud DNS, DigitalOcean, and PowerDNS via certbot plugins, enabling automated DNS-01 challenges for certificate validation across hybrid and multi-cloud environments.
- Automatic Certificate Renewal - Certificates are automatically renewed 30 days before expiry, with built-in rate limit awareness for Let’s Encrypt and support for wildcard and multi-domain (SAN) certificates.
- Enterprise Storage Backends - Certificates can be securely stored in Azure Key Vault, AWS Secrets Manager, HashiCorp Vault, or Infisical, with migration support and backward compatibility for existing local filesystem deployments.
- REST API with Swagger UI - Full programmatic control via a documented REST API accessible at
http://localhost:8000/docs/, supporting certificate issuance, renewal, backup, and retrieval in PEM or ZIP formats.
- Web Dashboard - A modern, responsive UI built with Tailwind CSS for managing certificates, DNS providers, storage backends, and backups without command-line interaction.
- Unified Backup & Recovery - Atomic snapshots of certificates, DNS configurations, and application settings with configurable retention policies, on-demand backup creation via API or UI, and seamless restore functionality.
- Multi-Account Management - Configure multiple DNS provider accounts per service (e.g., separate Cloudflare accounts for staging and production) to enable environment isolation, region-specific management, and permission scoping.
- Bearer Token Authentication - Secure API access enforced via environment variable (API_BEARER_TOKEN), ensuring only authorized clients can issue or manage certificates.
- Docker & Kubernetes Ready - Official Docker images and docker-compose.yml provide immediate deployment; architecture is stateless and designed for Kubernetes horizontal scaling.
- SDK Examples & Webhooks - Includes Python, Bash, Ansible, and Terraform examples for automation; supports webhooks to trigger external systems on certificate renewal events.
Common Use Cases
- Building a multi-tenant SaaS dashboard with real-time analytics - Manage TLS certificates for hundreds of customer subdomains using Cloudflare and AWS Route53, with automatic renewal and centralized backup to HashiCorp Vault for compliance.
- Creating a mobile-first e-commerce platform with 10k+ SKUs - Automate certificate issuance for dynamic domains using Google Cloud DNS and store certificates in AWS Secrets Manager to ensure secure, scalable HTTPS termination across global edge locations.
- Problem: Manual certificate renewal causing outages → Solution: CertMate - A team manually tracked certificate expirations across 50 domains using certbot, leading to two outages. After deploying CertMate with Cloudflare DNS and local storage, all renewals became automated with alerts and audit logs.
- DevOps teams managing microservices across multiple cloud providers - Use CertMate to unify certificate management for services running on AWS, Azure, and GCP by configuring multi-account DNS providers and storing secrets in Infisical for team collaboration.
Under The Hood
CertMate is a modular SSL certificate management system designed to streamline the provisioning, renewal, and monitoring of certificates across diverse infrastructure environments. It emphasizes extensibility through support for multiple DNS providers and storage backends, making it adaptable to various deployment scenarios.
Architecture
The system adopts a modular monolithic structure that cleanly separates concerns such as API handling, business logic, and external integrations. This design enables clear boundaries between components and supports scalable growth.
- Strategy and factory patterns are employed to manage DNS provider configurations and certificate authority interactions
- The layered architecture ensures separation between authentication, storage, and core operational logic
- A well-defined module organization enhances maintainability and extensibility
Tech Stack
Built with Python 3.11, CertMate leverages a range of tools and libraries to support robust functionality and cross-platform compatibility.
- Flask is used for web routing and API endpoint creation, enabling a flexible and extensible interface
- Third-party integrations include cloud storage providers like AWS, GCP, and Azure for certificate persistence
- Docker multi-stage builds and Makefiles facilitate streamlined deployment and development workflows
- Testing is supported through pytest, with CI/CD pipelines in place for automated validation
Code Quality
The codebase reflects a mixed quality profile with solid test coverage but some inconsistencies in structure and error handling.
- A comprehensive suite of unit and end-to-end tests ensures functional reliability across modules
- Try/except blocks are widely used to improve resilience, though error propagation could be more consistent
- Inconsistent naming and structural patterns are observed in core logic organization
- Legacy code artifacts and duplicated modules indicate areas where refactoring would improve maintainability
What Makes It Unique
CertMate distinguishes itself through its API-first approach and broad ecosystem support, offering a unified solution for certificate lifecycle management.
- Deep integration capabilities with multiple DNS and storage providers enable seamless deployment across varied infrastructures
- Modular architecture allows for easy customization and extension without disrupting core functionality
- A focus on observability through structured logging and metrics enhances operational visibility