Caddy

Overview

Caddy is a self-hosted server platform that can serve websites or act as a proxy. Its automatic HTTPS behavior is central to its operation: it obtains and renews TLS certificates for sites, and redirects HTTP traffic to HTTPS by default. The combination makes certificate management and secure redirects part of the server’s default workflow.

Caddy can run in several forms, from a command-line process or system service to a container, Kubernetes workload, or embedded component. The maker says its TLS defaults meet PCI DSS, NIST, and HIPAA compliance requirements. That describes the defaults; operators still need to assess whether their deployment meets the requirements that apply to them.

For more options in this category, see Reverse Proxy Software.

Key features

Proxying and traffic handling

Caddy’s reverse proxy supports HTTP, HTTPS, WebSockets, gRPC, and FastCGI. It also provides load balancing and health checks, covering common needs when routing requests among backend services. TLS termination is supported, while response caching is not listed as a capability.

Configuration and extensibility

Operators can configure Caddy with JSON through a RESTful API, use the Caddyfile, or select another configuration adapter. This offers both API-driven and file-based approaches. Compile-time plugins can add capabilities, and are built into Caddy’s static binary.

For DNS challenges, Caddy integrates with Cloudflare, DigitalOcean, Route 53, and dozens of other providers through libdns. The software’s dependencies are verified with Go modules, and release artifacts are cryptographically signed.

Pricing

Caddy’s software is free, with no paywalled features according to its maker. Community help is available through the forum. Paid sponsorship tiers add support and other services; the software license remains unchanged.

Platforms

Caddy is listed for Linux, macOS, and Windows, as well as Android, web, and API environments. It is self-hosted, and can be deployed as a command-line process, system service, container, Kubernetes workload, or embedded component. The configuration method supports both API-based and other configuration approaches.

Who it's for

Caddy is suited to operators looking for a self-hosted web server or reverse proxy with automatic certificate acquisition and renewal. Its support for several proxy protocols, load balancing, health checks, and multiple deployment forms gives infrastructure teams flexibility in how they route and run services. The API, Caddyfile, and configuration adapters also suit teams with different configuration practices.

Organizations that need private support or service commitments can consider the paid sponsorship tiers, while those seeking the software itself can use the free offering. The paid plans vary considerably in support access, response guarantees, development priority, and professional services discounts.

Pros and cons

• Pros: Automatic TLS certificate management and HTTP-to-HTTPS redirects are enabled by default.
• Pros: Reverse proxy support covers HTTP, HTTPS, WebSockets, gRPC, and FastCGI, with load balancing and health checks.
• Pros: Supports multiple configuration methods, deployment models, and DNS challenge providers.
• Pros: The software is free, and paid sponsorships do not paywall features.
• Cons: Response caching is not listed as supported.
• Cons: The more extensive support and service options require paid sponsorships, including high monthly price tiers.

Alternatives

For other tools to consider, compare NGINX, Traefik Proxy, and Envoy Proxy. The category also includes ngrok, Pomerium, freenginx, F5 BIG-IP APM, and Roslynator.

Verdict

Caddy brings automatic HTTPS, broad reverse proxy protocol support, multiple configuration choices, and varied deployment options into a free self-hosted server platform. Its strongest fit is for operators who want certificate handling built into the server and value flexibility in how it is configured and deployed. The main caveat is that caching is not listed, and organizations wanting dedicated assistance or guaranteed response times must look to sponsorship plans whose prices range from $25 a month to $11,900 a month.