What it is
Apache HTTP Server is an industry veteran operating on a process or thread-based model (MPM). Caddy is a modern server written in Go, focused on simplicity and out-of-the-box security automation.
| Parameter | Apache | Caddy |
|---|---|---|
| Language | C | Go |
| TLS Management | Manual / Certbot | Automatic (built-in) |
| Configuration | .conf / .htaccess directives | Caddyfile / JSON API |
| Architecture | Process/Thread-based | Event-driven / Goroutines |
| Binary | OS-dependent libraries | Static (single file) |
Performance
Apache with MPM Event shows stable performance under load, but RAM consumption grows linearly with the number of connections. In static content benchmarks, Apache lags behind Go-based solutions and Nginx. Caddy utilizes lightweight goroutines, allowing it to handle tens of thousands of concurrent connections with lower RAM usage (averaging 30-50% less than Apache in Prefork mode). However, in specific tasks like heavy CGI script processing, the difference is minimized by the execution time of the script itself.
Configuration & complexity
Apache configuration requires a deep understanding of syntax and module structure. A typical VirtualHost takes 15-20 lines. Caddy uses Caddyfile, where a reverse proxy is configured in one line:
example.com {
reverse_proxy localhost:8080
}Key differentiator: Caddy automatically obtains and renews Let's Encrypt or ZeroSSL certificates without external utilities like Certbot.
When to choose what
- Apache: if you need
.htaccesssupport (shared hosting), integration with legacy modules (mod_perl, mod_php), or complex filesystem-level routing. - Caddy: for microservices, rapid local development environment setup, automating thousands of domains, and running in Docker containers where minimal size and zero dependencies are vital.
Cost / licensing
Both technologies are distributed under the Apache License 2.0. This allows free use in commercial projects, code modification, and distribution of derivative products without mandatory open-sourcing.
Ecosystem & integrations
Apache has the most extensive module base accumulated over 25 years. Native support for any OS and integration with control panels (cPanel, ISPmanager) is standard. Caddy offers a modular system via the xcaddy tool. Plugins allow extending functionality (e.g., DNS provider support for Wildcard certificates), but their number is significantly lower than Apache's.
Verdict
Apache remains the choice for enterprise systems with legacy code and specific module requirements. Caddy is the optimal choice for modern web applications where HTTPS setup speed and infrastructure maintenance simplicity are critical.