This repository implements 'lego', a production-grade ACME client written in Go for automating SSL/TLS certificate issuance and renewal with Let's Encrypt and other ACME-compliant Certificate Authorities. The system operates as both a CLI tool and a reusable library, supporting the full ACME protocol (RFC 8555) including account registration, order creation, challenge solving (HTTP-01, DNS-01, TLS-ALPN-01, and experimental DNS-PERSIST-01), certificate download, and lifecycle management (renewal, revocation, archival). Architecturally, the codebase is modular: a core ACME API client (`acme/api/`) handles protocol interactions; challenge solvers (`challenge/`) implement domain validation strategies; a plugin-style DNS provider system (`providers/dns/`) integrates with over 200 DNS service APIs for automated DNS-01 challenge resolution; a CLI layer (`cmd/`) provides subcommands for run, certificates, accounts, archives, and migration; and storage (`cmd/internal/storage/`) persists certificates, keys, and account data to disk. Configuration is via YAML files, environment variables, and dotenv files. Key entry points include `main.go` (application start), `cmd/cmd_root.go` (CLI root command), and `lego/client.go` (library entry point). The primary data flow involves the user specifying domains and challenge type, the client interacting with the ACME CA to create orders and solve challenges (e.g., creating a DNS TXT record via a provider API), and finally downloading and storing the issued certificate. External dependencies include the ACME CA servers, the DNS provider APIs, and optionally an HTTP server for HTTP-01 challenges. The codebase demonstrates strong engineering practices with extensive unit and end-to-end testing, a consistent provider interface, and several well-designed internal utilities (HTTP mock server, retry/polling, error wrappers). However, the large number of DNS providers introduces boilerplate duplication and potential API drift, and the project uses a custom Go-like language dialect that may pose tooling and onboarding risks.
WireHole is a Docker Compose project that combines WireGuard, Pi-hole, and Unbound to create a private VPN with ad-blocking and recursive DNS resolution. It is not a software library but an infrastructure deployment template. The stack provides a VPN server, DNS filtering through Pi-hole, and private DNS resolution via Unbound, all running in containers. The project is designed for easy deployment on a Linux server, with a focus on security (e.g., web interfaces bound to localhost, minimal container capabilities, strong password generation). It supports two VPN backends: wg-easy (with a web UI) and linuxserver/wireguard (configuration-file based). The codebase consists of shell scripts for setup, migration, and diagnostics, along with CI/CD pipelines, test suites, and detailed documentation. The project demonstrates high operational maturity with comprehensive tests, pinning of image versions, and a doctor script for troubleshooting. While it is not a reusable software library, its scripts and configuration patterns are well-crafted and could serve as templates for similar Docker Compose deployments.