Michael Pope
PosternProxy

PosternProxy is my dual-license reverse proxy management platform built on Caddy. It is designed to make proxy infrastructure easier to operate without hiding the underlying engineering: route traffic, automate TLS, manage proxy hosts, and control multiple servers from one focused web interface.

The project is currently in beta and follows a two-path licensing model: a complete AGPLv3 open-source core for community and self-hosted use, with commercial licensing available for organizations that need non-AGPL rights, SaaS/MSP/OEM use, priority support, or custom engineering.

Why I Am Building It

Reverse proxies are critical infrastructure, but managing them often turns into scattered config files, manual certificate handling, unclear ownership, and risky one-off changes. Caddy solves much of the hard proxy and TLS work, but teams still need an approachable control plane for day-to-day operations.

PosternProxy is built to be that control plane.

The goal is to give infrastructure teams a clear way to:

  • Publish internal and external services
  • Route traffic to upstream applications
  • Automate HTTPS with Let’s Encrypt
  • Manage multiple proxy servers from one UI
  • Track host health and request behavior
  • Keep configuration history and audit trails
  • Run the stack self-hosted under their own control

Dual-License Model

PosternProxy is open by default and commercially flexible when business requirements demand it.

The community path uses AGPLv3, making the complete controller and agent available for individuals, homelabs, and organizations comfortable with AGPL obligations for network-served software.

The commercial path is for teams that need legal flexibility to embed, host, redistribute, or build proprietary offerings with PosternProxy. That path is intended for SaaS providers, MSPs, OEM-style use cases, and organizations that need support agreements or custom engineering.

This model fits the kind of infrastructure software I want to build: transparent enough to inspect and self-host, but structured enough to sustain long-term maintenance.

What It Does

PosternProxy turns Caddy into a production-ready reverse proxy platform with an operational UI and management layer.

Key capabilities include:

  • Proxy host management for domains, upstreams, redirects, custom headers, and parked domains
  • Automatic HTTPS through Caddy and Let’s Encrypt
  • Custom certificate support for uploaded PEM certificates
  • Host health monitoring with live status, request totals, failure counts, and automatic refresh
  • Multi-server management using secure outbound agents
  • Per-host access controls including IP allowlists, denylists, and HTTP Basic Auth
  • Custom error pages for 404, 502, and 503 responses
  • Configuration history and rollback for safer changes
  • API tokens for scripts, CI/CD, and operational automation
  • Nginx import preview, backups, and restore workflows
  • Layer 4 TCP/UDP forwarding and TLS passthrough support

The product is built around the practical work of running services, from configuration through day-to-day operations.

Architecture

The stack is intentionally small:

  • A Go controller
  • Embedded Vue UI
  • SQLite database
  • Caddy as the data plane
  • Optional remote agents for multi-server management

The controller bundles the UI, API, and database into one deployable binary. Caddy handles the traffic plane, while agents can extend control to additional servers without requiring inbound management ports on those nodes.

That architecture keeps deployment understandable while still supporting serious infrastructure workflows.

Engineering Themes

PosternProxy reflects several ideas I care about in infrastructure tooling:

  • Operational clarity: administrators should understand what is routed, where it goes, and whether it is healthy
  • Secure defaults: TLS automation, access controls, audit logs, and scoped API tokens should be part of the product model
  • Self-hosted control: teams should be able to run it on their own infrastructure
  • Simple deployment: Docker and native Linux deployment paths should both be supported
  • Reversible change: configuration history and rollback reduce operational risk
  • Commercial sustainability: the licensing model should support ongoing development without closing the core

Why It Belongs In My Portfolio

PosternProxy is a product-scale infrastructure project. It combines systems engineering, web application design, security controls, deployment packaging, documentation, licensing strategy, and practical operations experience.

It also reflects the kind of engineering I want to be known for: making powerful infrastructure approachable without making it opaque.