What is a proxy server?
Corbin Brown
2 min read
Part of the Vibe Coding Fundamentals video series on YouTube.
A proxy server is a middleman: instead of you talking to a website directly, you talk to the proxy, and the proxy talks to the website on your behalf. The website sees the proxy, not you. That's the entire concept (someone running your errand so the shop never sees your face) and an unreasonable amount of the internet is built out of this one move.
The same trick, worn four ways
- VPNs: your traffic exits from the VPN's machine, so websites see its location and identity instead of yours. Privacy via middleman.
- Corporate and school networks: all traffic funnels through their proxy, which filters and logs it. Control via middleman.
- Reverse proxies: the one builders actually own: a middleman standing in front of a server instead of a user. Cloudflare is exactly this: visitors talk to it, it talks to your site, and it absorbs attacks and serves cached copies along the way.
- Your own app's API routes: when your app calls OpenAI from its server instead of the browser, so the API key never ships to users. Your server is acting as a proxy between your users and OpenAI. Agents build this pattern constantly; now you know its name.
When it touches your project
Three moments. An agent says “we'll proxy that request”. It means routing a call through your server, usually to hide a key or dodge a browser restriction called CORS (a security rule that blocks browsers from calling other people's APIs directly; the proxy is the standard answer). You put Cloudflare in front of your site: you've deployed a reverse proxy. Or you're debugging why an office network breaks your app: their proxy is rewriting or blocking something. In all three, the mental model is identical: find the middleman, and you've found the explanation.
FAQ
Proxy vs VPN: same thing?
A VPN is a proxy with stronger wrapping: it encrypts everything between you and the middleman, not just browser traffic. For “hide my location from a website,” they're the same idea at different strengths.
Do I need to set up a proxy for my app?
You probably already have two without noticing: your hosting platform terminates traffic in front of your code, and any server-side API call your agent wrote is proxying for your users. Deliberately adding more is a scaling-era problem, not a starting one.