Vintage fun: Prodding AI agents using retro hardware just because you can

What happened

AWS developer advocate Darko Mesaroš connected a DECwriter teletype to AWS Kiro, an AI coding service that works from a command line. He can type to the AI and read its replies on paper, like an old-style computer terminal. He built a small Rust program to make the AI's output fit the old machine.

Key facts

• The teletype prints about 30 characters per second.
• A WiModem232 device connects the teletype using the Hayes modem standard.
• The project uses Agent Client Protocol (ACP) to talk to Kiro.
• The teletype's heyday ended about 40 years ago.

How it works

The teletype needs a serial connection, which is an old way of sending data one bit at a time. The WiModem232 acts like an old Hayes-compatible modem, a device that was once used to connect home computers to online bulletin boards. Kiro's normal output is too busy for a slow printer, so a Rust program trims it into plain text that the teletype can handle.

Why it matters

The project is more of a hobby stunt than a useful tool. Still, it shows that AI tools can work with many kinds of software when they follow shared standards like ACP. The builder says the same setup could work with other coding assistants, such as Claude Code or Codex. It also shows how much skill a project like this needs, including coding, containers, and protocols.

Things to know

• The setup does not handle lost data packets. If data is dropped, it is gone.
• There is no buffering, so the slow serial device is the bottleneck.
• The code is public and built for Kiro, but the builder says it can be adapted.