Hacker NewsFriday · May 22, 2026FREE

Show HN: Rmux – A programmable terminal multiplexer with a Playwright-style SDK

Rmux, a new programmable terminal multiplexer, was introduced on Hacker News on May 21, 2026. Unlike traditional terminal multiplexers like tmux or screen, Rmux integrates a Playwright-style SDK, providing a high-level API for scripting and automating terminal sessions. This SDK allows developers to programmatically control terminal panes, send input, capture output, and manage multiple concurrent shell environments from a single script. The design aims to simplify the automation of complex command-line workflows, making it easier to build reproducible development environments, run automated tests against CLI applications, or orchestrate multi-step deployment processes. The Playwright-style SDK offers familiar patterns for those accustomed to browser automation tools, translating concepts like element selection and interaction into the terminal context. This approach enables more robust and less brittle automation scripts compared to relying solely on shell scripting or expect-like tools, which often struggle with dynamic terminal outputs or complex interactive prompts. By abstracting away the low-level details of terminal interaction, Rmux allows developers to focus on the logic of their automation tasks. This includes scenarios like setting up complex development environments, orchestrating multi-service applications, or performing end-to-end testing of command-line interfaces. The project's "Show HN" debut suggests it is an early-stage but functional tool designed to address a specific need for more sophisticated terminal automation.