Tool: Redis Array Playground
Simon Willison’s Weblog
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4th May 2026
Tool
Redis Array Playground — # Redis Array Playground
Salvatore Sanfilippo submitted a PR adding a new data type - arrays - to Redis.
The new commands are ARCOUNT, ARDEL, ARDELRANGE, ARGET, ARGETRANGE, ARGREP, ARINFO, ARINSERT, ARLASTITEMS, ARLEN, ARMGET, ARMSET, ARNEXT, AROP, ARRING, ARSCAN, ARSEEK, ARSET.
The implementation is currently available in a branch, so I had Claude Code for web build this interactive playground for trying out the new commands in a WASM-compiled build of a subset of Redis running in the browser.
The most interesting new command is ARGREP which can run a server-side grep against a range of values in the array using the newly vendored TRE regex library.
Salvatore wrote more about the AI-assisted development process for the array type in Redis array type: short story of a long development.
Posted 4th May 2026 at 3:53 pm
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This is a beat by Simon Willison, posted on 4th May 2026.
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