Key Points

Redis has received a pull request that adds a new data type: arrays, along with many new array-oriented commands (e.g., ARCOUNT, ARLEN, ARGET/ARSET, and others).
An interactive “Redis Array Playground” was built in a web-based WASM-compiled subset of Redis to let users try the new array commands safely in the browser.
The new command ARGREP is highlighted as particularly interesting because it performs server-side “grep”-style matching across a range of array values using the vendored TRE regex library.
The article points readers to further details from Salvatore on the (including AI-assisted) development process behind the Redis array type.

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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