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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.

Screenshot of a Redis command builder UI. Left sidebar shows commands ARSCAN, ARSEEK, ARSET. Main panel has a "predicate oneof" section with a MATCH dropdown and value CHERRY, plus a "+ add another" button. Below is "options (optional) oneof" with checkboxes: AND (checked), OR (unchecked), LIMIT (checked, value 10), WITHVALUES (checked), NOCASE (checked). COMMAND section shows: ARGREP myarr - + MATCH CHERRY AND LIMIT 10 WITHVALUES NOCASE. A red "Run command" button is below. REPLY section shows "(no reply yet)".

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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