Composer was built by Cursor (now part of SpaceXAI). Elon Musk's AI company building the Grok series of models. Founded in 2023 as xAI, now part of SpaceX. Cursor (Anysphere) and its Composer coding models were acquired in 2026 and are tracked here.

Is Composer open source?

No. Composer is a closed model. The weights are not published — it is available only through the provider's own API, apps, or partner platforms.

What came before and after Composer?

SpaceXAI's previous tracked release was Grok 4 Fast on Sep 19 2025, 40 days earlier. It was followed by Grok 4.1 on Nov 17 2025.

Composer

Released Oct 29 2025

Composer is an AI model released by Cursor (now part of SpaceXAI) on Wednesday, Oct 29 2025, 40 days after Grok 4 Fast.

Compare Composer with

Composer

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Frequently asked questions

: Composer was released by Cursor (now part of SpaceXAI) on Wednesday, Oct 29 2025.
: Composer was built by Cursor (now part of SpaceXAI). Elon Musk's AI company building the Grok series of models. Founded in 2023 as xAI, now part of SpaceX. Cursor (Anysphere) and its Composer coding models were acquired in 2026 and are tracked here.
: No. Composer is a closed model. The weights are not published — it is available only through the provider's own API, apps, or partner platforms.
: SpaceXAI's previous tracked release was Grok 4 Fast on Sep 19 2025, 40 days earlier. It was followed by Grok 4.1 on Nov 17 2025.