Musk Says Grok Translates Posts. The Code Says Otherwise.

On March 29, 2026, Elon Musk said something was working on X. "Grok automatically translating and recommending 𝕏 posts from other languages is starting to work," he posted. The implication was clear: X's AI was now routing non-English content into English-speaking users' feeds, powered by Grok.

The only problem is that the published algorithm contains no translation component at all.

X open-sourced its recommendation system — named Phoenix, built on a Transformer architecture — in January 2026 at github.com/xai-org/x-algorithm. The codebase is Rust-based, organized around four components: Home Mixer handles feed orchestration, Thunder manages in-memory post storage, Phoenix performs Grok-based ranking using a two-tower model, and the Candidate Pipeline sources content for evaluation. A review of the repository shows no module, no pipeline stage, and no routing logic that handles translation or cross-lingual content routing. The architecture describes a ranking system — not a translation system.

This is the gap at the center of Musk's announcement. Either the translation-to-recommendation pipeline exists in a non-public layer, or the recommendation engine isn't involved in the way the claim implies. X did not respond to a request for comment on how translated posts enter the ranking pipeline.

The distinction matters because X's For You feed operates through a specific architecture. Phoenix, the Grok-based ranking component, uses a two-tower model to analyze user behavior — including likes, replies, time spent viewing posts, blocks, and mutes — to score how likely a user is to engage with a given post, according to technical summaries of the system. Content is also surfaced through SimClusters, a system of roughly 145,000 topic clusters, and social graph signals. The result: roughly half of the content in the For You feed comes from accounts a user doesn't follow. That's the routing surface Musk is describing when he says Grok is "recommending" translated posts. Where translation fits into that ranking logic is not visible in the published code.

There is also the separate question of what Grok's auto-translation product actually does. Grok does not perform faithful, word-for-word conversion. It generates summaries and adds interpretive content, a process one guide to the feature described as "a creative rewrite rather than a faithful conversion" that "frequently alters the tone and meaning of the original message without warning." That matters for a recommendation context: a post reaching new audiences through Grok isn't being relayed — it's being recomposed. The AI can add context the original author didn't provide, in a language the author may not speak.

Consent is opt-out rather than opt-in. X enabled the feature by default. Users who want to stop their posts from being translated must manually disable it via Settings > Accessibility > Languages > Show Grok translation, according to guides on the feature. The translation product is real. Whether it feeds into the recommendation system the way Musk describes is not something the open-source architecture answers.

On March 26, 2026, Nikita Bier, X's head of product, called the coming Grok algorithm integration "the most important change we have done on X." The framing was about Grok's ranking power replacing a prior 48-million-parameter model — not about translation. Benji Taylor, formerly chief product officer at the DeFi protocol Aave and design lead at Coinbase's Base layer, was announced the day before as design lead for both X and xAI. The corporate structure adds its own context: xAI acquired X in March 2025. SpaceX acquired xAI in February 2026. What Musk is describing as a product achievement sits inside a company that has completed two major acquisitions in under a year.

The Grok translation feature — enabled by default, generating summaries rather than translations, with no visible integration into the recommendation pipeline — is either doing more than the published code shows, or the public claims are running ahead of the architecture. The code is the most direct evidence available, and it doesn't show what Musk says it shows.