Flower Intelligence runs models on device, with remote handoff off by default
Flower Labs released Flower Intelligence on March 12, 2025 as a preview, an open source inference library that runs a language model on the user’s own device and only moves the work to a remote service if the app and the user allow it. The company shipped SDKs for Swift and TypeScript, and the TypeScript build defaults to Llama 3.2 1B in 16-bit precision.
The library picks a local engine from the environment it finds itself in. The TypeScript package depends on MLC’s WebLLM, which executes models in the browser through WebGPU, and on Hugging Face transformers.js, which it uses when the code runs under Node.js rather than in a page. The Swift package is built on MLX Swift and Hugging Face swift-transformers, and declares iOS 16 and macOS 14 as its minimum platforms, so local inference on Apple hardware goes through MLX.
Flower Labs’ model reference covers Llama 3.2 at 1B and 3B, Llama 3.1 8B, SmolLM2 at 135M, 360M and 1.7B, and DeepSeek R1 Distill Llama 8B, most of them as 4-bit builds. Which of those run on device depends on the backend. Node.js is limited to the 1B and SmolLM2 entries, while the 8B models run only in the browser and on the MLX Swift path, and Llama 3.2 3B in 16-bit is MLX Swift only.
Remote handoff is off by default. An application has to set the remoteHandoff property and supply an API key before the library will contact Flower Confidential Remote Compute, and even with both in place a chat call tries a local engine first and retries remotely only when no local engine matches the model or the local run fails. Individual requests can be pinned with forceLocal or forceRemote. Flower Labs describes the remote service as a private extension of the device that costs the developer no extra work, and named Mozilla Thunderbird as an early adopter building its Thunderbird Assist feature on the library. Ryan Sipes, Managing Director for Mozilla Thunderbird, tied that choice to the mail client’s user base in the announcement.
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Both SDKs are published under the Apache 2.0 license, the TypeScript one as @flwr/flwr on npm and the Swift one as a package in the Flower repository. Flower Labs called the release inference-only and listed fine-tuning, RAG and pre-training as later steps, with the remote compute service available on application for early access.