HNHacker News
TopNewBestAskShowJobs

rshemet

43 karma · joined August 6, 2022

submissionscomments
rshemet··on Whistle: Speech to Text in 16.9 MB
hey, Roman here from Cactus, thank you for the feature!

opening this thread for questions/feedback if you have any

rshemet··on Show HN: Needle2: 14MB agentic LLM for phones, wearables, smart home and robots
Did you give it a tool to increase temperature, or only one that sets temperature to an absolute value?

Either way, setting temperature to 5° is obviously wrong - even if it knew the current temperature - but models of this size can't reason about relative values very well.

Give it a tool to change temperature by a given amount, and see what happens!

rshemet··on Show HN: Needle2: 14MB agentic LLM for phones, wearables, smart home and robots
hey Kenny, Roman from Cactus here -

could you say more? What kind of home assistant / what stack

rshemet··on Show HN: Needle2: 14MB agentic LLM for phones, wearables, smart home and robots
it stands for Lets-not-be-sarcastic :)
rshemet··on Show HN: Needle2: 14MB agentic LLM for phones, wearables, smart home and robots
Roman from Cactus here -

yes you're right, there's only so much a 14MB model can do.

Needle excels at in-conext inference, with tightly defined environments. In our experience:

accurate descriptions + narrow tool scope = success

rshemet··on Show HN: Needle2: 14MB agentic LLM for phones, wearables, smart home and robots
there are android binaries you can ship in your own app - https://huggingface.co/Cactus-Compute/needle2/tree/main

but if you're just looking for somewhere to try the model, use our in-browser playground! - https://cactuscompute.com/needle

rshemet··on Show HN: Needle2: 14MB agentic LLM for phones, wearables, smart home and robots
Hey! Roman here from Cactus - yes, we're putting putting together a detailed guide for ESP32.

In the meantime, if you have enough RAM for the current model (≈28MB), our repo will get you up & running:

https://github.com/cactus-compute/needle

rshemet··on Launch HN: Cactus (YC S25) – AI inference on smartphones
Yes! Cactus is optimized for mobile CPU inference and we're finishing internal testing of hybrid kernels that use the NPU, as well other chips.

We don't advise using GPUs on smartphones, since they're very energy-inefficient. Mobile GPU inference is actually the main driver behind the stereotype that "mobile inference drains your battery and heats up your phone".

Wrt to your last question – the short answer is yes, we'll have multimodal support. We currently support voice transcription and image understanding. We'll be expanding these capabilities to add more models, voice synthesis, and much more.

rshemet··on Launch HN: Cactus (YC S25) – AI inference on smartphones
indeed, this is exactly the goal! The license grants rights to commercial use, unlocks additional hardware acceleration, includes cloud telemetry, and offers significant savings over using cloud APIs.

In our deployments, we've seen open source models rival and even outperform lower-tier cloud counterparts. Happy to share some benchmarks if you like.

Our pricing is on a per-monthly-active-device basis, regardless of utilization. For voice-agent workflows, you typically hit savings as soon as you process over ≈2min of daily inference.

rshemet··on Gemma 3 270M: Compact model for hyper-efficient AI
you can run it in Cactus Chat (download from the Play Store)
rshemet··on Gemma 3 270M: Compact model for hyper-efficient AI
you can also run it on Cactus - either in Cactus Chat from the App/Play Store or by using the Cactus framework to integrate it into your own app
rshemet··on Show HN: OWhisper – Ollama for realtime speech-to-text
THIS IS THE BOMB!!! So excited for this one. Thanks for putting cool tech out there.
rshemet··on I want everything local – Building my offline AI workspace
if you ever end up trying to take this in the mobile direction, consider running on-device AI with Cactus –

https://cactuscompute.com/

Blazing-fast, cross-platform, and supports nearly all recent OS models.

rshemet··on Show HN: Cactus – Ollama for Smartphones
https://play.google.com/store/apps/details?id=com.rshemetsub...
rshemet··on Show HN: Cactus – Ollama for Smartphones
thank you! Very kind feedback, and we'll add your feedback to our to-dos.

re: "question would get stuck on the last phrase and keep repeating it without end." - that's a limitation of the model i'm afraid. Smaller models tend to do that sometimes.

rshemet··on Show HN: Cactus – Ollama for Smartphones
say more about "community tools"?
rshemet··on Show HN: Cactus – Ollama for Smartphones
in the app you mean?

Adding shortly!

rshemet··on Show HN: Cactus – Ollama for Smartphones
that's our mission! if you are passionate about the space, we look forward to your contributions!
rshemet··on Show HN: Cactus – Ollama for Smartphones
no, good observation - not hidden; we don't have a "clear conversation" button.

to your previous point - Cactus fully supports tool calling (for models that have been instruction-trained accordingly, e.g. Qwen 1.7B)

for "turning your old phones into local llm servers", Cactus is likely not the best tool. We'd recommend something like actual Ollama or Exo

rshemet··on Show HN: Cactus – Ollama for Smartphones
looking forward to your feedback!
rshemet··on Show HN: Cactus – Ollama for Smartphones
hot off the press in our latest feature release :)

we support cloud fallback as an add-on feature. This lets us support vision and audio in addition to text.

rshemet··on Show HN: Cactus – Ollama for Smartphones
great observation - this data is not from a controlled environment; these are metrics from our Cactus Chat use (we only collect tok/sec telemetry).

S25 is an outlier that surprised us too.

I got $10 on S25 climbing back up to the top of the rankings as more data comes in :)

rshemet··on Show HN: Cactus – Ollama for Smartphones
thank you! We're continue to add performance metrics as more data comes in.

A Qwen 2.5 500M will get you to ≈45tok/sec on an iPhone 13. Inference speeds are somewhat linearly inversely proportional to model sizes.

Yes, speeds are consistent across frameworks, although (and don't quote me on this), I believe React Native is slightly slower because it interfaces with the C++ engine through a set of bridges.

rshemet··on Show HN: Cactus – Ollama for Smartphones
Great question. Currently, each app is sandboxed - so each model file is downloaded inside each app's sandbox. We're working on enabling file sharing across multiple apps so you don't have to redownload the model.

With respect to the inference SDK, yes you'll need to install the (react native/flutter) framework inside each app you're building.

The SDK is very lightweight (our own iOS app is <30MB which includes the inference SDK and a ton of other stuff)

rshemet··on Show HN: Cactus – Ollama for Smartphones
reminds me of

- "You are, undoubtedly, the worst pirate i have ever heard of" - "Ah, but you have heard of me"

Yes, we are indeed a young project. Not two weeks, but a couple of months. Welcome to AI, most projects are young :)

Yes, we are wrapping llama.cpp. For now. Ollama too began wrapping llama.cpp. That is the mission of open-source software - to enable the community to build on each others' progress.

We're enabling the first cross-platform in-app inference experience for GGUF models and we're soon shipping our own inference kernels fully optimized for mobile to speed up the performance. Stay tuned.

PS - we're up to good (source: trust us)

rshemet··on Show HN: Cactus – Ollama for Smartphones
love this. So many layers deep, we just had a good laugh.
rshemet··on Show HN: Cactus – Ollama for Smartphones
Very good point - we've heard this before.

We're restructuring the model initialization API to point to a local file & exposing a separate abstracted download function that takes in a URL.

wrt downloading post-install: based on our feedback, this is indeed a preferred pattern (as opposed to bundling in large files).

We'll update the download API, thanks again.

rshemet··on Show HN: Cactus – Ollama for Smartphones
True - but Cactus is not just an app.

We are a dev toolkit to run LLMs cross-platform locally in any app you like.

rshemet··on Show HN: Cactus – Ollama for Smartphones
Thanks for the feedback. You're right to point out that Google AI Edge is cross-platform and more flexible than our phrasing suggested.

The core distinction is in the ecosystem: Google AI Edge runs tflite models, whereas Cactus is built for GGUF. This is a critical difference for developers who want to use the latest open-source models.

One major outcome of this is model availability. New open source models are released in GGUF format almost immediately. Finding or reliably converting them to tflite is often a pain. With Cactus, you can run new GGUF models on the day they drop on Huggingface.

Quantization level also plays a role. GGUF has mature support for quantization far below 8-bit. This is effectively essential for mobile. Sub-8-bit support in TFLite is still highly experimental and not broadly applicable.

Last, Cactus excels at CPU inference. While tflite is great, its peak performance often relies on specific hardware accelerators (GPUs, DSPs). GGUF is designed for exceptional performance on standard CPUs, offering a more consistent baseline across the wide variety of devices that app developers have to support.

rshemet··on Show HN: Cactus – Ollama for Smartphones
So far, our focus is on supporting models with fully open-sourced weights. Providers who are sensitive about their weights typically lock those weights up in their cloud and don't run their models locally on consumer devices anyway.

I believe there are some frameworks pioneering model encryption, but i think we're a few steps away from wide adoption.

Page 1 of 2Next →