Context

• Cactus (YC S25) is a low-latency engine for mobile devices & wearables.
• Cactus runs locally on edge devices with hybrid routing of complex tasks to cloud models like Gemini.
• Google DeepMind just released Gemma 4, the first on-device model you can voice-prompt.
• Gemma 4 on Cactus is multimodal, supporting voice, vision, function calling, transcription and more!

Challenge

• All teams MUST build products that use Gemma 4 on Cactus.
• All products MUST leverage voice functionality in some way.
• All submissions MUST be working MVPs capable of venture backing.
• Winner takes all: Guaranteed YC Interview + GCP Credits.

Special Tracks

• Best On-Device Enterprise Agent (B2B): Highest commercial viability for offline tools.
• Ultimate Consumer Voice Experience (B2C): Best use of low-latency compute to create ultra-natural, instantaneous voice interaction.
• Deepest Technical Integration: Pushing the boundaries of the hardware/software stack (e.g., novel routing, multi-agent on-device setups, extreme power optimization).

Prizes per special track:

• 1st Place: $2,000 in GCP credits
• 2nd Place: $1,000 in GCP credits
• 3rd Place: $500 in GCP credits

Judging

• Rubric 1: The relevnance and realness of the problem and appeal to enterprises and VCs.
• Rubric 2: Correcness & quality of the MVP and demo.

Setup (clone this repo and hollistically follow)

• Step 1: Fork this repo, clone to your Mac, open terminal.
• Step 2: git clone https://github.com/cactus-compute/cactus
• Step 3: cd cactus && source ./setup && cd .. (re-run in new terminal)
• Step 4: cactus build --python
• Step 5: cactus download google/functiongemma-270m-it --reconvert
• Step 6: Get cactus key from the cactus website
• Sept 7: Run cactus auth and enter your token when prompted.
• Step 8: pip install google-genai (if using cloud fallback)
• Step 9: Obtain Gemini API key from Google AI Studio (if using cloud fallback)
• Step 10: export GEMINI_API_KEY="your-key" (if using cloud fallback)

Next steps

1. Read Cactus docs carefully: Link
2. Read Gemma 4 on Cactus walkthrough carefully: Link
3. Cactus & DeepMind team would be available on-site.

Submissions

1. Record a 60s demo video
2. Submnit here by 11am
3. NO multiple submissions!