Build with Voice x Hackathon
Build with voice. Move fast. Push what’s possible.
Join us in London for a weekend at the frontier of human–AI interaction. In just 48 hours, go from blank page to working prototype — powered by ElevenLabs, Synthflow, and Anam.ai.
Hosted by Antler, the global VC backing founders from day zero, this hackathon is for those ready to experiment, collaborate, and create the future of voice.
👤 Who we’re looking for
We’re curating a highly selective group of exceptional builders:
Engineers, product thinkers, designers, and creatives — all builders welcome
Aspiring founders exploring voice, audio, and applied AI
High-agency operators ready to collaborate and move fast
No team? No idea yet? No problem. Teams will form on Day 1.
Apply by midnight Thursday 4 September. Places are limited.
⚡ What you’ll get
ElevenLabs: Access to powerful voice APIs, credits, and tools
Synthflow: Access to the platform for building human-like phone agents with memory, context, and real-time responses in 30+ languages
Anam.ai: One-shot persona synthesis to bring characters and voices to life
Mentorship from the ElevenLabs, Synthflow, Anam, and Antler teams, plus more partners to be announced
Workspace, fuel, and pizza + drinks each evening
A chance to demo to top operators, investors, and product minds in AI
🏆 Prizes
£1,000 cash for the most innovative build
ElevenLabs credits for the most unhinged creation
Bragging rights for the project most likely to hit #1 on Product Hunt
Winning teams are fast-tracked into interviews for Antler’s Autumn 2025 residency (kicking off 7 October)
📍 Logistics
Dates:
Saturday 6 September, 11 AM – 9 PM
Sunday 7 September, 9 AM – 5 PM
Location: Central London (shared after registration)
Format: In-person only
Food & drinks: Provided
About the Partners
Synthflow
Synthflow is a voice AI platform for creating phone agents that sound human, remember context, and route calls intelligently. Agents plug directly into CRMs, telephony, and internal tools, combining memory with real-time responses in 30+ languages at under 500 ms latency. Built to scale in minutes with no-code or APIs, Synthflow delivers enterprise-grade automation at transparent pricing from £0.06/minute.
Anam.ai gives developers the power to drop a photorealistic AI persona into any web app with just 5 lines of code. These real-time avatars stream live audio and video via WebRTC, powered by customizable prompts, voices, and LLMs. Build AI that feels human and talks back, fast.
ElevenLabs
Generate lifelike spoken audio with AI tools. Discover top-quality voices at ElevenLabs. Realistic, high-quality AI audio generation. Make your content resonate with ElevenLabs.