- Location
- San Francisco, CA, United States · Remote
- Compensation
- Not stated in this snapshot
- Employment
- Contract
- Experience level
- MID (2–5 years exp)
- Specialization
- Founder, Wellfound
- Source
- Wellfound
Looking for a CTO CoFounder
New Exciting App & Tech Business (B2C)
- OpenAI Whisper large-v3 for speech-to-text with word-level timestamps
- wav2vec2 (HuggingFace) for phoneme sequence extraction from user audio
- Weighted Levenshtein distance comparison against pre-computed reference phoneme sequences
- Async processing via Redis job queue — UI never blocks waiting for results
- GPT-4o feedback generator: 2–3 sentence natural coaching tip per attempt, cached per phoneme diff pattern
Required skills — must have all of these
- Python 3.10+ and FastAPI
- Machine learning / NLP: HuggingFace models, wav2vec2, audio processing (librosa or equivalent)
- React Native with Expo (specifically Expo AV, Expo Camera, Reanimated 3)
- FFmpeg WASM — on-device media processing
- Deep linking: Branch.io or equivalent
- PostgreSQL and Supabase (including realtime subscriptions)
- Redis — sorted sets for leaderboards
- Third-party API integration: OpenAI (Whisper + GPT-4o), ElevenLabs, Stripe, Clerk, Branch.io
- AWS S3 for audio and media storage
- REST API design with full documentation
- Git — all code in product owner's GitHub from day one
Nice to have
- Prior experience with audio or speech technology products
- Experience with viral sharing mechanics or social app features
- Docker for containerising the Python backend
- Familiarity with phonetics or linguistics