Founding Fullstack Engineer — Build AI-Driven Dating Stack

Praxis, Inc.; San Francisco (CA); On-site; USD 180,000 - 280,000; Full time

Job summary

Praxis, Inc. is seeking a technical co-founder to own the full stack for Known, a consumer AI dating product built from the ground up with a focus on delightful UI, robust data flows, and seamless integrations.

You will partner with AI/ML, product, and design teams to translate ambitious ideas into production code, shaping millions of user experiences and leading critical architectural decisions.

Qualifications

• 3-5 years building production fullstack or mobile applications, ideally in consumer products or startups.
• Strong proficiency in TypeScript, React, React Native, and Node.js
• Experience designing and scaling RESTful APIs with attention to performance, security, and maintainability.
• Strong working knowledge of Postgres - you're comfortable with data modeling, queries, indexes, and database performance.
• Experience with cloud platforms (AWS, GCP, Vercel, Railway) for deployment and infrastructure.
• Comfortable with modern development workflows: Git, CI/CD, feature flags, monitoring, and incident response.
• Familiarity with WebSockets and WebRTC for real-time communication is a plus.
• Passion for user experience and product quality - you'll care about polish, speed, and edge cases.

Responsibilities

• Build and ship mobile experiences in React Native that are fast, delightful, and accessible - from onboarding flows to real-time messaging and match discovery.
• Design and maintain backend services in Node.js/TypeScript, including RESTful APIs, WebSocket connections for real-time chat, and WebRTC integrations for audio/video experiences.
• Integrate third-party platforms (OpenAI/Anthropic LLMs, Apple/Google Pay, reservation systems, SMS/push notifications) to deliver seamless, automated experiences.
• Collaborate with AI/ML engineers to surface model outputs - compatibility scores, personalized recommendations, conversational agents - through intuitive UI and performant APIs.
• Own infrastructure and deployment using modern cloud platforms, ensuring reliability, security, and scalability as we grow.
• Implement analytics and instrumentation to measure user engagement, conversion funnels, and product health in real time.

Skills

TypeScript

React

React Native

Node.js

RESTful APIs

WebSockets

WebRTC

Cloud platforms

CI/CD

Git

Tools

OpenAI

Anthropic LLMs

Apple Pay

Google Pay

AWS

GCP

Vercel

Railway

Job description

Praxis, Inc. is seeking a technical co-founder to own the full stack for Known, a consumer AI dating product built from the ground up with a focus on delightful UI, robust data flows, and seamless integrations.

You will partner with AI/ML, product, and design teams to translate ambitious ideas into production code, shaping millions of user experiences and leading critical architectural decisions.