Back End Developer

Company Description

Hello Recruiter is an AI-powered recruiting platform that conducts autonomous conversational interviews using intelligent digital avatars. Our AI agents conduct in-depth interviews across chat, voice, and video—giving every candidate a fair, consistent experience while saving recruiters hours of screening time. We're an early-stage startup building at the intersection of AI and recruiting.

Role Description

We're looking for a Backend Engineer to build and scale the systems that power our AI interview platform. You'll work on everything from our core API and data layer to AI orchestration, real-time communication infrastructure, and third-party integrations. This is a high-ownership role where your decisions will directly shape our architecture as we grow.

If you're excited about building systems that coordinate multiple AI models, handle real-time audio/video, and process thousands of interviews—this is the role.

What You Will Do

• Design, build, and maintain APIs and backend services
• Build and optimize our AI orchestration layer (routing between Claude, GPT-4, Gemini based on use case)
• Develop integrations with voice AI systems (speech-to-text, text-to-speech)
• Work on real-time infrastructure for live interviews (WebSockets, event-driven systems)
• Build and maintain our ATS backend (job pipelines, candidate workflows, automation rules)
• Design database schemas and optimize queries for performance
• Implement background job processing for async tasks (resume parsing, interview analysis, notifications)
• Build integrations with third-party ATS platforms (Greenhouse, Lever, Ashby)
• Write secure, tested, and well-documented code
• Participate in architecture discussions and code reviews
• Set up monitoring, logging, and alerting for production systems

What We Are Looking For

Must Have:

• 2+ years of professional backend development experience
• Strong proficiency in backend technologies like dotnet, java or ruby on rails
• Experience designing and building RESTful APIs
• Solid understanding of relational databases (MS SQL or PostgreSQL preferred)
• Understanding of authentication and authorization (JWT, OAuth)
• Familiarity with cloud infrastructure (AWS, GCP, or Azure)
• Experience with Git and collaborative development workflows
• Ability to debug production issues and think systematically
• Good communication skills in English
• Self-motivated and comfortable working independently in a remote environment

Good to Have:

• Experience integrating with LLM APIs (OpenAI, Anthropic, Google)
• Familiarity with real-time systems (WebSockets, WebRTC, event-driven architecture)
• Knowledge of message queues (RabbitMQ, Kafka, SQS)
• Understanding of CI/CD pipelines
• Previous startup experience or comfort with fast-moving environments
• Interest in AI/ML and how LLMs work

Tech Stack

• Languages:

  Python, dotnet

• Database:

  MS SQL, PostgreSQL, Redis, Azure Storage

• AI:

  Gemini, Open Router, Anthropic Claude, Cartesia, LiveKit, Vapi, Langfuse

• Infrastructure:

  Azure

• Version Control:

  Git, GitHub

What We Offer

• Ownership and impact from day one—small team, big responsibility
• Work on a product at the cutting edge of AI and recruiting
• Flexible remote work with async-friendly culture
• Direct collaboration with founders and senior engineers
• Room to grow as the company scales

What We Expect

• You ship. We value working software over endless discussions.
• You take ownership. If something's broken in your area, you fix it without being asked.
• You communicate proactively. Remote work requires over-communication, not silence.
• You're pragmatic. Perfect is the enemy of done—but you know when quality matters.
• You're curious. Our product touches AI, voice, video, and real-time systems. You don't need to be an expert in all of them, but you should want to learn.