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Full Stack AI Engineer

Kaizen Soft Solutions, LLCNew York, NY🇺🇸United StatesPosted 7 Aug 2026

Why This Role Stands Out

This role offers an exciting opportunity to build AI-native products from the ground up within a dynamic early-stage startup, providing significant impact and ownership. You'll thrive here if you have extensive full-stack experience and a proven track record of developing AI-powered products, allowing you to shape the company's technical future. Apply now to leverage your expertise in a groundbreaking AI venture.

Quick Overview

Work Type
On Site
Level
Mid Senior

Job Description

Position: Full Stack AI Engineer
Location: San Francisco, CA & New York City, NY - Onsite
Duration: Full Time
Experience: 8+ years

Candidate Requirement:

  • Candidate must have prior experience working at an early-stage startup.

  • Candidate should have strong full-stack experience across frontend, backend, databases, APIs, cloud infrastructure, and production deployments.

  • Candidate must have practical experience building AI-powered products. API experimentation, personal projects, coursework, or basic chatbot integrations alone will not qualify.

  • Strong candidates will have experience with AI agents, LLM integrations, RAG, model tool calling, multimodal AI, voice AI, evaluations, or real-time AI systems.

About the Role:

Our client is looking for a highly hands-on engineer who can help build and launch AI-native products from the ground up. You will work closely with the founders to turn ideas into production-ready applications and help shape the company’s technical foundation.

The right candidate is comfortable working across frontend, backend, infrastructure, and AI systems. You should enjoy fast-moving startup environments, changing requirements, rapid iteration, and taking complete ownership of what you build.

Responsibilities:

  • Build, test, launch, and improve full-stack products from zero to one

  • Develop modern frontend applications using React, Next.js, or similar technologies

  • Build backend services, APIs, databases, and third-party integrations

  • Create AI-powered features using large language models and multimodal models

  • Build AI agents that can use tools, complete workflows, and interact with external systems

  • Develop retrieval-augmented generation, embeddings, vector search, and knowledge systems

  • Integrate voice AI, speech-to-text, text-to-speech, or real-time conversational systems

  • Implement structured outputs, tool calling, model routing, and human approval workflows

  • Build evaluation, monitoring, and testing systems for AI performance

  • Improve application reliability, scalability, security, latency, and AI inference costs

  • Work directly with founders, users, and product stakeholders

  • Help make product, architecture, and technology decisions

Qualifications:

  • 4 or more years of professional software engineering experience

  • Proven experience building and launching a product from zero to one

  • Prior experience working at an early-stage startup

  • Strong experience across frontend and backend development

  • Strong skills in TypeScript, JavaScript, React, and Next.js

  • Backend experience with Node.js, Python, FastAPI, Go, or similar technologies

  • Experience with PostgreSQL, APIs, cloud infrastructure, and production deployments

  • Hands-on experience integrating large language models into production applications

  • Experience with AI agents, RAG, tool calling, embeddings, multimodal AI, or voice AI

  • Strong product judgment and the ability to operate with limited direction

  • Ability to move quickly while maintaining high engineering standards

  • Must be actively hands-on and writing production code

Preferred Experience:

  • OpenAI, Anthropic, Gemini, or open-source AI models

  • Model Context Protocol and agent orchestration frameworks

  • Lang Graph, Llama Index, Vercel AI SDK, or similar tools

  • Vector databases such as Pinecone, Qdrant, Weaviate, or pgvector

  • Voice AI, WebSocket''s, WebRTC, or real-time streaming systems

  • AI evaluations, observability, prompt injection protection, and model security

  • Docker, AWS, Google Cloud, Azure, or serverless infrastructure

  • Experience as an early, founding, or first engineering hire

 

Know anyone who might be interested?
Kindly let me know if you have any Suitable Candidates available for this opportunity.
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Skills

Docker
FastAPI
Next.js
Node.js
AWS
Azure
Google Cloud
JavaScript
LLM
Python
React
TypeScript
Vercel
WebSocket

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