Fullstack Developer AI Applications

About OpenTrain

OpenTrain AI is the hiring and contracting organization for this role and the #1 platform for finding and building careers in AI training and data labeling. OpenTrain helps people discover AI work, build a credible professional profile, and grow their experience in a rapidly developing industry.

• Work on applications powered by foundation models and modern AI infrastructure.
• Build a portfolio around practical AI projects and software development.
• Create a free OpenTrain account and apply in minutes.

About AI Application Development

AI training and data labeling are the human side of building artificial intelligence, while AI application developers turn model capabilities into useful products. These systems support tasks such as model evaluation, reasoning, and user-facing workflows, making reliable software engineering essential to how AI is built and used.

• Work remotely with modern AI and web technologies.
• Contribute to applications involving large language models and model inference.
• Help make AI capabilities dependable, scalable, and accessible through software.

The Role

OpenTrain is recruiting a Fullstack Developer, AI Applications to build user-facing applications, APIs, and integrations on top of large language model infrastructure. You will turn model inference capabilities into reliable, scalable product features across frontend and backend systems, contributing to AI projects involving foundation models, evaluation, and reasoning.

This is an entry-level, part-time contractor opportunity requiring 20+ hours per week. The role is open worldwide and uses English.

• Role type: Contractor and part time
• Experience level: Entry level
• Time commitment: 20+ hours per week
• Work location: Worldwide and remote
• Working language: English

What You'll Do

You will work across the application stack, connecting modern frontend experiences with backend services, APIs, databases, and LLM inference systems. The work includes both product development and the operational practices needed to support reliable applications.

• Build and ship end-to-end web applications spanning frontend interfaces, backend services, and APIs.
• Integrate LLM inference endpoints using REST, gRPC, streaming responses, server-sent events, and WebSockets.
• Develop scalable backend services with GCP products including Cloud Run, Cloud Functions, Firestore, Cloud SQL, and GCS.
• Create asynchronous workflows using job queues, webhooks, and long-running inference tasks.
• Design and maintain integrations with relational and NoSQL databases and external services.
• Support deployment, monitoring, reliability, and application performance with infrastructure and DevOps teams.

Required Skills

Applicants should be able to contribute to production-oriented fullstack development and integrate model capabilities into working applications. The following skills and experience are required or specifically valued for the role.

• Strong software development experience with Python and Node.js or TypeScript.
• Production experience integrating LLM APIs or model inference endpoints.
• Hands-on frontend application development with React, Next.js, or a comparable modern framework.
• Strong API design knowledge, including REST and one or more of streaming, server-sent events, WebSockets, or gRPC.
• Experience with GCP services, Docker, Git, and CI/CD pipelines is valuable.
• Experience with relational and NoSQL databases is valuable.

Why Work With OpenTrain

AI training and data-labeling work is a fast-growing way to build experience in technology. OpenTrain gives contributors a place to develop a professional profile, discover opportunities that match their skills, and turn project work into a lasting AI career portfolio.

• Work remotely from anywhere with a computer and internet connection.
• Choose a flexible part-time schedule that fits your availability.
• Build experience at the intersection of software engineering and generative AI.
• Showcase credible project experience through your OpenTrain profile.

How to Apply

Create a free account on OpenTrain, complete your profile, and apply for this Fullstack Developer, AI Applications contract role. Highlight your Python, Node.js or TypeScript, frontend, API, LLM integration, cloud, and database experience so your application reflects the skills most relevant to the work.

• Review the role requirements.
• Create or update your OpenTrain profile.
• Apply through OpenTrain in minutes.