AI Harness Engineer (100% Remote, Worldwide)

Tether.io; Denmark; Remote; DKK 900,000 - 1,400,000; Full time

Job summary

Tether.io in Denmark is seeking an experienced AI Harness Engineer to design and implement integrations for AI, enabling local AI to scale via P2P technology and to connect people to AI services.

You will push QVAC to new levels, develop modular, maintainable code, and collaborate in a remote, globally distributed team while delivering reliable features across model types.

Qualifications

• 5+ years building production software, with P2P systems, AI/LLM tooling, or both.
• Hands-on experience building agent harnesses, including tool calling, agent loops, context management, and structured outputs.
• Experience building evals and test infrastructure for non-deterministic systems.
• Strong JavaScript/TypeScript, with experience modelling complex state, from sync protocols to agent loops.
• Open-source contributions to P2P, networking, or AI tooling projects.
• Experience designing for failure, including network partitions, model errors, timeouts, and retries.

Responsibilities

• Deliver new features and bug fixes with a focus on reliability, performance, and user satisfaction
• Design and develop new tools and modules, enabling new AI capabilities while ensuring success of a wide variety of model types and sizes
• Maintain high codebase quality through consistent coding standards, code reviews, and automated testing
• Implement and develop P2P technology for use with local AI
• Strong competency in writing modular, maintainable code.
• Experience creating and managing reusable npm modules.
• Solid skillset in testing & debugging.
• Strong understanding and comfort with developing and using AI tools.
• Deep interest or experience with P2P technologies or distributed systems.
• Comfort working in a remote, globally distributed team; good communication skills.
• Hacker who never stops experimenting.

Skills

JavaScript/TypeScript

Open-source

P2P systems

AI tooling

Agent harnesses

Tools

npm modules

Job description

Join Tether and Shape the Future of Digital Finance

At Tether, we’re not just building products, we’re pioneering a global financial revolution. Our cutting-edge solutions empower businesses—from exchanges and wallets to payment processors and ATMs—to seamlessly integrate reserve-backed tokens across blockchains. By harnessing the power of blockchain technology, Tether enables you to store, send, and receive digital tokens instantly, securely, and globally, all at a fraction of the cost. Transparency is the bedrock of everything we do, ensuring trust in every transaction.

Innovate with Tether

Tether Finance: Our innovative product suite features the world’s most trusted stablecoin, USDT, relied upon by hundreds of millions worldwide, alongside pioneering digital asset tokenization services.

Tether Power: Driving sustainable growth, our energy solutions optimize excess power for Bitcoin mining using eco-friendly practices in state-of-the-art, geo-diverse facilities.

Tether Data: Fueling breakthroughs in AI and peer-to-peer technology, we reduce infrastructure costs and enhance global communications with cutting-edge solutions like KEET, our flagship app that redefines secure and private data sharing.

Tether Education: Democratizing access to top-tier digital learning, we empower individuals to thrive in the digital and gig economies, driving global growth and opportunity.

Tether Evolution: At the intersection of technology and human potential, we are pushing the boundaries of what is possible, crafting a future where innovation and human capabilities merge in powerful, unprecedented ways.

Why Join Us?

As an AI Harness Engineer, you’re not just building integrations for AI —you’re developing new and innovative ways to connect people to local AI, and how that AI will become a fixture in our lives. You will push QVAC to new levels, using P2P technology to enable limitless scale, making you essential to the company’s success in the competitive local AI assistant market.

• Deliver new features and bug fixes with a focus on reliability, performance, and user satisfaction
• Design and develop new tools and modules, enabling new AI capabilities while ensuring success of a wide variety of model types and sizes
• Maintain high codebase quality through consistent coding standards, code reviews, and automated testing
• Implement and develop P2P technology for use with local AI
• Strong competency in writing modular, maintainable code.
• Experience creating and managing reusable npm modules.
• Solid skillset in testing & debugging.
• Strong understanding and comfort with developing and using AI tools.
• Deep interest or experience with P2P technologies or distributed systems.
• Comfort working in a remote, globally distributed team; good communication skills.
• Hacker who never stops experimenting.

Qualifications

• 5+ years building production software, with deep experience in P2P systems, AI/LLM tooling, or both
• Hands-on experience building agent harnesses, including tool calling, agent loops, context management, and structured outputs
• Experience building evals and test infrastructure for non-deterministic systems
• Strong JavaScript/TypeScript, with experience modelling complex state, from sync protocols to agent loops
• Open-source contributions to P2P, networking, or AI tooling projects
• Experience designing for failure, including network partitions, model errors, timeouts, and retries