Founding AI Engineer

Asyn; Greater London; Hybrid; GBP 120,000 - 160,000; Full time

Benefits offered by this job

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Central London office

Job summary

Asyn is building proprietary AI infrastructure for investment firms in London. You’ll be among the first technical hires, shaping the product from day one and building frontier agentic systems in high-stakes finance.

You will design agentic harnesses, create evaluation stacks, post-train and fine-tune open-weight models, and own production-quality code while collaborating with fixed income analysts, traders and portfolio managers.

Qualifications

• Experience building agentic harnesses or applications.
• Prior experience setting up model and/or agent evals and building custom benchmarks.
• Hands-on post-training and/or fine-tuning of open-weight models.
• Solid foundations in classical ML and deep learning.
• Solid fundamentals in statistics, data analytics and data science concepts.
• Strong software engineering fundamentals - you write production-quality code and can own systems end-to-end.
• A fearless, can-do mindset coupled with enough humility to know your limitations and work towards overcoming them.

Responsibilities

• Design and build agentic harnesses for deep-research workflows.
• Build our eval stack: custom benchmarks for financial reasoning tasks, model/agent evaluation pipelines and regression tooling that let us ship confidently.
• Post-train and fine-tune open-weight models on proprietary workflows and data, so each customer's edge compounds inside its own walls.
• Work alongside fixed income analysts, traders and portfolio managers, learning about this fascinating field and co-designing solutions for them.
• Work with financial datasets - bond pricing, issuance calendars, market data, building the analytics and data pipelines the agents depend on.
• Shape engineering culture, tooling and architecture from day one.

Skills

Agentic harnesses

Model evals

Fine-tuning

ML fundamentals

Statistics

Software engineering

Growth mindset

Job description

Asyn is building proprietary AI infrastructure for investment firms that manage the $161tn global bond market. A fixed income firm's coverage, margin and AUM have only ever scaled with headcount. Asyn replaces that constraint with purpose-built agents that reduce the time to decision in the investment process by delivering expert human-grade work. Founded by a fixed income expert with 13 years managing $20bn+ portfolios and a second-time VC-backed technical founder, we are live with a handful of regulated investment managers and growing fast.

The role

You'll be one of our first technical hires, working directly with the founders to build world-class agentic decision infrastructure for fixed income. You'll be in the driver's seat, shaping the product from day 1: the agentic research/decision systems at the core, the evaluation infrastructure that proves they work, and the continual learning loop that makes them compound over time. This is a role for an elite AI engineer who wants depth, breadth, ownership, and a direct mandate to build frontier agentic systems in high-stakes finance.

What you'll do

• Design and build agentic harnesses for deep-research workflows: multi-step analyses over deals, issuers and markets with tool use, memory and orchestration.
• Build our eval stack: custom benchmarks for financial reasoning tasks, model/agent evaluation pipelines and regression tooling that let us ship confidently.
• Post-train and fine-tune open-weight models on proprietary workflows and data, so each customer's edge compounds inside its own walls.
• Work alongside fixed income analysts, traders and portfolio managers, learning about this fascinating field and co-designing solutions for them.
• Work with financial datasets - bond pricing, issuance calendars, market data, building the analytics and data pipelines the agents depend on.
• Shape engineering culture, tooling and architecture from day one.

Some skills that matter

• Experience building agentic harnesses or applications.
• Prior experience setting up model and/or agent evals and building custom benchmarks.
• Hands-on post-training and/or fine-tuning of open-weight models.
• Solid foundations in classical ML and deep learning.
• Solid fundamentals in statistics, data analytics and data science concepts.
• Strong software engineering fundamentals - you write production-quality code and can own systems end-to-end.
• A fearless, can-do mindset coupled with enough humility to know your limitations and work towards overcoming them.

Nice to have

• Domain experience or genuine interest in finance - especially trading, portfolio management or fixed income.
• Original research published at leading AI conferences.
• Former (technical) founders or early engineers in startups will be regarded highly.

What we offer

• A frontier problem: proprietary AI for one of the largest and least-automated markets in the world.
• Direct exposure to customers, investors and technical / product decisions.
• Competitive salary based on expertise and early-stage stock options.
• Office in central London with a bunch of perks.