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AI Software Engineer · Quant Developer

Ruben Lekli

For over half a decade, building, managing, and maintaining production software, from AI-powered applications and workflow infrastructure to data pipelines and quant-dev tools.

rubenlekli.com

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About

Turning complex requirements into production systems.

Turning non-technical client requirements, messy product ideas, and real engineering constraints into production systems. Scope and priority decisions happen early, and stay firm under pressure: what ships first, what gets cut, and what risks breaking if the timeline shrinks. Most projects get built with clients, founders, or team leads who need AI-powered applications, workflow infrastructure, data pipelines, internal tools, new products, or optimizations to existing systems.

Quant dev is part of the same engineering work, with more finance, mathematics, statistics, and optimization in the loop. In practice, that's building research, backtesting, portfolio, and robustness tooling to test market ideas properly, for client work and for strategies traded independently.

AI tools are part of how the work gets done; mostly used for speed and to sketch out scaffolding. Output correctness remains under careful review, ensured by the test harness, the criteria, and a strong oracle, to spot any errors that may slip through. The work still has to be structured clearly, reviewed properly, and maintained like any other production system.

2021

Building software since

83.6%

Typical speed-up measured on client workflows

10+

Production systems shipped

7

Languages shipped to production

Projects

Most production work lives in private repos. Here is what you can inspect.

Need something like this built for your business? I take on client work through FlowSolutions tell us about your project.

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Private build

Quantitative Investing System

Designer & Developer

My private research and execution stack for digital-asset strategies. It starts with alpha ideas, runs them through a custom Python backtester, walk-forward validation, portfolio construction, and bias checks, then tracks what is strong enough to trade live.

PythonSystematic tradingPortfolio construction

References

What the people I have built for say.

“Technical precision, creativity, and a sharp understanding of both blockchain data structures and financial principles.”

“A genuine passion for applying data-driven insights to complex financial and blockchain systems, intellectual curiosity, and disciplined work ethic.”

PV

Polina Vertex

Co-founder, Syntagma Labs · reference letter, 2026