AI application studio

We build AI applications.

From concept to production. Machine learning, natural language processing, and intelligent systems that solve real problems.

Built for production,
not demos.

CitronLab is a technology studio founded by Leo Gestetner and Nick Brandt, with over 30 years of combined experience building scalable solutions. A Thankz, LLC company — available globally.

We specialize in AI/ML applications, from large language models and RAG systems to temporal memory architectures and on-device inference. Our approach is production-first — we build systems that work at scale, not just demos.

Leo Gestetner, CEO

Leo Gestetner

CEO & Co-founder

Entrepreneur and athlete with decades of experience leading global remote teams. Leo believes the best work comes from a balanced foundation of family, health, and meaningful work.

Nick Brandt, CTO

Nick Brandt

CTO & Co-founder

Technology leader specializing in AI, machine learning, and systems that understand context. Built everything from RAG systems to temporal memory architectures.

0+
Years building AI products together

From enterprise networking to personal memory architectures.

0+
Years combined experience

From early web to AI-native systems at scale.

0
Core research areas

Applied AI research across LLMs, memory systems, and serverless architectures.

Full-stack AI,
end to end.

Large Language Models

Custom LLM integration, prompt engineering, fine-tuning pipelines, and RAG-augmented inference for your domain.

RAG Systems

Retrieval-augmented generation for domain-specific knowledge bases. Vector search, semantic chunking, and hybrid retrieval.

Temporal Memory

AI systems that understand time, context, and relevance decay. Memory architectures that surface what matters now.

On-Device AI

Private, fast inference without cloud dependency. MLX and Core ML implementations that run entirely on-device.

Cloud Infrastructure

AWS serverless architectures that scale to zero and back. Lambda, DynamoDB, API Gateway — optimised for cost and latency.

Full-Stack Development

Python, Rust, TypeScript, React, React Native, Swift. From backend inference APIs to polished mobile and web experiences.

Selected Work

Zenvoy

Fortune 500 clients across 3 continents

Enterprise AI networking platform that helped organizations connect their people. Built intelligent systems that understood who should know each other — and why. Served Fortune 500 clients across events, hospitality, and corporate sectors.

Python · React · PostgreSQL · AWS · Machine Learning

13 years Enterprise
Livio

AI coaching for thousands of users on iOS + Android

AI health coaching platform. An AI assistant named Kai helps users build sustainable health habits through natural conversation — tracking nutrition, sleep, exercise, hydration, and mindfulness in one place.

React Native · Node.js · AWS · Conversational AI

iOS + Android AI Health Coach Conversational UX
CitronVerified

CitronVerified

10,000+ documents per batch, automated forensic analysis

Internal corporate document verification platform. Automates fraud detection across invoices, contracts, and expense reports using AI-driven analysis. Processes batches of 10,000+ documents with multi-tier forensic analysis.

Python · Rust · React · AWS CDK · Amazon Bedrock · PostgreSQL

Internal Tool Document AI Fraud Detection

Let's build something.

Have a project in mind? Looking to add AI capabilities to an existing product? We'd love to hear about it.

Email us at team@citronlab.com or use the form.