Open to opportunities

Lucas A

@lucasa

Message

Senior full-stack engineer building cloud-native AI SaaS with React, FastAPI, and AWS.

United States

Message

What I'm looking for

I’m looking for a team building secure, scalable cloud-native SaaS with modern engineering practices and real AI integrations. I want to architect distributed systems, own performance improvements, and ship reliable features through strong CI/CD.

I’ve built and scaled modern SaaS platforms for over 7 years, delivering secure, high-quality software across healthcare, fintech, and AI-driven products. I’m especially drawn to modern engineering practices that improve performance, scalability, reliability, and developer productivity.

Most recently as a Senior Full Stack Engineer at CognitiveScale, I architected AI-powered SaaS applications using React, TypeScript, FastAPI, PostgreSQL, and AWS, supporting 10K+ daily active users across enterprise environments. I designed scalable backend services for LLM integrations, RAG pipelines, and vector search—turning complex data retrieval into intelligent AI-driven workflows.

I also modernized a legacy monolithic platform into Docker-based microservices on AWS ECS, reducing deployment time by 50% and improving release consistency. By optimizing performance with Redis caching, asynchronous processing, and database tuning, I reduced average API response time by 35%, while collaborating to maintain 99.9% production availability and strong CI/CD reliability.

Experience

Work history, roles, and key accomplishments

Current

Senior Full Stack Engineer

Current

CognitiveScale

Oct 2023 - Present (2 years 9 months)

Architected AI-powered SaaS applications and scalable backend services for LLM integrations, RAG pipelines, and vector search supporting 10K+ daily active users. Modernized a legacy monolith into Docker-based microservices on AWS ECS, improved performance, and maintained 99.9% production availability.

React TypeScript fastAPI PostgreSQL AWS ECS AWS Lambda AWS S3 Docker Microservices Redis GitHub Actions Jenkins CI CD LLM Integrations Vector Search Caching

Full Stack Python Developer

Softeq

Jul 2021 - Sep 2023 (2 years 2 months)

Developed enterprise SaaS applications using React, Django, Flask, Python, and PostgreSQL for high-volume business workflows. Built RESTful APIs and ETL pipelines, optimized PostgreSQL performance to reduce API latency by 30%, and implemented authentication/authorization and third-party integrations.

React JavaScript Python Django Flask PostgreSQL REST APIs ETL Docker JWT OAuth 2.0 Authentication Authorization Third Party Integrations API Integration Agile Development

Software Engineer

Frogslayer

Feb 2019 - Jun 2021 (2 years 4 months)

Developed enterprise web applications using React, Flask, PostgreSQL, and RESTful APIs for multiple client projects. Built reusable UI components to improve feature development speed by 20%, integrated third-party APIs, and resolved production issues to improve performance and reliability.