Aleksander Kolasinski

Software Engineer. Always learning.

I build software across the full stack. I've shipped production APIs, data pipelines, and client-facing sites for early-stage startups. I also freelance on the side.

Open to full-time software engineering roles.

Work Experience

Software Engineer, FreelanceLa Brea Law, APC

June 2026 – Present

Translated 29 pages of Figma designs into a production Next.js application using React, JavaScript, and Tailwind CSS.
Architected a reusable component system across 24 practice area pages and built server-side form handling via Next.js API routes with schema validation (Zod) and spam protection.
Improved Lighthouse performance score from 65 to 96; configured SEO metadata, Open Graph tags, canonical URLs, XML sitemap, and deployed to Vercel with production security headers.

Next.jsReactTailwind CSSZodVercel

Full Stack Software Engineering InternAtrium Energy

Feb 2026 – Apr 2026

Developed and debugged production REST API endpoints using FastAPI and Python, integrating MongoDB to automate customer onboarding workflows, tested in Docker environments and deployed on AWS EC2.
Implemented JWT/JWKS verification to authenticate CRM requests across a microservice architecture.
Designed a query layer connecting MongoDB property metadata to TimescaleDB, serving time-series property analytics to a React frontend with configurable filtering and date range queries.
Engineered a Python ETL pipeline to ingest and parse hotel reservation data, applying business logic to generate daily outputs structured for Apache Airflow DAGs, following Agile development practices.

FastAPIPythonMongoDBTimescaleDBReactAWS EC2DockerJWTAirflow

Frontend Developer InternFamous Title, LLC

Nov 2023 – Jun 2024

Built a client-facing website for a medical practice using HTML, CSS, and JavaScript, gathering requirements directly from the client and automating patient inquiry routing to reduce manual intake handling.

HTMLCSSJavaScript

Projects

Habit Tracking Web App

Shipped a full-stack habit tracking app with Node.js, Express, and PostgreSQL, including a RESTful API, CRUD operations, and a relational schema.
Built a responsive frontend with HTML, CSS, and asynchronous data fetching.

Node.jsExpress.jsPostgreSQLHTMLCSS

BiteBook Food Journal

Led a team of five to build a cross-platform food journal in Flutter with photo uploads, notes, and daily tracking.
Implemented Firebase Authentication and Storage for secure image handling and real-time sync.
Added sharing via dynamic links and QR codes, allowing users to duplicate entries into their own journals.

FlutterFirebase

Smoking Image Classification

Built a deep learning pipeline using custom CNNs and MobileNetV2 transfer learning to detect smoking behavior.
Improved performance through data augmentation, regularization, and ensemble modeling.
Achieved a test accuracy of 88% with high recall through ensemble modeling and performance optimization using precision-recall metrics and ROC analysis.

PythonTensorFlowMobileNetV2scikit-learnNumPypandas