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Hi, I am John

John Derr

Associate Software Engineer at Capital One

Recent computer science graduate from University of Wisconsin-Madison joining Capital One’s Technology Development Program. Passionate about building scalable systems and creating intuitive user experiences.

Skills

Spring Boot
Spring Boot

Extensive experience developing production-grade microservices with Spring Boot, including Spring Security, Spring Data JPA, and Spring Cloud. Implemented REST APIs, authentication systems, and integration with various databases.
Java
Java

Strong object-oriented programming skills with Java 11+. Experience with multithreading, collections framework, streams API, and performance optimization. Developed enterprise applications following SOLID principles.
Cloud Platforms
Cloud Platforms

Hands-on experience with AWS (EC2, S3, Lambda, RDS) and GCP (Compute Engine, Cloud Storage). Deployed scalable applications using cloud-native services and implemented CI/CD pipelines.
Docker & Containerization
Docker & Containerization

Expertise in containerizing applications using Docker, including multi-stage builds and optimization techniques. Experience with Docker Compose for local development environments and container orchestration basics.
Linux System Administration
Linux System Administration

Proficient in Linux environments (Ubuntu, CentOS). Skilled in bash scripting, process management, and system configuration. Experience with server maintenance and troubleshooting.
Version Control (Git)
Version Control (Git)

Extensive Git experience in collaborative environments. Familiar with Git workflows (Git Flow, GitHub Flow), rebasing, cherry-picking, and managing large codebases. Regular user of GitHub and GitLab.
C/C++
C/C++

Solid understanding of memory management, pointers, and low-level programming. Developed system-level software including a custom database management system and OS components as academic projects.
REST API Design
REST API Design

Designed and implemented RESTful APIs following best practices. Experience with OpenAPI/Swagger documentation, versioning strategies, and authentication (JWT, OAuth2).
SQL & Databases
SQL & Databases

Strong database skills including schema design, query optimization, and transactions. Experience with PostgreSQL, OracleDB, and basic knowledge of NoSQL solutions.

Experiences

1
Capital One

Aug 2025 - Present

Dallas, TX

Capital One Financial Corporation is an American bank holding company specializing in credit cards, auto loans, banking, and savings accounts.

Associate Software Engineer (Technology Development Program)

Aug 2025 - Present

Responsibilities:
  • Full Stack development using Spring Boot and Angular
  • Cloud-native development using ECS on AWS
  • Agile methodologies and DevOps practices
UW-Madison, College of Engineering

Feb 2022 - May 2025

Madison, WI

University of Wisconsin, College of Engineering is a public research university in Madison, Wisconsin, United States.

Integration Engineering Intern

May 2024 - May 2025

Responsibilities:
  • Developed 2 REST APIs using Spring Boot Framework, replacing outdated SOAP APIs to modernize system architecture and ease of use
  • Migrated SQL queries from an old database schema to JPA-based queries on a new schema, while maintaining accurate data retrieva
  • Authored the OpenAPI specification, independently defining and documenting endpoints for project use.
Help Desk Consultant

Feb 2022 - May 2025

Responsibilities:
  • Provided comprehensive technical support for CAE, troubleshooting hardware, software, and network issues, ensuring swift resolution and excellent customer service.
  • Monitored systems and communicated with users and staff, resolving issues efficiently, including handling critical incidents like a total power outage.
2
3
Bethel Lutheran Church

May 2023 - December 2024

Madison, WI

Bethel Lutheran Church is a large church in Madison, WI.

Assistant Sound Engineer

May 2023 - December 2024

Responsibilities:
  • Setup and operate audio equipment for the band during weekly church services, ensuring high-quality sound for congregants, broadcast to WKOW 27, and YouTube.

Education
University of Wisconsin - Madison
2021-2025
B.S. in Computer Science & Data Science
GPA: 3.53 out of 4
Taken Courses:
Course Name Obtained Credit
Algorithms A
Artificial Intelligentice AB
Computer Networks AB
Database Management Systems A
Operating System A
Optimization AB
Data Structures and Algorithm AB
Extracurricular Activities:
  • Associate Director of Online Spaces for Wisconsin Union Directorate Games Committee
  • Vicepresident of Remote Trips for Hoofers Scuba Club
  • Observing Station Leader for University of Wisconsin - Madison Astronomy Club

Projects

Leela Chess Zero
Leela Chess Zero
Developer June 2025 - Present

An open-source chess engine that uses neural networks and reinforcement learning to play chess at a high level.

hobby chess ai
Star
Games Database
Games Database
Owner Dec 2024 - June 2025

A simple way to vizualize the games that Wisconsin Union Directorate Games Committee owns. It is written with React-js and Spring Boot.

professional hobby cloud
Star
CAE-ManageIP-Rest
Developer June 2024 - Mayhu 2025

An IP and Asset Management solution for UW-Madison College of Engineering. It is REST API written with Spring Boot for managing DNS/DHCP/Devices/etc.

professional cloud
CAE-Account Management-Rest
Developer June 2024 - May 2025

An account management solution for end user and admistrative access to accounts for UW-Madison College of Engineering. It is REST API written with Spring Boot for managing permissions/groups/etc.

professional cloud
Set Traveling Sales Person Solver
Owner Sept 2023 - Dec 2023

An efficient Set Traveling Sales Person solver using Python and GAMS to optimize flight paths for a private jet traversing all 48 contiguous U.S. states. The initial implementation analyzed 200 airports, delivering a solution in just 14 hours.

academic TSP
Details

Recent Posts

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LLM Hardware Chronicles: The Unexpected Journey from NVIDIA to AMD and Back

After months of experimenting with local Large Language Models (LLMs) via Ollama, I’ve learned one fundamental truth: You can never have enough VRAM. This journey from consumer GPUs to datacenter cards has been filled with interesting discoveries about the balance between hardware capabilities, software ecosystems, and practical limitations. The Initial Setup My journey with the Derr AI system began with the wild west of models, experimenting with everything I could get my hands on to understand what would run locally. After much tinkering, I settled on running Mistral Small (22B parameters) on an NVIDIA RTX 3060 with 12GB of VRAM. While the 3060 is a solid card for many tasks, it quickly hit its limits when running larger language models.

Wednesday, January 1, 2025 | 5 minutes Read
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Welcome

Hello There!

Saturday, March 16, 2024 | 1 minute Read