Principal Software Engineer
Jon Lee
I build software at scale — manufacturing systems for spacecraft, payment platforms moving billions of transactions, and execution and planning tools driving billions in retail revenue. Based in Minneapolis, MN, with 15+ years across aerospace, e-commerce, retail, and defense.
Career
Where I've built things
Blue Origin
04/2022 – PresentPrincipal Software Engineer
- Hands-on technical leader for multi-team architecture across Manufacturing Part Assembly, Pedigree, and Quality Management — supporting New Shepard, New Glenn, Engines, Lunar, and Advanced Programs.
- Led a cross-functional team to build a full-stack Event Reporting System in two months, enabling a NASA Lunar vehicle contract bid.
- Drove a 100-engineer org to adopt Infrastructure as Code with Terraform across 40+ micro-services spanning 7+ teams.
- Built an internal AI browser extension bringing ChatGPT capabilities to engineers.
Target
02/2021 – 04/2022Principal Software Engineer
- Technical leader of a 30-person engineering team defining architecture and culture for Merchandising Assortment and Financial Planning across all 1,900 nationwide stores.
- Built planning products enabling data-driven decisions across historical, analytical, and operational datasets, contributing to billions in revenue.
- Exposed elasticity and demand forecasting Data Science models to the enterprise through scalable APIs consumed by Price, Promo, and Supply Chain.
Amazon
10/2019 – 06/2020Software Development Engineer
- Designed and developed the next-generation payment processing platform handling worldwide traffic for millions of customers.
- Migrated over 2 billion credit cards to AWS with PCI compliance and zero downtime.
Blue Origin
06/2020 – 02/2021Senior Software Engineer
- Developed manufacturing systems for the assembly of New Shepard and New Glenn space vehicles.
- Managed tracking and resolution of thousands of nonconforming components.
- Built capabilities for receiving and inspecting parts from vendors.
Target
03/2015 – 10/2019Lead Software Engineer
- Designed and developed a pricing application analyzing millions of competitor prices, driving numerous price adjustments.
- Built enterprise applications for authoring, managing, and publishing promotions.
- Architected shipping and handling rate management for Target.com.
- Delivered full-stack solutions using AngularJS, RESTful micro-services, and Neo4j.
Lockheed Martin
05/2008 – 03/2015Software Engineer → Senior R&D Engineer
- Developed R&D air traffic control prototype software for the En Route Automation Modernization (ERAM) program used in future FAA and international contracts.
- Built Java Swing applications, messaging services, thread management utilities, and flight simulations.
- Graduate of the Lockheed Martin Engineering Leadership Development Program.
Toolkit
How I build
Languages
- Java
- Python
- TypeScript
- JavaScript
- C/C++
- Rust
Cloud & Infra
- AWS (Lambda, EC2, DynamoDB, MSK, API GW)
- Kubernetes / EKS
- Terraform / CDK
- Docker
- Kafka
- GitLab CI/CD
Frameworks & DBs
- Spring Boot
- React
- GraphQL
- Node.js
- PostgreSQL
- MongoDB / DocumentDB
- Neo4j
Practices
- Domain-Driven Design
- DevSecOps
- CI/CD
- RESTful APIs
- Agile / Kanban
- Observability
Philosophy
How I think about engineering
The best software I've worked on wasn't defined by its technology choices. It was defined by the clarity of thinking behind it — clear problem statements, honest trade-offs, and teams that could reason about failure before failure happened.
From space vehicle manufacturing at Blue Origin to migrating 2 billion credit cards at Amazon to demand-forecasting platforms driving revenue decisions at Target — the common thread is engineering that is customer obsessed and built to last.
I believe the highest-leverage thing a Principal Engineer does isn't write code — it's create organizational clarity: clear direction, observable systems, and teams capable of executing independently at scale.
Thoughts
Recent writing
What No One Tells You About Becoming a Principal Engineer
The title is a milestone, but the real shift happens long before the promotion. A reflection on what the role actually demands — and why most engineers misunderstand it.
Setting the Standard: Why I Still Do the Small Stuff as a Principal Engineer
Gaining trust and setting a high standard isn't a top-down mandate. It's about setting a precedent through action — and learning that no task is beneath you.
Client and Server Side Encryption with Crypto and CryptoJS
A practical guide to symmetric, asymmetric, and hybrid encryption in JavaScript — covering CryptoJS on the client and Node's built-in crypto module on the server.
Connect
Let's build something that matters.
Whether you're thinking about architecture, engineering leadership, or just want to exchange ideas — I'm always glad to talk.