Mark Erikson Email & Phone Number

San Francisco, Ca, Us

Built the Replay DevTools time-traveling debugger UI and developed new features across the stack:- Modernized Replay's front-end codebase, migrating from 140K LOC of plain JS and legacy React and Redux (from the original Firefox DevTools source), to 100K LOC of modernized Redux Toolkit, React, and TypeScript- Implemented Replay's support for React and Redux DevTools inspection, using our time-travel backend API to extract React component tree data and Redux actions from recorded React applications- Implemented "Jump to Code", which lets users time-travel-debug React apps by jumping to the React props that handled events- Revamped the official React package build pipeline to generate sourcemaps for React production build artifacts- Prototyped runtime perf analysis of React renders and Redux dispatches using our time-travel API- Implemented backend recording processing logic to extract and cache recording paint data in S3- Built a full-stack prototype of "Root Cause Analysis" to diff failing tests, including Postgres tables, GraphQL layer, and UI

Falls Church, Va, Us

The majority of my Northrop career has been spent working on a series of applications that provide terrain line-of-sight calculations for defense purposes.In 2009, I joined a small urgent effort to build a plugin for the FalconView mission planning application that would calculate and display LOS based on current planning elements. After the other two developers moved to other projects, I spent several months adding additional features, as well as optimizing and enhancing the LOS algorithm.In 2011, the LOS algorithm author and I started work on Kontour, a full-blown LOS calculation application. I chose to build it using Play 1.x, GWT, and Google Earth. After my coworker moved on to another project, I continued as the sole developer of Kontour for the next two years, with continued design input from my coworker. In the process, we gradually split the original monolithic web application into a series of standalone web services, primarily written in Python.In 2013, I rejoined my coworker as part of a larger team rewriting an existing web application from scratch. Using our lessons from Kontour's development, we built a service-oriented system that supplies JSON APIs to the smart browser client, which displays information using the Cesium 3D globe toolkit. After a frantic initial development period, our lack of a coherent client-side architecture showed we had collective inexperience with web client development. In response, I led an effort to research JS MVC frameworks. Prototyping showed that Backbone fit our use case, and I spent the second half of 2013 doing most of the work refactoring our codebase for improved architecture and maintainability. In 2014, I designed and implemented a major upgrade to the LOS calculation algorithm that both applications used, enhancing it to allow full 3D antenna-pattern-based RF+LOS calculations.

This was a non-technical job, but a fascinating part of my career. I had the opportunity upon graduation to join an English teaching program in China. I spent four years as part of a team of American teachers, and taught topic classes in English to 10th and 11th-graders at the top high school in Beijing, China.The experience was life-changing, and I'm still good friends with both my fellow teachers and a number of my students. (And in case you're wondering: yeah, four years there, but "wo hui shuo yidian zhongwen".)I did do a fair amount of programming in my spare time, working on several personal side projects.

Broomfield, Co, Us

I worked on a J2EE enterprise workflow application called Knowledge Kinetics (K2), adding a few small features and helping with prototyping and demonstrations.