Hello, I'm a developer.
human being named TJ.

Nice to meet you.

At a glance


I am a Software Engineer at Twosense where I work on the platform and backend teams, working with everything from low-level Windows driver APIs to modern web apps.

I previously worked at MakerBot where I made projects that integrated their extensive line of 3D printers with web-based products to better serve their education and professional customers.

Not only do I work on projects at Twosense, but I have many personal projects listed below (and on GitHub). So check them out as well :)

ExpressPoll 5000 Hacking: I did some security research regarding the ExpressPoll 5000 done at DEF CON 25. It received some press coverage as well:


In my free time, I like poking websites for security vulnerabilities. And, of course, I disclose them responsibly. Here's what I've found. This list may not be up-to-date, because, you know, responsible disclosure and all.

Environment Variable Leak on npm: Found a vulnerability in the npm internal API that leaked environment variables, including API keys and database passwords (Seriously, their Redis password used to be this-is-a-password-for-redis-and-it-is-a-secret-so-dont-share-it), on certain requests.

Cross-Site-Scripting on GoToMeeting: Angular statements put into meeting chat were not properly escaped, and executed on all clients whether they had the chat open or not. This allowed an attacker to execute arbitrary JavaScript on all clients in the meeting.

Cross-Site-Scripting on Transifex: HTML not escaped properly in Glossary and Updates views from the Translate page, allowing an attacker to execute arbitrary JavaScript on a client viewing a certain translation.

Cross-Site Scripting and Privilege Escalation on Big History Project: When updating a user's profile, one could send arbitrary data to the server in the name fields, and that is later shown on the website but isn't escaped, so you could put anything you want in there. It is also shown and effective in the teacher's dashboard, so a student could technically just XSS a teacher.

A certain exploit allows a student to gain access to the teacher dashboard, and do everything a teacher can do (enable tests/quizzes, view student scores, add/delete/edit students and classes, etc.) This is obviously really bad.

Cross-Site-Scripting on Lenovo Unified Workspace: An exploit in how wallpapers on Unified Workspace works allows a user to input arbitrary JavaScript, which is later not escaped properly when loading the workspace dashboard, and is then evaluated in a script.

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