I'm a PhD Candidate in Computer Science in the Security Group at Princeton University, which has some history in this area. I sit in the Center for Information Technology Policy where I study security, privacy, and how technology informs policy decisions. I'm currently advised by Ed Felten and Andrew Appel.

The following facts about me may or may not interest you: I'm a National Science Foundation Graduate Research Fellow. For many years, I traveled to Boston each fall to perform Improbable feats of engineering. I got married recently.

In the past, I attended a small college near Boston, MA where I spent a lot of time playing with technology and making it accessible to the masses. Prior to that, I grew up in Monterey, CA where I can recommend a good dentist. It was there that I got my start as a Computer Scientist, and experienced the inner workings of government.

I don't always blog, but when I do, I do it on Freedom to Tinker. I can be found on Twitter as @realjoshkroll.


I'm interested in a broad swath of topics in and outside of security (computer and otherwise), privacy (online and otherwise), and related questions in public policy. My current research is on Accountable Algorithms.

For more information, you should contact me.


  • Bonneau, J., Narayanan, A., Miller, A., Clark, J., and Kroll, J. "Mixcoin: Anonymity for Bitcoin with accountable mixes," Financial Cryptography, 2014 [PDF].
  • Kroll, J., Davey, I., and Felten, E., "The Economics of Bitcoin Mining, or Bitcoin in the Presence of Adversaries", The Twelfth Workshop on the Economics of Information Security (WEIS 2013), Washington, DC, June 10-11 2013. [PDF]
  • Kroll, J. and D. Dean, “BakerSFIeld: Bringing Software Fault Isolation to the x64,” SRI Computer Science Laboratory Technical Report, 2009.
  • Martell, C. and J. Kroll, “Corpus-Based Gesture Analysis: An extension of the FORM dataset for the automatic detection of phases in a gesture”, Int. J. Semantic Computing, 1(4): 521-536 (2007).
  • Martell, C. and J. Kroll, “Using FORM to Predict Phase Labels”, Proceedings of the Language Resources and Evaluation Conference, Workshop on Multimodal Corpora, June 2006.


  • Kroll, J. “Seeing Under Sea: Applications of Computer Vision in Underwater Video,” Plenary Address, Harvard Undergraduate Research Symposium, Nov. 2006 (Accepted by faculty review; top 3 of 140 papers).



I sincerely enjoy teaching and am always looking for chances to do more of it. I've been fortunate to have many opportunities to be a teacher, a tutor, a docent, a guest speaker, and many other things. Please contact me if you'd like to know more.

I have taught the following university-level courses:

  • Princeton University, Department of Computer Science. Assistant in Instruction, Computer Science 226: Algorithms and Data Structures. Professor Robert Sedgewick, Instructor. Spring 2011.
  • Princeton University, Department of Computer Science. Assistant in Instruction, Computer Science 432: Information Security. Professor Edward Felten, Instructor. Fall 2010.
  • Harvard University, Department of Mathematics. Head Course Assistant (of 6), Mathematics 23a/b: Linear Algebra and Real Analysis I/II. Dr. Paul G. Bamberg, Instructor. 2006-2007.

Please contact me if you have a specific interest and we can talk.


My curriculum vitae. I cannot guarantee that the one on this website is up-to-date.

I occasionally consult for hire via my consulting vehicle Norwegian Blue, LLC. My expertise spans a wide range of topics in computer security and online privacy and previous work involved automated analysis of websites for privacy compliance and work related to Bitcoin.

For more information, it would be best to contact me.

Contact Me

I am most easily contacted via E-mail at .

If you prefer to send mail of the physical variety, please send it to my department:

Joshua Kroll
Computer Science
Princeton University
35 Olden Street Princeton, NJ 08540