While I have not yet written any letters of recommendations for students, but I would be happy to do so for students I have worked with.
I do, however, have a few caveats for ethical reasons listed below (text comes from the Just Math Collective website, but it reflects my own policy)
In general, I am happy to write a letter of recommendation for anyone who has taken a class with me. The purpose of this page is for students to get a feel for the process of asking for one, and to lay out clearly when I will not be willing to write a letter so that no one feels blind-sided.
As a matter of moral principle, I will not write letters of recommendation for programs or jobs involving any of the following:
- Policing (including but not limited to predictive policing, development of algorithms that predict recidivism, etc.);
- Military applications (such as internships at the Department of Defense or any of its international counterparts);
- Weapons manufacturing, broadly construed;
- Intelligence gathering (such as internships at the NSA, FBI, or any international counterpart).
I am very happy to discuss this policy with any student who has questions. Conversations about when and how mathematics should be used are lacking in our community, so in fact I encourage questions and discussion! However, this policy is non-negotiable. Therefore, if it's invoked when I am asked to write a letter, know that it is not personal.
The Just Mathematics Collective has compiled a list of resources for students on making ethical career decisions, which is available here.
Having understood that, if you need me to write a letter for you, please send me an email! This should detail when you need the letter, what it is for, why the opportunity interests you, and why I am the right person to write the letter. Please include clear instructions for submitting the letter once it's written. If possible, please include some sort of resume/CV --- it doesn't have to be official --- detailing your past experiences relevant to the application. All of that will help me to write the most effective letter I can.
Finally, my colleagues and I all write many such letters each year. It's a very important part of our job, and we want to do it as well as possible. So, when requesting letters from any of us, please give as much advance notice as possible, ideally something more than one month.