Purpose of a cover letter in tech, is to get your resume past the HR department. HR is notorious for not understanding tech. If your resume is the only one th

Purpose of a cover letter in tech, is to get your resume past the HR department. HR is notorious for not understanding tech. If your resume is the only one they get, then no need for a cover letter. If they get 100 applications then you definitely do. Where the break line is I do not know. Ditto for the thank you note. If you are the only candidate, then they should be thanking you.