The process took 2 months. I interviewed at Proofpoint (Sunnyvale, CA) in Sep 2019
Interview
The typical 3-round interview process.
1. Phone screen (behavioral only, discussed background). Roughly 30 minutes.
2. Video call/screenshare programming with one senior developer. Roughly 1 hour.
3. On-site interview at Proofpoint offices in Sunnyvale. Roughly 6 hours.
Interview questions [5]
Question 1
Write regex for any combination of a and then b where b can appear anytimes but a cannot appear consecutively. Don't use lookahead/lookback, only the *, ?, + characters and the union and grouping.
Given an input string and a second string called "alphabet" that consists of lettters, sort the input string such that the input string consists of the letters sorted by the 'alphabet' (and any characters in the input string not in the alphabet appear in the order they were given).
Took nearly 2 months, 1 call with recruiter, 1 call with hiring manager (slightly technical), 1 call with staff engineer and 2 seniors, 1 more in person interview with 2 senior AI engineers.
I applied online. I interviewed at Proofpoint (Fort Collins, CO) in Apr 2026
Interview
Did a two hour coding project which was cool, for the initial job screening. It involved creating a app in C# and seemed to go pretty well. However the ghosted me after doing it, followed up on three separate occasions no response.
I applied online. The process took 1 week. I interviewed at Proofpoint (Toronto, ON) in Jun 2025
Interview
I had an interview with a recruiter. It was a typical HR interview and it lasted about 30 minutes. Unfortunately, I was ghosted even after I sent a follow-up email.
Software Developer applicants have rated the interview process at Proofpoint with 2.8 out of 5 (where 5 is the highest level of difficulty) and assessed their interview experience as 38% positive. To compare, the company-average is 44.8% positive. This is according to Glassdoor user ratings.
Candidates applying for Software Developer roles take an average of 33 days to get hired, when considering 27 user submitted interviews for this role. To compare, the hiring process at Proofpoint overall takes an average of 29 days.
Common stages of the interview process at Proofpoint as a Software Developer according to 27 Glassdoor interviews include:
Phone interview: 28%
One on one interview: 18%
Presentation: 16%
Skills test: 10%
Group panel interview: 8%
Background check: 6%
Drug test: 6%
IQ intelligence test: 4%
Other: 4%
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