Why Leetcode Style Interview Tests Are Bullshit
by darren horrocksEverybody has heard of the leetcode style interview tests, and given their prominence in the tech news recently, you won’t be surprised to find out that this is another story highlighting their inherent flaws.
Recently, after a remote interview on teams, I was given a set of 3 different leetcode style interview test questions. I was told to take “no more than 3 hours total” and to “write it using typescrypt”.
39 minutes later, I had completed and submitted all 3 tests, and all 3 tests pass all test cases. So now you ask, what’s the problem?
You Clearly Cheated?! (I didn’t)
I was immediately accused of cheating by the VP of Engineering, even though the site has monitoring tools to detect if i was cheating (which if i WAS cheating, which i wasn’t, it wouldn’t have detected anything). The site claims it would detect if I tabbed away, or if I had copied any text out of the test, or pasted anything into the test, I had my doubts, but I didnt need to cheat so why would I.
Apparently, it is impossible, with 20+ years of experience being a professional software developer, to do what their VP of Engineering says should have taken 3 hours, in 39 minutes.
They could provide no proof, the site and its “monitoring tools” detected no selecting of any of the text, no copying of the text, no pasting of anything at all, didn’t detect me tabbing away from the browser. The accusation was entirely down to, others who have taken it, have taken a lot longer, and the VP himself, took a lot longer.
If you and your company put so much weight on these tests, you should:
- Be good at them
- Accept that there are some people, for whom it is possible to be better than you at them
- Don’t accuse people of cheating if you cannot show any evidence that they cheated
In the end, the interviewer (the VP of Engineering) would not back down, they would not accept that I didn’t use an LLM (such as copilot). I offered to do another test with them watching and also offered to show them that IF I was to be cheating, that it would not have taken me 39 minutes, they declined. After the call, I did go back and re-do the same 3 tests with the assistance of gemini, not copilot, because i wanted to see if it was possible to cheat with a tool that more people have access to, it took 4 minutes to complete all 3 tests.
For anybody who is interested in trying the tests they gave me for themselves, these are the equivalent tests on leetcode itself (the site they had me use was a different site that requires a paid subscription by an employer):
How quickly can you get through these in typescript, or any other language, with and without cheating?