I was one of triplebyte’s interviewers years ago and I can speak to this. In short, you’re right. But two notes:
First, you massively underestimate the range of coding speed you see in an interview. The slowest programmers weren’t senior people who were out of practice. (I interviewed plenty of them). It was people who just seem bad at programming. Like, so bad it takes them 25 minutes to make a hello world program run. (In their favorite language, on their computer and with full access to the internet during the test).
A 2x programming speed difference would have rarely changed the outcome of our overall assessment.
Second, there was an aspect of triplebyte’s interviewing process that I’d love to see replicated elsewhere in the industry that resolves this. And that is, we should be assessing debugging ability. At triplebyte we gave candidates a smallish program (few hundred lines) with 4 bugs and a failing test case for each one. The candidates had half an hour to fix as many of the bugs as they could.
Watching people debug was fascinating.
One clear pattern that emerges is exactly what you are predicting. Smart kids right out of school were great at the programming section. But it was always the more senior engineers who smashed the debugging section. Junior engineers would get lost in the weeds and struggle to get very far in the time we gave them. Some of the senior people I interviewed dived straight in, and even found some bugs we didn’t even know about in our own test.
It seems to me that being able to read unfamiliar code and fix bugs in it is a hard to learn skill that matters on the ground. And frankly I suspect it’s more useful skill than a lot of leetcode problems. I’d rather hire someone who’s amazing at debugging than someone who’s amazing at data structures. Well, I suppose I want one of each on my team.
If I was ever making a programming test, this is something I’d include for sure.
Fair. A good debugging challenge is pretty hard to write well. I remember one of the triplebyte ones I worked on passed through several hands trying to get the calibration right.
First, you massively underestimate the range of coding speed you see in an interview. The slowest programmers weren’t senior people who were out of practice. (I interviewed plenty of them). It was people who just seem bad at programming. Like, so bad it takes them 25 minutes to make a hello world program run. (In their favorite language, on their computer and with full access to the internet during the test).
A 2x programming speed difference would have rarely changed the outcome of our overall assessment.
Second, there was an aspect of triplebyte’s interviewing process that I’d love to see replicated elsewhere in the industry that resolves this. And that is, we should be assessing debugging ability. At triplebyte we gave candidates a smallish program (few hundred lines) with 4 bugs and a failing test case for each one. The candidates had half an hour to fix as many of the bugs as they could.
Watching people debug was fascinating.
One clear pattern that emerges is exactly what you are predicting. Smart kids right out of school were great at the programming section. But it was always the more senior engineers who smashed the debugging section. Junior engineers would get lost in the weeds and struggle to get very far in the time we gave them. Some of the senior people I interviewed dived straight in, and even found some bugs we didn’t even know about in our own test.
It seems to me that being able to read unfamiliar code and fix bugs in it is a hard to learn skill that matters on the ground. And frankly I suspect it’s more useful skill than a lot of leetcode problems. I’d rather hire someone who’s amazing at debugging than someone who’s amazing at data structures. Well, I suppose I want one of each on my team.
If I was ever making a programming test, this is something I’d include for sure.