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Comment by CharlieDigital | Hacker News Reader

You can do code review exercises without larger context.

An example from the interview: the code included a python web API and SQL schema. Some obvious points I noticed were no input validation, string concatenating for the database access (SQL injection), no input scrubbing (XSS), based on the call pattern there were some missing indices, a few bad data type choices (e.g. integer for user ID), a possible infinite loop in one case.

You might be thinking about it in the wrong way; what you want to see is that someone can spot these types of logic errors that either a human or AI copilot might produce regardless of the larger context.

The juniors will find formatting and obvious bad practices; the senior and staff will find the real gems. This format works really well for stratification.

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> no input validation, string concatenating for the database access (SQL injection), no input scrubbing (XSS), based on the call pattern there were some missing indices, a few bad data type choices (e.g. integer for user ID), a possible infinite loop in one case

I'd say all this stuff is junior-level (maybe ~mid for things like user ID integers). It's just a checklist of "obvious bad practices", it doesn't require experience.

The senior stuff is much higher-level: domain modelling, code architecture, consistency guarantees, system resilience... system design in general.

You can do all of that in a code review; the point is that it actually allows for better stratification because you can incorporate different challenges in a reasonable time frame and without having to do take homes and get working environments (you'll end up reviewing their code anyways in a followup session).

You can do it in a real code review. I think his point was that you can't do stuff like "instead of loading a YAML file at runtime this should be generated during build time using the existing infrastructure we have here" type stuff.

But I'm not sure you really need to in a job interview. It's not like you can do that with any other interview method anyway - leetcode also doesn't really touch high level architecture type stuff, and take home problems are also too small (or they should be anyway!)

In my experience you only learn how good developers' architectural taste is by working with them for a long time.

Yes, ish.

In a previous job we did code review interviews. And went the route you said due to the problem I said. And yes, it's a lot better. But what also happened over time was that the bar slowly raised. Because over time the "harder" pieces of that session started to seem rote to interviewers, they became viewed as table stakes.

Mind you this is true of any interview scheme that has a problem solving component to it. I'm not saying that the code review style is extra bad here, just that it doesn't solve this problem.

I think the way to avoid the interviewer's expectations being raised over time is to write down some guidelines for what a successful candidate should be able to do. Even if you don't know how high to set the bar at the beginning, once you've hired someone you'll have at least one example of a good answer.

In theory, you can do code reviews without larger context if the code is carefully selected. Apparently, some companies think any badly written code from their code base can just be selected though.

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