4 Months into a Backend Junior Role: What Should I Study First? (Asking for Help with Interview Questions)
Hello. I joined as a backend developer earlier this year and am now a 4-month newbie starting to get into real work. The company code is Spring-based.
What's most frustrating these days is that I can somehow build features, but when asked "why did you design it this way?" I can't explain. This is about the things my senior asks during reviews.
So I'm thinking of setting this order, and I'd appreciate your opinion on whether the direction is right.
1. Transaction isolation levels — I know the concepts, but I have no sense of when they actually cause problems
2. Index design and reading execution plans
3. Writing test code (right now I barely write any...)
4. Are distributed systems concepts still premature?
I don't even know whether I've set my scope too broad, or whether someone in their 4th month should already know this much. I'd appreciate advice from people in the field.
5 answers
The order isn’t bad, but do #3 before #1. If you study isolation levels without tests, you’ll have nowhere to practice and you’ll forget it quickly. The real learning happens when you add even one integration test to your current code and grapple with the issues that come up.
I'm in my sixth year, and execution plans still feel new to me every time I look at them. At four months in, just wrestling with this much already means you're doing well enough. Don't rush—the most important thing is to build the habit of digging into why for each piece of feedback you get, one by one. You got this!
Number 4 is indeed premature. Things like distributed transactions—there's no need to rush; it's not too late to adopt them when they're truly needed. For now, getting indexes and transactions right in a single DB is far more beneficial.
For #1, don’t just memorize the concept—actually open two sessions and reproduce the lock wait yourself. I was just reading articles at first too, but the first time I saw a deadlock log, it clicked right away lol
Well, is being unable to explain "why it was designed this way" really because of isolation levels or indexes? Honestly, that’s more often due to a lack of requirements analysis and domain understanding... I feel like going through the tech stack first is a bit off track.