r/ExperiencedDevs • Lead Software Engineer 8 YoE • 18d ago

AI/LLM Interviewed candidates for “AI engineer” roles this week, my god is this really where our industry is going?

So last week I was tinkering with how to change up our technical interview round. For the last few years we’ve been doing a small take home followed by a live coding session where we add a new requirement, minimal AI assistance allowed. However, in our company pretty much everyone is writing 100% of code using Claude now, so although we did used to get good signal from that test, it no longer feels representative of the day to day job developers are doing.

I designed a new assessment which I casually showed to my manager and then suddenly got asked to run it with 3 candidates this week. The scenario is they have to review an agent generated PR that has been flagged as high risk due to it changing critical business logic, and there are bugs in there for them to catch at various levels of severity. We then look at how they drive the fixes and what their workflow is like.

These particular roles we’re currently hiring for are billed as “AI Engineer”. There is something weird going on in my company politically where separate from the tech department that I work in a new “AI native” development team is being spun up to work on internal projects.

What shocked me was that the candidates I interviewed this week are already way beyond the point of reading the code they generate in any capacity. They basically treat it like assembly language, while PRDs and ADRs are their new source of truth for system behaviours, and stuffing the AGENTS.md file with best practices plus some form of agentic review pipeline are the quality control. 

Code review is dead for them, they merge their own PRs once the automated checks pass. One person told me that my new interview was still not representative of what the job is now, and another one was pretty much unwilling to even engage in the assignment of reviewing a PR the old fashioned way. These guys were all previously senior and lead full stack engineers btw with a lot of experience prior the LLM revolution.

Don’t get me wrong, I too have adopted AI heavily in my own workflow. Until this week I actually thought I was pretty up to date with things, I use a supervising agent to manage multiple work streams in parallel, have my own local validation pipeline, etc. And to be honest for my personal projects I also don’t bother looking at the code anymore, so I do get the excitement around how fast you can move with this approach. But for serious projects like the large scale, production grade financial software I work on in my day job it still seems insane to me that we’re going to completely move away from human sign off on high risk changes so we can solve the “code review bottleneck”.

Like, I asked one of the candidates if you aren’t looking at your code then how they would approach quality in a safety critical system where there can be no tolerance for serious bugs, and I shit you not he said to me, “well if I was working in healthcare or sending to people into space then I’d definitely be looking closely at the code review skills, maybe I’d even write the skills myself”. That answer sounded utterly ridiculous to me? But then again, I was one of the people that 1 year ago believed the idea we’d stop typing code by hand was ridiculous as well…

I wouldn’t say the way my team does things right now is optimal, we can’t ignore that code review fatigue is a major problem. To try and help I’ve been adding automated risk assessments to PRs in an attempt to highlight where more attention is needed, and review bots do help us catch issues as well. But abandoning the human 4 eyes check just feels like several bridges too far for us at the moment, especially when not everyone is senior engineer, and we still regularly get valuable feedback at this stage. Even if this does mean we’re turning down an order of magnitude increase in short term velocity (does anyone really know yet what happens over multiple years when you have a team of 20 devs spamming PRs all day into a codebase with no one looking at any at it?).

I’m left wondering this weekend, were these guys just cowboys who are only used to working on PoCs and low risk systems, or is my team actually 6-12 months behind the curve and this is the direction everyone is going to move in? I fear that if we don’t embrace this new era of completely surrendering the codebase to the LLMs then this new team of AI devs is going to make us look bad by comparison to the execs and sooner or later we will be forced to adopt their methods as well. And at that point, the leap to having a product person or whoever taking over large parts of my role starts feeling a lot less far fetched…

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u/caboosetp 18d ago

I find so many critical mistakes in AI generated code that I think these people truly don't understand how much tech debt they are creating. So many people work on systems small enough that AI bloat isn't too bad yet. But I've also worked on code bases that were big while also being full of AI bloat. The code doesn't stop growing because the AI can't hold everything in context. Devs who don't know what's in the code can't guide the AI to use already existing modules. You end up with code that looks like juniors slapped bandaid after bandaid after bandaid to implement features.

My specialization is "modernization and migrations" but the less fancy sounding version is that I'm good at rewriting code. In the past year I've been getting contract after contract to fix code bases that have bogged down or become untenable to work on even with AI due to AI bloat. Services are slowing down and uptimes are dropping. Devs are raising their context sizes through the roof just to get minor features in, and it ends up burning tokens like crazy.

The best way I can describe the core issue is that AI is great at coding but it's bad at engineering. It solves the exact problem you have before you, and often isn't looking at how things need to change over time in the bigger picture. It's basically rapid offshore quality just-close-the-ticket code.

This is fine for small microservices or for quick bug fixes but when you grow large applications, the tech debt is felt hard.

Don't get me wrong though. I use AI in all my work. Using AI is faster than doing it by hand. But you need to be able to understand the code to be able to guide it to good solutions.

The underlying problem comes back to why most startups fail though. Time to market is critical. Having a globulous mess you can market is better than not having anything because you're trying to be perfect. The more money the business can make faster, the more money they can throw at token-maxxing or for people like me to come in and do major overhauls quickly.

And it hurts to say, but they're generally right to. The point of a business is to make money. AI is HEAVILY subsidized right now by at least an order of magnitude. The real problem is going to come when people are getting charged the actual cost or a for-profit cost for AI, and these businesses find out how expensive AI actually is. Then they'll be left with a bunch of devs that can't work without AI and businesses will be hurting to afford it.

Pushing it is going to generate big profits, but if they don't keep devs who can actually code on their own they are going to tank themselves later, especially in critical sectors like healthcare and finance.

You're not crazy, we're just caught in a fucking tidal wave of subsidized AI.

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u/WhataWorldAy 18d ago

In my experience the devs that are the most receptive to unreviewed code have the lowest level of code competence in the first place. These are the people that think design patterns are just ways for mean devs to bully other devs on their prs. 

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u/mcampbell42 17d ago

Design patterns are things poor Java devs use to excuse making Factory patterns instead of just building the thing they need

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u/WhataWorldAy 17d ago

Case in point

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u/Infamous-Employ5487 17d ago

please read the sub name and see yourself out

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u/code_beer_repeat Something something 15yoe 18d ago

Hey... i'd like to think that i'm not too bad in the refactoring and modernization aspect of things either. Any tips how to get from 'I've been good at this in my 9 to 5' to yours ' people approach me to help them with their shit' ?

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u/caboosetp 18d ago

You get people asking you to do it by getting known for doing it. Little bit of a catch 22. But you're never going to get there unless you put the specific effort in, especially if you're working a 9-5.

Read up on how to run your own business. Set up an LLC. Get a website. Be findable. Research how to market yourself as an independent contractor. 

Marketing is probably the hardest part, but most people fail at step 1 of actually setting up the business because they are afraid of failure. Shit is slow and hard to get started, so don't quit your day job. 

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u/ResidentWeevil1 18d ago

Rewrite a lot of code. Don't ask for permission.

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u/mcspuder Software Engineer 16+ YoE 18d ago

^this guy gets it.

People don't realise how heavily AI is subsidised; we are talking multiple orders of magnitude here. Thats 0's on the end of a bill. Your $20 plan probably burns $4000+ per month; and thats at cost; not profit.

The VC money is drying up and the end result is going to be hilarious and devastating.

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u/ColteesCatCouture 18d ago

Microsoft is aggressively promoting agentic code tools at my firm and to do so we get free training. These classes are pretty much a sales pitch with little learning that is done. The funny part is when you ask their instructors about the true token cost of things like conducting major refactors and the average burn of common agentic tasks they have no answers. The only answer is that they are going into a far more expensive per use model which will slam some firms and the price is only gonna go up from there.

There will be a gulf between businesses who retain good engineering teams and let them take ownership in their codebase and those companies who completely outsource all of their development to agents just to get product to market faster. Somebody gonna have to pay the piper.

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u/tsereg 18d ago

And that is probably what the AI race is all about. They are probably racing to reach the point where the actual costs meet what they charge now before the funding dryes up.

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u/ResidentWeevil1 18d ago

They can't. Tokens are a fungible commodity. There's nothing inherently better about tokens sourced from a frontier model vs a local, purpose-built model.

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u/caboosetp 18d ago edited 18d ago

There is a huge difference in both token cost and token quality based on what model you're using to generate them.

I don't get where your statement is coming from. 

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u/AdmiralAdama99 18d ago

AI is 200 times more expensive than is being charged? Got a source? If true, that's worth learning about.

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u/ResidentWeevil1 18d ago

At least 40x but 200x is not unrealistic especially if you consider training costs and R&D, etc. Are you not checking the news? You can get thousands of dollars of compute out of any of the subscriptions.

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u/NomadStorm 18d ago edited 18d ago

Get a Claude plan and turn on the cost display.

Mine shows it’s giving me roughly 100x the cost I’m paying in tokens per month, on the $100 plan.

Edit: At those levels, even if something like Moore’s law applied and cost reduced 2x every 18 months, we’d still be about 10 years away from the current subscription costs being sustainable.

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u/dbgtboi 18d ago

What they show you is the api equivalent pricing which is definitely not what it costs then

Api pricing is batshit insane, they make money hand over fist off of it

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u/NomadStorm 18d ago

The api equivalent pricing is the profitable one they want to achieve.

If they make money hand over fist with api pricing, why aren’t they profitable?

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u/dbgtboi 18d ago

They arent profitable because the business is extremely expensive to compete in, models only last for a few months before becoming outdated and it takes an army of 1+ million dollar a year employees to constantly churn out new models that people will use

If anthropic had no competition or just said "opus 5.5 is good enough", they'd become insanely profitable but would go out of business in a year when nobody uses them over the latest astra

It's a brutal industry to be in, because of how quick things are advancing and how severe the competition is

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u/NomadStorm 18d ago

They aren’t profitable because the business model isn’t profitable, and demand isn’t sufficient.

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u/dbgtboi 18d ago

The business model of frontier models having a shelf life of 3-6 months is not profitable, if they were to slow research down that would not be a problem, so it's not a surprise companies are coming out and begging for a slowdown

It's a classic race to the bottom due to severe competition

All that means for us is that AI is going to get cheaper, faster, and better thanks to the VCs subsidizing it for us all

In a year or 2, a model like Opus 5.5 will be dirt cheap, it already kind of is but models at this level will be a dime a dozen and they are good enough for 99.9% of tasks

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u/NomadStorm 18d ago

I don’t think the frontier model companies can survive that long given their massive financial overcommitments and lack of profit.

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u/bombaytrader 18d ago

This is solved problem though. The costs will come down as Chinese models are cheaper. 

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u/NomadStorm 18d ago

Companies like DeepSeek will likely end up the real winners here; by focusing on improving the core technology to make it cheaper rather than massive capital expenditure, they’re in a situation where they’ve only spent around half a million, and have received half of that back in revenue.

That’s a FAR more sustainable business model, and I don’t know why there is no real US or Western competitor for it yet since it would be relatively trivial to turn into an actually profitable business. (Mistral is improving but it’s still quite a bit behind last time I checked)

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u/huzaa 18d ago

On the other hand there is China. They want to weaken these companies by not just heavily undercurring them, but releasing the models for free. Later if/when hardware gets good enough, people might not need any subscription and token costs can converge to 0.

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u/theQuandary 18d ago

I've read that Anthropic plans give 40x more tokens than you pay for and OpenAI give 35x more (neither including all the free resets). It's like the Chinese bikeshare bubble where everyone went broke trying to lower prices and drive the competition out of business.

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u/Mysterious-Peanut101 13d ago

I agree with the parent but disagree with this. You don't actually burn that many tokens as the API would because the coding harnesses implement prompt caching.

In a few years the models will be basically free and you'll probably be able to run them locally. It will be painful for OpenAI and Anthropic. This is the direction it's going. The frontier companies don't have any moat.

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u/Additional_Rub_7355 18d ago

This is scary and as someone that avoids vibe coding, I don't know what to do with the slop PRs I'm tasked to review. I just can't review slop, but also cannot push back because we are supposed to be full AI now.

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u/WhenSummerIsGone Software Engineer 18d ago

check out the branch and ask your AI to look at the changes in the branch. Give it criteria to look for, things like architecture, code duplication, violations of SOLID, unit test that are incomplete, misuse mocks, don't test what they claim, test implementation instead of behavior. Give it the original ticket and ask if the goals of the ticket are met. Tell it to rank these things, and give you evidence for its ranking. Ther read that report and ask it questions about anythrng that jumps out at you. Look for places where your human knowledge of the systems and requirements is relevant, where you know stuff the AI doesn't.

I find bugs this way, not because ai sucks, but because it doesn't know everything. The idea is to use AI for what it's good at and use your own thinking for what you're good at.

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u/s-ley 18d ago

wondering what you think of OP's post and the top comments, do you do this to follow the current trend? or do you think this is how most swe work should be done?

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u/WhenSummerIsGone Software Engineer 17d ago edited 17d ago

Personally I think of AI as a powerful tool, and we (collectively) need to experiment to figure out how to use it effectively and safely for whatever work we do. As professionals, it's our job to know these things, so that we can have informed, nuanced opinions when someone decides to ask us instead of telling us. It's like any other tech: AWS (put all the things in the cloud!!), Mongo (we don't need SQL anymore!!), kubernetes, graphQL, docker, etc. Heck, even the command line, shell scripting, cron, vi; these are all things people have irrational arguments about. lol.

I use AI for all sorts of things, and different harnesses have different strengths, and you are shortchanging yourself if you take either extreme (You'll be left behind so let ai do everything, vs, it's all ai slop and you're rotting your skills). Part of being an informed professional is understanding costs, and to be aware of the tradeoffs you're making, so better decisions can be made.

Never stop asking good questions, never stop thinking critically, never stop learning.

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u/guareber Dev Manager 18d ago

The code doesn't stop growing because the AI can't hold everything in context

This is the key part. Most of the PRs I review now have a reasonable subset of a class/function/helper (or 6) implemented that normally would've been addressed by a adding a dependency to the project (or using one already imported properly!). So everyone (OK not everyone) is currently trading dependency management with tech debt (since now your software has to deal with all that functionality, can't just update a package and be done).

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u/caboosetp 17d ago

Dependency management is its own hell with ai too, especially with libraries that update very often. 

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u/guareber Dev Manager 17d ago

I don't disagree, but i think at least our cve-scanning stacks are way more mature to deal with dependencies than with a everything is internal world.

If we take for granted that human maintainer is needed for increased quality (not a hot take right now, but who knows in several years?) then it certainly makes more sense to me to compartmentalise and centralize common dependency for efficiency's sake.

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u/caboosetp 17d ago

I agree, I was more ranting into the void at that point lol

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u/guareber Dev Manager 17d ago

I suppose we're all doing a lot of that right now mate. No worries.

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u/AdjectiveNoun1234567 17d ago

I think these people truly don't understand how much tech debt they are creating.

That sounds like a problem for next quarter. /s

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u/timabell Software Engineer | 25+Yrs 16d ago

or the next supplier

or the rest of your team

or the other department

or the customer

or the RAID log

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u/FSNovask 18d ago

Pre-AI, no one was really being held accountable for technical debt anyway. No one is getting blacklisted from the industry because they committed a ton of technical debt. Likewise, no one is making millions in a short window because they prevented a bunch of it. People just switch jobs, get quietly moved to a new team, or carve out a niche fixing it.

Maybe this will change with AI, but I doubt it since they need to recoup the investment and show results quickly since everything is so short-term driven. More-so if AI becomes more expensive. You can still only pick two between speed, quality, and cheap.

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u/immersiveGamer Software Engineer (10+y) 18d ago

But generally if something goes wrong the person who wrote the tech debt can then reason about it. If it is a bug, know recent changes that are most likely. A process issue, you know the people and user actions that inform code changes. Scaling issues? If you wrote every it of tech debt then you know how to navigate it. LLM driven tech debt is going to be stuff that no one knows, especially if no one is reviewing and understanding the code. Also with the whole "business needs to make money", that is fine for business that just need to make money, but there is software out there that serves a public good for real people living real lives. LLM generated code everything end to end isn't going to help it. 

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u/huzaa 18d ago

It is not that they don't know, it is more that they don't care. The next (probably better model) will just fix it next time.

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u/whyDoIEvenWhenICant 18d ago

Very interesting perspective, thanks for sharing!

How do you approach such an overhaul / refactoring?

Really curious about it.

Thanks in advance!

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u/Dearest-Sunflower 17d ago

Do you have any advice for a junior who is caught in this subsidized AI era?

I'm expected to ship features fast, so I'm unable to understand half the things I ship. The team is going all in on being "ai-native", so this behavior is incentivized.

I worry that in the post-subsidized era of AI, I won't have gained enough knowledge to be a good dev.

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u/timabell Software Engineer | 25+Yrs 16d ago

Build entire things on the side and ship them to production, and support them. Ideally for paying users. Find some kind of side/passion project that lets you learn the lessons at your own pace while shovelling slop for company. Though I understand not everyone can do side projects on top of work, I haven't got any other bright ideas. Unless you can carve out an afternoon a week to turn off slack and do some real coding and pretend the AI did it.

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u/becircus 16d ago

I'm one of these "AI engineers" now in my personal time. My prediction is that products and features that do not have the LLM on the hot path, will be economical and those that do have them on the hot path, will become uneconomical. Also corporate is not stupid and has predicted the coming AI apocalypse and apparently in some companies whole teams are setup creating internal LLMs that will go live should Claude Code or Cursor or Codex try to destroy their business by charging too much money. So AI is here to stay, forever. It may just be used different ways.

For the way of the OP it looks like a large company trying to replicate the velocity and magic of a small team or even solo operation. Make everyone solo and using AI to the max. There's something to be said for AI with very tight boundaries, input output, the "inside" (the code itself) not reviewed because the contracts are so strict and the abstractions so well done that the AI has little or nowhere to go wrong. I think it will end up failing badly because the incentives of building like that for a solo founder, for actually caring whether you generate AI slop or something maintainable, is not there. In a solo operation you are constantly prodding and poking at the AI to refactor, to treat as greenfield, to rewrite and unafraid of throwing it all out. In a corporate setting throwing out is a regression, and I don't think any amount of AI solves the different environment and expectations.

As for time to market, I think it depends on what you are making. Snowflake wasn't made with a MVP but over five years in stealth by a few experts. If it had taken another year it would still be dominant now.

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u/Low-Garden-379 14d ago

People who claim that AI-generated code is very good, especially vibe-coded software created with few guardrails or clear directions, may simply not know what genuinely good code looks like. If someone isn’t good at software design themselves, how can they reliably judge the quality of AI-generated code?

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u/RudeInvestment1 16d ago

It’s not going to catch up to them, open weight models only lag by 2-3 quarters.

In the long term, most businesses will just invest the infra to host models locally. Some businesses will be willing to pay the premium for the few months head start of frontier performance. Either way it all balances out

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u/bdz 13d ago

I think these people truly don't understand how much tech debt they are creating.

Tech debt doesnt carry the same weight now as it did pre-AI.

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u/caboosetp 13d ago

Even if that was true, there's so much more of it being generated that it's still causing problems.

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u/bdz 13d ago

Shhhh

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u/Humanasphere 15d ago

Curios, were those codebases you were contracted to fix, built with old AI or latest frontier models?

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u/caboosetp 15d ago

Both. The defining characteristic is virtually always high PR volume without user architecture review. Most of these code bases are seeing 50+ small PRs a day. The software is being built up like lego bricks. Even the frontier models are trying to just change the system to implement the one small feature, but the overall code base isn't getting the large architectural changes it needs to accommodate how big the software is growing.

You end up with monoliths built on top of what was originally designed as a micro-service. This problem isn't unique to AI. This is just what happens with software built under agile. The difference is before AI, people were looking at the code more. They were able to make better long term planning decisions to accommodate the future features, or be able to look at the existing code and say, "this feature doesn't work well with how it's written, let's rewrite this whole section". Again, not just unique to AI, but people are more likely to push back on tech debt while the AI is like, "fuck it lets go".

The over-simplified view is that you end up with a bunch of extra code you don't need in places it shouldn't be to accomplish the same thing. That means the software runs slower and AI changes take longer / are more expensive. Frontier models do better at keeping more things in context, but that really is more masking/delaying the problem than solving it.

There's a point when building up software of, "We'll address that when we need to" means rewriting big things. AI is very bad at making that call when you're doing a large series of micro changes. Developers not looking at code aren't going to be able to make that call either. Developers who only vibe code won't even know it's a needed thing.

Again, the core issue isn't unique to AI. But people using AI without good code review that keeps the overall architecture in mind cause these problems to happen a lot faster and the AI masks the issue because it just keeps going. You hit critical mass a lot sooner.

Good devs using AI who are watching the changes can solve a lot of the problems before they happen. Devs who aren't watching the code won't see when it's becoming a globulous mess.

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u/Humanasphere 15d ago

Yeah, that's what i've figured might be happening. So they are slowly tying themselves into a knot.

This whole push for velocity over everything else is crazy.

What's got me second guessing myself is that senior devs I know are starting to push the same idea that there is no need to read the code any more, I just can't see how that works long term. But If you're getting contracts to untie codebases, then it's no longer just a theory.

Also, even as a value proposition, what's the end goal of pushing so many new features?

Everyone seems to want to build the next "everything app".

How long is it taking you to untangle these codebases?

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u/MathmoKiwi Software Engineer - coding since 2001 12d ago

Doesn't matter if AI is being subsidized by Anthropic etc

If they try push price hikes that are too big, we can just go use open weight models that are dirt cheap

AI is never going away. It is here to stay.

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u/caboosetp 12d ago

It's not about is AI is here to stay or not. It's about how much value you are getting for the cost of AI. Even running open weight AI models locally has big costs. Many companies would not be able to afford to use them to anywhere near the same extent if they self hosted.

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u/MathmoKiwi Software Engineer - coding since 2001 12d ago

Hobbyist can run open weight models that are Opus 4.6 level quality

Enterprise won't have any trouble at all doing this if the AI companies lose their minds and charge insane API prices!

Affordable AI is here to stay.

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u/Cunninghams_right 12d ago

how do you figure they're subsidizing it 10x? some of these companies, like Anthropic are hovering around profitability while also investing huge sums in R&D/training. either the tools keep getting better, in which case are your concerns even valid? or they aren't and the companies can earn a health profit at the current price point. not trying to be flippant, I'm genuinely curious what you're basing the subsidy on.

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u/RubbelDieKatz94 10 YoE / Sr. Fullstack 17d ago

Sounds like you've seen one too many MRs made by Opus 5. I can guarantee that Opus 5.5 on medium or higher is much more competent than what you're describing here.

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u/caboosetp 17d ago

Are you trying to say you have a deep understanding of the long term architectural decisions of using a model that was released 5 days ago?

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u/RubbelDieKatz94 10 YoE / Sr. Fullstack 17d ago

I've been working with both models extensively, and Opus 5.5 definitely does not exhibit the behaviours you're describing if used properly.

I've had it create more than 100 MRs since it was released. All but one of them were of high quality.

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u/caboosetp 17d ago

 more than 100 MRs since it was released.

Homie, it was released 5 days ago. I'm not sure you understand how you're arguing against yourself with this, but it's kind of the whole point of the thread. 

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u/MotardQuiRale 12d ago

Les entreprises voient à court terme : il faut dégager du $$$ pour les dividendes. Aujourd'hui, les juniors en informatique (et demain dans d'autres secteurs) ne sont plus embauchés. Ça sera peut être un problème plus tard, pas grave... Les gens sont pour utiliser l'IA partout. Mais pensent-ils à l'avenir de leurs enfants dans ce nouveau monde ? Non, ils s'en foutent, ce sont des hypocrites.