There’s a popular take right now that AI eliminates the need for junior engineers. The argument goes: if an AI agent can do the work of a junior developer, why would you hire one? Just give your senior engineers better tools and let them do the work of three people.

I get why that looks good on a spreadsheet. I also think it’s dangerously short-sighted.

And no, I’m not going to make the mentorship argument. I’m not going to make the “moral obligation to train the next generation” argument. Those things matter, but they’re not what keeps a CFO up at night.

Leverage is what keeps a CFO up at night. And if you stop hiring junior engineers, you just handed all of it to your senior workforce.

Junior employees are salary insurance#

Senior engineers know things. They have context, relationships, institutional knowledge. That makes them valuable. It also makes them expensive, and it gives them leverage.

Eventually this turns into a comp conversation. A senior engineer says “I want a 40% raise or I’m leaving,” and the company’s ability to respond depends entirely on what their alternatives look like. If there’s a bench of mid-level engineers who’ve been growing into that space for the past two years, the company has options. They can negotiate from a position of strength. The loss would hurt, but it wouldn’t be catastrophic.

If there’s no bench, because you stopped hiring juniors three years ago and there’s nobody coming up behind your seniors, you don’t have options. You pay the 40%, or you lose the person and spend six months (and a recruiter’s fee) trying to find a replacement at market rate, which is probably even higher.

Junior employees aren’t just doing junior work. They’re a long-term bet. They’re future mid-levels and future seniors growing inside your organization, building context that you can’t hire in from the outside. Every junior you don’t hire today is a senior you’ll have to overpay for in three years.

The pipeline problem is already here#

This isn’t theoretical. We’re watching it play out right now with the boomer generation retiring.

Small and mid-sized businesses across the country are closing, not because the business failed, but because the owner is retiring and there’s nobody to hand the keys to. They spent decades not investing in their talent pipeline, and when it’s time to step away, the business just ends. Everything the owner built, gone. Not because of competition or market shifts. Because nobody was coming up behind them.

This is why the apprenticeship model existed for centuries. It was never about getting cheap labor from a teenager sweeping the shop floor. It was about the lifeblood of the business. The master trained the apprentice because without that pipeline, the trade dies when the master does. Every generation of skilled workers has to produce the next one. That’s not some feel-good mentorship thing. It’s survival.

“But we won’t need the next generation because AI will do the work.” Fine. If AI replaces ALL engineering work, seniors included, then sure, the pipeline doesn’t matter. But nobody is actually arguing that. The argument is that AI replaces juniors specifically.

Which means you still need seniors.

So where do they come from? They don’t show up fully formed. They start as juniors and grow into the role over years. Cut the pipeline and you cut the supply of the very people you’re saying you still need. Ask anyone trying to hire a COBOL engineer right now. The pipeline dried up decades ago, and the few who are left name their price.

A CEO who neglects that pipeline to juice quarterly growth is not doing right by their shareholders. Short-term headcount savings look great on this quarter’s earnings call. They look a lot less great when your senior engineers start retiring and you have nobody to replace them.

The “AI replaces juniors” crowd is proposing the exact same mistake on an accelerated timeline. Stop hiring juniors in 2026, and by 2030 you have a workforce of expensive seniors with no succession plan. Some of those seniors will leave for better offers. Some will burn out. Some will just decide they’re done.

Your senior engineers might not need the job#

Here’s where this gets really interesting for engineering specifically.

Software engineering is one of the few professions where FIRE (Financial Independence, Retire Early) is not theoretical. A senior engineer who bought before housing went through-the-roof, spent a decade earning public-company equity, and kept living like the startup days is in a very different bargaining position from someone still trying to build savings. They don’t need the job in the same way. They work because they want to, not because they have to.

That changes the power dynamic completely.

When a senior engineer who needs their paycheck asks for a raise, there’s a negotiation. Both sides have something to lose. But when a senior engineer who’s already financially independent asks for a raise, there’s no negotiation. They’re not bluffing when they say “I’ll walk.” They will literally retire to a beach and write open source projects for fun. You have nothing to hold over them.

Now imagine your entire senior engineering team is made up of people like this, and you have no junior pipeline coming up behind them. You’re not managing a workforce. You’re managing a group of volunteers. Highly paid volunteers who know exactly how much it would cost to replace them. Good luck with that annual review cycle.

The only counterbalance is having a healthy pipeline of less experienced engineers who are growing into those roles. People who are building careers, who have financial motivation to stay and grow, who give you organizational resilience when a senior decides they’d rather go sailing.

AI will keep getting better. So what?#

I wrote an entire post about why the timeline on that is longer than people think.

But even if AI does eventually handle most of what junior engineers do today, that doesn’t eliminate the economic argument. It just changes what “junior” means. Junior engineers of the future might spend less time writing boilerplate and more time reviewing AI output, learning system design, and building the judgment that makes senior engineers valuable. The role evolves. The need for a pipeline doesn’t.

The hard part is that the old apprenticeship path probably does break. You can’t just hand a junior the boilerplate work that AI now handles and pretend nothing changed. Companies have to design a new path: reviewing AI output, tracing why a generated change is wrong, learning the codebase well enough to know when the agent is making a plausible mess, and sitting close enough to senior engineers to absorb judgment instead of just syntax.

That’s not cheaper in the first quarter. It takes real management attention. But the alternative is pretending senior engineers appear fully formed because the bottom of the ladder got automated. They don’t.

Companies that stop investing in their pipeline because “AI will handle it” are making a bet that AI will be good enough, cheap enough, and reliable enough to replace the entire bottom of their talent funnel, permanently, starting now. That’s a bold bet. And if they’re wrong, they’ve lost years of talent development that they can’t get back.

What this actually looks like in practice#

I’m not saying every company needs to hire the same number of juniors they did five years ago. AI is changing the ratio. A senior engineer with good AI tools probably does absorb some of the tasks that used to go to juniors. That’s real.

But “changing the ratio” is very different from “eliminating the role.” Shopify gets this. We significantly expanded early-career hiring for 2026. This is a company betting hard on AI across the board, and we’re still investing in the pipeline because those aren’t opposing strategies.

Within five years, the companies that stopped hiring juniors will be the ones posting breathless LinkedIn articles about their “talent pipeline crisis” and wondering how it happened. The rest of us will know exactly how it happened. We watched them do it to themselves in real time.