I'm sure you've heard the argument, that a Senior Software Developer with a strong AI workflow can outperform several Juniors. But what about a responsible Junior with a strong AI workflow? A Senior could cost over £100k salary. A Junior only costs around £30k a year. Now the choice seems more unclear. Hiring for Juniors has dropped by 60% between 2022 and 2026. Allow me to weigh the pros and cons of each level of experience in more detail, to give us a better perspective on the state of the market.

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Variables in play

We need to start by examining what separates Seniors from Juniors, besides just coding skill. Because we know now that coding skill is becoming less and less important - what matters more is foundational knowledge and system design. And knowing when to trust our own intuition over AI outputs. So let's start there.

Intuition

Through experience, we develop a pattern recognition for future scenarios. Seniors have great intuition, and that's something that you cannot learn from theory. Juniors, however have to build this up which takes time. But in the case of AI responses, and the code AI creates, Juniors who feel the responsibility of this code will be able to tell what the future implications of it could be. It would just take a bit longer than a Senior. Like in the wild, an adult lion would sense dangers much sooner than a younger lion could. But an attentive younger lion, one that knows the stakes, would feel the same sense, just requiring a bit more internal reasoning. The time it takes Juniors to question AI output becomes less through this reasoning, all it takes is deliberate attention to detail.

Oversight

Besides intuition, experience also creates self-confidence. This comes from repeated wins - code doing its job without bugs, and being paid highly for their skills. In almost all cases, a Senior developer would be more confident in their abilities than a Junior. Now, we know which one of these would require more oversight. Companies and teams don't want to babysit their employees, when hiring a Senior, teams trust them to work without mentorship. But that's not to say that Juniors are unconfident, or require supervision. If anything, mentorship can be a boon. A Senior that is a good coach, paired with a Junior who is there to learn creates a perspective differential that amplifies both developers. People who get on with each other boost morale, a team of entirely independent developers isn't a team at all. In a healthy team, everyone is mentoring each other. Oversight isn't a burden, it's just how good teams work. And when it comes to AI, oversight is essential regardless of skill level - no one wants to push misunderstood AI-written code.

Burnout

The bane of all engineers, too much mental energy spent managing and reviewing large volumes of AI-generated code can strain even the most disciplined. Luckily for Juniors, they haven't been developing for as long as Seniors, so they'd have a natural resistance to AI related burnout. But with how the job market is now, I'll say in my experience as a Junior applying for roles, we are definitely not immune to it. Avoiding burnout in general is a discipline in itself, one that differs between individuals. We all react to it differently, and based on years of experience, it can have different weight to it. For example, motivation tends to diminish with familiarity - it's just work to experienced developers at the end of the day. Motivation isn't a driving force behind a Senior's work output at their stage, just like how exercising stops feeling like an achievement and becomes a habit. Juniors on the other hand, benefit from motivation. I'm more motivated than ever to get started in a role and work with a great team - and I'd bet most Juniors feel the same way.

New processes

Building up projects, applying, networking, learning, it takes a toll on the brain. In terms of a job setting, learning AI workflows would come easier to Juniors, as they are much more adaptable to new processes. On a case-by-case basis, there will be Seniors with a passion for learning and new AI tools. But speaking for Juniors who are looking for their first roles, my desire to get into the industry outweighs the fact that I don't have years of habits to unlearn. You'll find a Junior that is willing to learn and adopt company-specific AI workflows more often than a Senior with that same drive. This is most likely down to work availability, Seniors are more in demand - but that hunger to prove themselves is exactly what makes a Junior worth betting on.

Outliers exist for all of these variables, but our biases are based on developers of the past, not necessarily of the present. AI is truly changing the game, but it is not as simple as a tool that amplifies existing skill.

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Output quality vs output quantity

Anyone can set an AI with a task, "build me a website, no mistakes". But what you get is a bland, lifeless website. It is a website at least, so the AI delivered. Although now we have a full website, with unfamiliar code that we have to analyse and debug if errors crop up or if we want to change something. What makes a developer build high-quality systems is now based on AI fluency. We've got things like prompt engineering, AI agents and automated coding pipelines, a new class of tools that can increase output quantity and quality. Workflows are in place decisively to maximise both, but it still takes a keen developer to be able to utilise these tools effectively.

Because AI workflows are still so new to us, there is now an interesting opportunity for both Juniors and Seniors to progress at the same time. What still separates them here is how they adapt the workflows to their specific projects. Like we spoke about in the "New Processes" section, a Juniors lack entrenched habits, and Seniors may strongly defend existing ones. But the differences between them are closer than you think. Coding skill is a bottleneck to Juniors. Being able to play around with and create for themselves Senior-level code gives Juniors a unique perspective - a new way of learning and looking at problems. With the coding skill bottleneck removed, Juniors can now match the output quality of Seniors while seeing in real-time what their high-quality code can do. I've learnt first-hand how AI written code systematically works and have integrated the good stuff into my own processes when coding manually. Quantity is a bit different, Juniors may still need a bit more time to figure out exactly what is going on. But does quantity actually matter much? Maybe for startups with deadlines, or the major AI companies in the race to the top. Quantity is flexible, one day you may need loads, the next you may not need so much. But quality stays the same. Being aware of code quality requires attentiveness and responsibility that anyone can have, not just people with years of experience.

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Responsibilities

Regardless of AI, an employee's job responsibilities scale with their level of experience. Seniors carry the most weight on their shoulders, because they have proven that they are capable. Whereas Juniors have a bit more leeway with what's expected of them. For example, a core responsibility of a Senior is oversight, like we spoke about earlier. Reviewing architecture decisions, catching errors, and steering the direction of the project.

AI workflows shift the responsibilities for both Seniors and Juniors in non-linear ways. Juniors must now be responsible for code that isn't just their own. Seniors are already familiar with this, by overseeing their team, but with AI increasing their work output, that's just another item added to the stack of responsibilities. And more responsibilities means a higher chance of burnout. AI shifts what is exhausting. Less repetitive coding, more key decision-making and prompt refining.

But now that a Junior can code with potentially the output quality of a Senior, the gap between the two roles is starting to lessen. AI increases both the floor and the ceiling of software development, and Seniors will need to keep up just as much as Juniors now if the experience gap is to remain the same.

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Ceiling

So we now have access to a tool that can essentially create code from even simple prompts, what exactly does that do for us? It speeds up coding, which is great. In itself, coding skill alone has a relatively low ceiling beyond a certain point. You most likely won't find too much difference in code quality between a Mid-level and Senior level developer. But what separates Seniors is system design and judgement. An idea doesn't just become a working product, it takes time, planning and execution. Seniors have dealt with this sort of thing before, and know what to do.

It's clear what AI workflows can do to assist Senior developers. Far more high-quality output, and Seniors have the knowledge and judgement to oversee it. But with Juniors, it is more interesting. We established that coding skill is one of their main bottlenecks. With code quality no longer a large issue, what does that unlock for Juniors? Consistent access to Senior-quality code output means enforced industry-standard habits. The time it took for current Seniors to get to where they are from Junior-level is much longer than what we will see from current Juniors on their way to Senior-level. Just like with surgeons of the past versus now. We have much better simulation technology now, allowing trainee surgeons to improve way faster via more options for deliberate practice. This is the key though. Juniors can only improve if they are thinking critically at every stage of the AI workflow. Asking themselves why these certain results would work, and learning from that. The technical craft ceiling has gone. The engineering judgement layer is where Juniors will need to prove themselves. But it is undeniable that the skill gap between Juniors and Seniors is getting closer. It's just that the ceiling has never been about technical skill, only problem-solving abilities.

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Risk

Using AI always comes with a risk of error-ridden code. That's the price we pay for a tool that is so efficient. The balance between AI output quantity and quality here is the deciding factor for what separates the risk from both Seniors and Juniors. Both experience risks with AI-powered workflows, but in their own ways. Output quantity is higher with Seniors, and quantity will always create some sort of risk. Fewer chances of risk with Seniors, but it only has to happen once to cause an issue, and potentially costly damage. Where Seniors mitigate this is through their intuition and risk management skills. Diagnosing, monitoring, and falling back if damage looks like it will occur. Because they do not have much oversight, it falls on them to prevent further escalation. It must be stressful, but they are equipped and capable for dealing with AI-related issues if they happen. Seniors will have their own internal protocols in place should the need arise.

With output quantity being lower with Juniors, the inherent risk of errors is going to be lower. Though a core argument I see with Juniors and AI workflows is something like, "you can't trust Juniors with AI, they don't know what the code means". I understand the weight behind that statement, but it is much more nuanced than that. We've established that motivation and mindset is what drives Juniors to progress. And with risk, it's the same deal. Risk is always going to happen, at every experience level, what separates the tiers is how well you manage risk. Granted, Juniors may not have as much intuition and skill to manage risks when they pop up. But I'd argue, isn't failure what teaches a Junior more? And with the danger from AI-related errors, wouldn't that just emphasise our learning? I'm sure that Seniors have made mistakes in the past, and that they've shipped some risky code. That hasn't held them back, failure is a core part of our learning process. Just like before AI tools, all it takes is for a Junior to acknowledge the issue, and deliberately grow from the mistakes. The risk is always going to be there, AI or not. But a Junior must be more conscientious about the code in their hands.

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Cost vs Value

For the glaringly obvious part, let's talk about costs of Seniors and Juniors. For reference, this will be based on London salaries, so it will be different here than around the globe. We'll compare salaries, recruitment, onboarding, AI tooling costs and turnover. These are averages that I have found, so actual figures will vary a lot. Salary usually only makes up for 50-67% of the cost of hiring a developer, and total investment varies worldwide, but I will convert the rough average to GBP.

Senior Total Cost: £162,000 / year
Junior Total Cost: £63,000 / year

Based on costs alone, a Senior would usually set a company back around 2x-2.5x as much as a Junior. This seems to be universal from what I can tell. This is based on one year, if they stick around for multiple years then the cost will decrease, as it wouldn't need to factor in onboarding or recruitment costs. If they stick around that is. 22% of developers leave within 90 days if there is no structured process, so the cost of onboarding and recruitment will be stacked on top if this happens. The risk of a developer leaving is higher in Juniors, as they may be able to demand a higher salary elsewhere now that they've gained experience. This could still happen to Seniors of course, though you probably won't find it as much. With this in mind, I would estimate that a Senior would cost 2x as much as a Junior. So based on this, would you be getting 2x as much value from a Senior?

Seniors are essential for software. Unique insights and problem-solving skills create demand for them. With a budget of two Seniors, you could also get one Senior and two Juniors, or one Senior, one Mid-level and one Junior for slightly less. It's difficult to compare value. Are two Seniors better than one Senior, and a couple Juniors? Developers don't scale based on experience level, they scale from individual talent. You will find many Juniors that pull their weight despite their title, and you could also find Seniors without as much of a drive. More developers offer more perspectives than fewer, and provide more chances for learning. What if a Senior goes off sick? Now there's only one Senior in that team, or two Juniors. I'm sure a Senior on their own can handle it, but there's a different kind of stress when dealing with something alone. At least two Juniors can bounce ideas off each other, and collaborate. This kind of value scaling is going to be unique to the team. Maybe there isn't as much workload, or maybe there's a lot of demand. Is a larger headcount more important than individual skill? I can't say the answer, all I know is that in my experience in teams, fewer people can only handle so much work, even if they are the best in the world and using AI to assist. More hands is morale boosting, and I know for myself that I'd much prefer a team environment when it calls for it.

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Investing in a Junior in 2026

The pattern now is that companies are either removing developers, or simply hiring Senior developers. There are of course outliers, but we can all pretty much agree that's what is happening. But what's going to happen in a few years, where there have been no Juniors to learn skills in a work environment? The gap between Seniors and Juniors will be huge, many developers will quit, leading to increased demand for developers - meaning they can command more pay. And for what? Because companies chose short-term financial savings over future optimisation?

Investing in a Junior has always had some risk. Short-term, they will make mistakes. But long-term, you've invested in their future. A Junior is progressing in the career they love thanks to you. Imagine you were in their shoes, with constant application rejection, or fear of making mistakes, feeling that they're going to be fired.

Are we comparing a human, Junior's value to an LLM that costs £20 a month? If that's our future, then I'm not looking forward to it. But if you are part of the solution, hiring and training Juniors where you can, then I'd just like to say, thank you. And for all the Seniors out there, I am not diminishing your value. Juniors need you to help them get better.

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TL;DR

AI workflows are closing the gap between Junior and Senior developers faster than most companies seem to realise. Seniors still hold the edge in system design, judgement and intuition - but these are learnable, and AI is accelerating that learning curve significantly. Juniors bring motivation, adaptability and a lack of entrenched habits that make them uniquely suited to AI-first workflows. The cost difference is clear - a Senior can cost 2x as much as a Junior, and that gap only widens at scale. The industry is quietly phasing out Junior hiring, but in doing so it's sawing off the branch it's sitting on. A responsible Junior with a strong AI workflow is an investment not just for the present, but for the future.