In 1865, the British economist William Stanley Jevons noticed something counterintuitive about the steam engine. As engineers made it dramatically more fuel-efficient, Britain did not consume less coal — it consumed vastly more. Cheaper energy per unit of work meant industrialists deployed steam everywhere they previously could not afford to. By 1900, British coal consumption had roughly tripled. Jevons called this the "rebound effect." Economists now call it the Jevons paradox: when efficiency lowers the cost of a resource, total consumption can rise rather than fall, because demand is elastic enough to more than absorb the savings.
The argument that this pattern applies to software development is circulating widely enough that you have probably encountered it. The claim is roughly: AI agents lower the cost of writing code, so the world will demand far more software than it currently gets, and that expanding demand could require more developers — or at least as many — rather than fewer. It is a more sophisticated argument than the usual "AI will create new jobs to replace old ones" optimism, and it deserves a serious look. It also has real weaknesses.
Where the analogy holds
The structural parallel between coal and developer time is not superficial. Developer capacity has functioned as a genuine bottleneck — not a fixed one, but a persistent one. Most organizations maintain a feature backlog that is longer than their team can address. One survey of enterprise software teams found that nearly three-quarters of organizations wanted to build more than ten new applications in the next year, and 45 percent wanted to build more than 25. The gap between that ambition and what ships is not primarily budget; it is engineering capacity.
When a resource is genuinely bottlenecked and demand is elastic, reducing the per-unit cost tends to unlock latent demand rather than simply shrink total spend. The history of software supports this reading. Personal computing made programming cheaper and more accessible in the 1980s. Rather than saturating demand, it created millions of new applications, new industries, and new categories of software that had not existed before. The internet did the same in the 1990s. Cloud computing removed infrastructure cost as a barrier in the 2000s; the result was not fewer developers but more startups, more SaaS products, and new verticals that embedded software where none had existed — agriculture, manufacturing, healthcare.
GitHub's data for 2025 showed approximately 43 million pull requests merged, up about 23 percent year-over-year, alongside roughly a billion commits, up about 25 percent. Some share of that growth is AI-assisted output, but the absolute volume continues to expand. The Bureau of Labor Statistics projects software developer employment growing around 15 percent through 2034, well above the average for all occupations. These numbers are consistent with, though they do not prove, a Jevons dynamic at work.
GitLab's 2025 DevSecOps survey of roughly 3,200 practitioners found what it called an "AI Paradox": AI tools accelerate the coding phase but simultaneously create new bottlenecks in testing, security review, compliance, and cross-team coordination — costing organizations close to a full workday per engineer per week in follow-on work. Sixty percent of surveyed teams used more than five different development tools, compounding the coordination cost. The efficiency gain in one layer exposed friction in the layers around it.
Where the analogy breaks down
The Jevons paradox is not a law. It describes a condition: when demand is sufficiently price-elastic, efficiency gains drive net consumption up. But not all resources have elastic demand, and not all uses of a resource do either. The economist Philip Hanser, quoted in a Northeastern University analysis of AI and Jevons, points out that the outcome depends critically on whether the technology functions as a complement (making existing use more productive) or a substitute (replacing the use outright). Steam engines made energy-intensive industrial production cheap enough to expand into new markets — that is the complement story. AI agents might instead substitute for entire categories of software work without generating equivalent new demand. The distinction matters and is not yet settled empirically.
There is also a composition problem that the aggregate demand argument skips past. Even if total software demand grows and total developer employment holds steady, the distribution of that work shifts. The tasks that AI agents perform most reliably — generating boilerplate, writing unit tests, translating specifications into implementation — are precisely the tasks that historically served as the entry point for junior developers. According to data collected from hiring platforms in 2024 and 2025, entry-level software developer postings had declined roughly 60 percent from their 2022 peak. Employment for developers aged 22-25 fell close to 20 percent from the same peak. Microsoft executives have publicly acknowledged concern about AI displacing entry-level coding roles. Anthropic CEO Dario Amodei said in 2025 that junior developer positions are "in the crosshairs" of automation.
The Jevons argument can simultaneously be correct at the macro level and punishing at the micro level. Total developer employment might grow or hold flat while the lower rungs of the career ladder compress. That is a distributional problem that aggregate optimism does not resolve.
A further wrinkle: the elasticity of software demand is not uniform. Demand for mission-critical enterprise software, regulated-industry platforms, and complex infrastructure has historically been less price-sensitive because the constraint was never primarily cost — it was organizational change management, regulatory approval, and integration complexity. Making code cheaper to write does not necessarily accelerate deployment in those contexts. The friction lives elsewhere.
What this realistically means for developers
If you are an experienced developer, the Jevons dynamic is probably your friend. Your leverage increases when AI handles the implementation layer and your comparative advantage shifts to architecture, judgment about what to build, integration of AI-generated components, and review of correctness and security. A survey finding that 42 percent of companies anticipate needing additional IT specialists because of AI adoption is consistent with this: the coordination, review, and direction overhead grows with output volume.
If you are early in your career or trying to enter the field, the picture is more complicated. The traditional on-ramp — junior roles where you build competence by working on contained, well-scoped tasks under senior oversight — is under real pressure. Some companies are explicitly reconsidering junior hiring. The practical response is not to wait for the market to sort itself out but to treat AI tool proficiency as table stakes from day one, build a portfolio that demonstrates judgment rather than just execution, and seek roles in organizations that are expanding their software ambitions (and therefore their total demand) rather than those trying to hold headcount flat while AI absorbs the output.
The sector matters too. Industries that are underserved by software — healthcare, agriculture, small-business operations, physical logistics — represent genuine latent demand. If AI lowers the cost of building software for those markets, Jevons dynamics are more plausible there than in markets already saturated with developer attention.
The honest summary is that neither the optimistic nor the pessimistic reading is well-supported by current data. GitHub's commit volume growing 25 percent year-over-year is real. Entry-level posting declines of 60 percent from peak are also real. Both things can be true: aggregate demand expands while the distribution of who captures it changes structurally. Jevons gives you a useful framework for thinking about why AI might not reduce total software work — but it does not tell you whether the composition of that work leaves you better or worse positioned than you are today. That depends on where you are in your career, what sector you work in, and whether the organizations you work for respond to falling code costs by building more or by cutting headcount.
William Stanley Jevons was right about coal. Whether he is right about developers is a question that the next five years of hiring data will answer more clearly than any analogy can.
Originally published at pickuma.com. Subscribe to the RSS or follow @pickuma.bsky.social for new reviews.
