Chapter 11 / Essay
Chapter 11 № 11 · 2026

In five years, the main changes
complete — irreversibly.

The chain of change, a roughly five-year horizon, irreversibility — but bounded to software development

The final chapter of the Software sub-series. The structural changes shown across the previous ten chapters are not independent — they chain together. The chain completes its main part in about five years, and once a structure has moved, it does not move back.

But this "complete replacement" only applies in the specific domain of software development. The boundary is made explicit in the second half of the chapter.

The chain of change

Put the claims from Chapters 1 through 10 back in the order in which they cascade.

These are not independent observations. They cascade from one fact — AI taking execution — in chain.

flowchart LR AI["AI reaches human-top
execution capability
(Ch 1)"] Coder["Coder role
goes away (Ch 3)"] Builder["Builder demand
(Ch 4, 9)"] Customer["Customer
self-build (Ch 5)"] SIer["SIer
shrinkage (Ch 6, 7)"] Lock["Lock-in
dissolves (Ch 8)"] Industry["Industry
transition (Ch 10)"] Done["Main changes
complete in ~5 years"] AI --> Coder AI --> Builder Builder --> Customer Coder --> SIer Customer --> SIer Lock --> SIer SIer --> Industry Industry --> Done classDef good fill:#e8f5e9,stroke:#7a9a6d,color:#3a4d34 class AI,Coder,Builder,Customer,SIer,Lock,Industry,Done good

Within the chain, what moves fastest is new projects and extensions. What moves slowest is full replacement of core business systems. But both point in the same direction, and the direction does not reverse.

Why only coding moves to complete replacement

This is where the scoping of the sub-series needs to be made explicit.

Software development is a broad field — requirements gathering, design, coding, testing, deployment, operations, incident response, stakeholder coordination. What AI fully replaces is only the "coding" inside this list. The reason: two conditions hold at once for coding:

  1. The rules are explicit — language specs, standard-library APIs, type systems, syntax — all defined formally and unambiguously. There is little interpretive room for "the correct way to write it."
  2. Correctness is verifiable — whether code compiles, whether tests pass, whether a competitive-programming problem is solved — all checkable mechanically.

When both conditions hold, AI receives, during training, an enormous volume of feedback both on "did it follow the rules" and "is it correct." That is why AI reaches superhuman levels in the coding domain.

AI reaches superhuman levels in domains where the rules are explicit and correctness is verifiable. "Coding" inside software development is the textbook case.

The other parts of software development — requirements, design, operations, incident response, stakeholder work — carry the same structural 1% problem we will see in self-driving and Shinkansen later. This is what Chapter 3's "coders go away, builders remain" means: coding gets complete replacement; builder work gets productivity gain — both happen inside the same field at once.

A warning here: now that coding is fully replaced, the importance of the requirements side actually rises. Skimp on requirements, and AI only mass-produces "commonplace code" that does not address the specific business problem. AI is excellent at probabilistically reproducing what it has seen in prior samples from the same domain, but pinning down "the non-negotiable conditions of this organization's particular business" can only be done by the human writing the requirements.

The faster AI gets, the faster and larger the cost of sloppy requirements piles up — a vast amount of "runs but ordinary" code gets produced and maintenance collapses (the same vibe-coding failure mode from Chapter 2, now faster and at greater volume). In a world where coding is cheap, requirements are what determine a software system's differentiation and lifespan.

Other AI applications stall at the last 1%

In the reverse — domains where the rules are not explicit, or correctness is hard to verify — AI does not advance at the same speed. Missing either condition is enough to leave a stubborn last 1%. Three representative domains:

Look at rail — especially Japan's Shinkansen, where route and obstacles are tightly controlled — a closed system. Almost all normal operation can be automated. The rules are explicit; correctness in normal operation is easy to verify. But the judgment for accidents and equipment failures — derailment, defective equipment, natural disasters — is the kind of problem that cannot be enumerated at design time. It still falls to humans. The last 1% sits not in the system's openness, but in the unpredictability of abnormal events — no matter how closed the system, that part does not disappear.

This "judgment in abnormal events" is structurally hard for two reasons:

Because (1) and (2) compound, complete replacement in the physical world — even in a closed system — stays structurally hard.

In these domains, AI delivers enormous value as a productivity tool — document drafts, driver assistance, routine work by collaborative robots. But complete replacement does not happen. There is a deep valley between "can do 99%" and "can do 100%."

The IT industry's AI narrative often overlooks — or pretends not to see — this 99/100 valley. Every time AI comes up, lines like "solves labor shortages across every industry" and "all white-collar work gets automated" surface. That is overestimation.

This sub-series stands apart from that overestimation. We argue complete replacement only for one specific area — "coding" inside software development — where the rules are explicit and correctness is mechanically verifiable. We do not claim the same complete replacement at the same speed in the rest of software development or in other domains.

There is a deep valley between "can do 99%" and "can do 100%." "Coding" inside software development is the area that has crossed that valley. Most other areas (including the rest of software development) have not.

The writing of this article is itself the example

Living evidence of this claim sits in the writing process of this sub-series itself.

As Chapter 4 noted, this sub-series was written by one person plus AI in about a week. But that week included a long list of human corrections:

All of these are corrections produced by a human reading the AI's draft and judging. AI alone lets factual errors, slanted arguments, and tonal slips — exactly the kind of problems that cost a reader's trust — pass through. The level of this sub-series required human judgment, in every loop.

In other words, the writing process of this sub-series carried the same structure as desk work, self-driving, and robotics — AI writes most of the draft; the human holds judgment and correction. Productivity multiplies several times, but complete replacement does not happen.

"Coding is complete replacement; writing is productivity gain" — the claim of this sub-series and the writing process of this sub-series line up in the same structure.

The five-year horizon

The "few years" of this sub-series — fix the concrete time scale here. The main changes complete in about five years — that is the outlook of this book.

Why five? Several independent time scales converge in that band:

The band where these overlap is roughly five years. Not so slow that it deserves "ten years," not so fast that it deserves "one to two." The main changes complete in about five years — that is the concrete time-scale outlook.

But "five years" refers only to the main changes, not everything. Core-system replacement in regulated industries takes longer. Some areas will still hold old models after ten years. Even so, the mainstream of the industry moves to AI-native within about five years.

The transition is irreversible

Finally, confirm the irreversibility of the change.

Each piece moves only in one direction. So the chain as a whole moves in one direction. Once the chain starts, no structural force exists that stops it.

One historical comparison to keep in view. The invention of the printing press in the 1450s reshaped the structures of the church, the university, and the state over two hundred years — preparing the ground for the Reformation, the scientific revolution, and the modern nation-state itself. The LLM holds incomparably greater intensity. What the printing press democratized was reading (access to existing knowledge); what the LLM democratizes is making (knowledge generation, judgment, implementation). There is no wall of literacy to clear first; natural language works for anyone. The speed of diffusion is on a different order — what took the printing press decades, the AI era achieves in years. Read against this difference in intensity, the five-year horizon this sub-series draws is, if anything, a conservative estimate.

The change completing in five years is irreversible. It is driven by one-way forces only, so a rewind cannot happen structurally.

The free person of the Middle Ages, and the free person of the AI era

When the medieval European "free person" emerged out from under feudal lords, four conditions came together at once. Economic autonomy (the free farmer who tilled his own land, the urban citizen, merchant, and craftsman who traded independently), political self-governance (the free cities that won their charters from lords), the means of touching reality (the right to bear arms, the capacity to grow one's own crops), and education — the seven liberal arts.

The conditions that converge as the AI-era "free person" — the builder of this sub-series — stands up correspond one-to-one.

Dimension Medieval freedom AI-era freedom
Economic autonomy One's own land, independent trade Building one's own back office and software with a few-thousand-yen-a-month AI; exiting SaaS and SIer dependence
Political self-governance Free cities that wrested charters from lords Holding one's own data, judgment, and systems on one's own machine; exit from cloud-vendor dependence
Means of touching reality Bearing arms, growing one's own food Local LLMs, open source, one's own server; infrastructure that keeps running through blackouts and network outages
Education The seven liberal arts The contemporary liberal arts — judgment, verbalization, logic, systems thinking, ethics (Chapter 4)

Just as the medieval liberal arts could not stand on education alone, the contemporary liberal arts cannot stand by themselves either. A free person comes into being only when all four converge. And just as the free citizens of medieval cities formed guilds to strengthen their economic and political weight, the AI-era builders will move, as a profession that sells judgment, toward bar-association– and medical-society–like guilds of their own (Chapter 9).

Employment is the AI era's serfdom — the rise of self-employment is structural

Placed next to the "medieval free person," one more thing becomes visible — modern employment (the salaried worker) sits, structurally, in the same position as the medieval serf.

Dimension Medieval serf Modern employee
Ownership of the means of production Lord's land and tools Employer's office, equipment, IP, data, infrastructure
Self-determination of labor Cultivating at the lord's direction Working at the supervisor's direction
Freedom of movement Tied to the land Tied by employment contract, mortgage, in-company career
Income predictability Stable under the lord's protection Trading freedom for salary stability
Locus of judgment The lord The employer
What is received in exchange Food and protection Salary and benefits

The "stability of employment" and the "stability of serfdom" are the same trade-off, structurally — handing over the right of self-determination in exchange for predictability of survival. This is not a claim of moral equivalence (modern employment has legal protections and contractual freedom). It is an analytical observation that on the three axes of ownership, judgment, and mobility, the structure matches.

And the reasons employment stops fitting in the AI era are structurally clear:

  1. The means of production are now individually ownable — a few-thousand-yen-a-month AI, local LLMs, open source, one's own server. The employer no longer needs to monopolize them.
  2. One person + AI = a ten-person team (Chapter 4) — the payoff of concentration disappears.
  3. The boundary between judgment and execution closes within one person (Chapter 4) — the overhead of aggregation, coordination, and management becomes pure waste.
  4. Judgment-centered professions are intrinsically inclined to independence — lawyers, doctors, accountants prefer solo practice and partnerships not by accident (Chapter 9).

The rise of self-employment is not a policy or lifestyle question. It is structural necessity. The same structure under which medieval free citizens, free farmers, and craftsmen were all "self-employed" returns in the AI era.

Employment is the contemporary form of medieval serfdom. Self-employment is the contemporary form of being a free person.

The structural changes this sub-series has been arguing — the SIer commission model's structural uneconomy (Chapter 6), customers building for themselves (Chapter 5), the judgment-centered builder (Chapters 4 and 9), the error of the "specialized engineer" advice (this chapter) — all converge on one point: the industry structure organized around employment is reshaped in the AI era.

The middle layer — builders who hold physical reality

Between the pure-software free person (the builder of this sub-series) and the pure-physical free person (of the natural- farming series), a middle layer that bridges the two rises up.

The medieval world had the same layer — the stonemasons, carpenters, smiths, weavers. They held guilds, had work in both city and countryside, and kept a foot in both the city's self-governance and the soil's reality. It was precisely this craft layer that accumulated the technical capital the Renaissance was built on.

The middle layer of the AI era sits in the same structural place — inputs from physical reality (sensors, observation, material), outputs in physical reality (objects, harvests, repaired machines, buildings), with AI as the mediator doing the design and analysis, while the hand that touches reality remains a human hand. Who belongs here:

Chapter 9's "maker types and field technicians enter embedded" was precisely about new entry into this middle layer. The labor demand created by "physical goods become scarcer" (Chapter 10) will be absorbed here too — the coders flowing out of the SIer industry won't all rejoin pure software; a path sideways into the middle layer opens here as well.

The middle layer is the contemporary form of those who gain power by touching reality. The strongest form of the AI-era free person appears here.

Japan, with deep manufacturing, town-factory, natural-farming, electronics-tinkering, and repair-culture foundations, holds a structural advantage in the move to this layer. As the alternative path to the "become a specialized engineer" advice in the next section, this gives us a second route alongside "sideways onto the liberal arts": "sideways into builders who hold physical reality." Both are roads out of the lord's manor.

"Become a specialized engineer" misreads the structure

There is a widely circulated piece of advice — "in the AI era, become a specialized engineer, hold a deep specialty AI cannot take, like security or ML." It misreads the structure.

What AI is absorbing is the whole layer of software engineering, not a particular subdomain inside it (Chapters 1 and 3). Going deeper into a specialty only shifts the date by which the specialty itself is overtaken — the underlying structure does not change. The medieval analogue would be telling a serf, "become a more specialized serf and you will be free." Freedom does not come from going deeper into the specialty; it comes from stepping out of the lord's structure of control.

The path to becoming a "free person" of the AI era is the same. The right move is not to deepen within engineering. It is to step sideways onto the liberal-arts axis — judgment, verbalization, ethics, systems thinking. That is the structurally correct direction of motion.

The road to becoming a free person is not deeper specialization. It is stepping out of the lord's structure of control. The AI era is no different.

This is the beginning of the Second Renaissance

The structural change this sub-series has been tracking — from coder to builder, from software engineering to the liberal arts, from employment to self-employment, from the lord's manor to the free city, from pure software to a middle layer that holds physical reality — lines up, item for item, with the structural change of the First Renaissance (14th–17th centuries).

Element First Renaissance Second Renaissance (AI era)
The classics being recovered Greek and Roman classical learning The liberal arts (Chapter 4)
The polymath ideal Leonardo da Vinci The builder, one person + AI (Chapter 4)
Individual subjectivity The humanist "I" One's own tools, one's own data, one's own judgment
Vernacular liberation Dante's Italian, Luther's German Natural language becomes "the programming language"
Free cities and guilds Florence, Venice, the craft guilds The AI-era free person, professional guilds (Chapter 9)
The accelerator The printing press (1450s) — democratizing reading The LLM — democratizing making (this chapter)
Reformation Religious decentralization (against the Roman church) Anti–vendor-concentration, anti–employment-centric, anti-SIer (this book)
The new rising class The bourgeoisie (commerce, banking, manufacturing) The AI-native builder, the self-employed judgment professional
New forms of art Perspective, anatomy, naturalism AI-assisted creation under human judgment

Nine items, all corresponding. This is not metaphor — it is structural similarity.

And just as the First Renaissance did not begin one morning — the self-governance of 12th–13th-century cities, the formation of the guilds, scholastic philosophy, and the rediscovery of classical texts through the Crusades accumulated as the underlying ground, which the printing press of the 1450s accelerated — the Second Renaissance is following the same pattern. The personal computer, the Web, open source, maker culture, the revival of natural and organic farming, the data-sovereignty movement, the AI ethics conversation have accumulated as the ground; the LLM (from 2022 onward) is now the accelerator.

The five-year structural transition this sub-series describes is one cross-section of the Second Renaissance. The sub-series covered the software domain, but the same structural change is proceeding in other domains of life at the same time.

The AI revolution is the completion of the IT revolution

Treating "the AI revolution" as a new, separate revolution is another misreading. The AI revolution is the completion of the IT revolution — seventy years of the IT revolution finally fulfilling its original promise.

The IT industry, until now, has had humans hand-writing the code that automates work. The original IT promise was "computers do the work, humans are freed." Yet for seventy years, the side that implements the automation has been doing it by hand — a strange structure. The consequences: programmer became one of the highest-paid professions; the cost of automation often exceeded the cost of doing the work manually; a massive industry of "manual labor for automation" emerged — SIers, consultancies, SaaS.

Logically odd. If automation is the goal, making the automation should also be automated. The LLM dissolves the twist by writing the code itself. The AI revolution is not the beginning of a new revolution; it is the completion of the IT revolution.

The completion functions as the strongest accelerator of the Second Renaissance. SIer contraction and the software-engineer → builder replacement are inevitable consequences, not sudden shocks.

The LLM is a powerful statistical-processing tool, not a superintelligence

Coolly viewed, the LLM (Claude, GPT, Gemini, etc.) is large-scale statistical processing of data — predicting the most probable next token in context. An overwhelmingly powerful tool, but it is not, in itself, "superintelligence."

The pitch that "AGI is coming, white-collar work will be fully automated in 12–18 months" (Suleyman/Microsoft AI) deliberately stages the LLM as a superintelligence parable to push "hand judgment over to AI" and "buy Copilot."

Structurally wrong: statistical-processing tools cannot bear judgment or responsibility. The LLM makes writing, looking up, organizing orders of magnitude faster, but deciding what to build, evaluating whether it is right, taking responsibility stay on the human side. This is the logical basis of the builder role.

Read the AI revolution as "the tool got strong, so the human role shifts to the judgment side" — simple, structurally clear, no need for AGI mysticism. The SIer contraction, the builder's rise, the foundational shift from software engineering to the liberal arts — all are explained by this simple structure.

The LLM is a powerful statistical-processing tool, not a superintelligence. Judgment and responsibility stay with the human — this is the logical ground beneath every argument in this sub-series.

Apps do not disappear, the way of making them does — app-making comes to resemble film-making

Stated precisely, the structural change is this: software development as an engineering craft disappears, but apps do not disappear.

The most precise analogy is film-making. A film is made by many independent specialist roles coming together (cinematography, editing, sound, lighting, costume, set design, VFX, scoring, acting). The audience is not aware of any of these. Only one artifact — the film — appears. At the center are not the people handling each technical task, but the director and the screenwriter — those who carry creative judgment.

App-making in the AI era takes on the same structure.

Film-making AI-era app-making
Director — overall vision and judgment Master builder / user — judging what to build
Script (manuscript) — natural language Natural-language source — what, for whom, how it behaves
Cinematography, editing, sound, VFX — specialist crew AI — picks up the engineering layer as a whole
Cast, set, costumes AI-generated UI, logic, data structures
The film (artifact) The app (artifact)

A director does not learn the camera. A screenwriter does not learn lighting. The audience does not know how the film was made. Even so, the film exists and carries value. App-making takes the same shape — the user does not learn engineering, AI picks up the engineering work, end users do not know how it was made; apps still exist.

Just as the printing press eliminated the scribe but not the book, the LLM shrinks the software engineer but not the app. Only the way of making changes — and the new way is closer to film-making than to book-printing.

Engineering-as-craft for software disappears; apps do not. App-making comes to resemble film-making — creative judgment at the center, with technical crew (= AI) gathered around it.

Film-making, however, has an enormous range. A Hollywood blockbuster still requires massive crews, hundreds of millions of dollars, and years of work, while a YouTube video can be made by one person with a smartphone in a few hours. AI-era apps will have the same range.

Scale Video production AI-era app-making Built by Trend
Monolithic large-scale Hollywood blockbuster SIer mega-project ERPs, monolithic core enterprise systems (formerly SIer) Declines — decomposed into mid-scale
Mid-scale Streaming series, theatrical film Focused systems, specialized SaaS, industry-wide systems Master builder Grows — more apps, fewer workers per app
Personal YouTube, TikTok Everyday personal tools The user Explodes

Monolithic large-scale is structurally a poor fit for the AI era — no single master builder can hold the whole, lock-in is created (Chapter 8), maintenance is intractable, the chain of judgment is dispersed. These systems are decomposed into combinations of mid-scale focused systems.

Mid-scale is the master builder's home territory — the scale at which the chain of judgment closes within one person (Chapter 4), the same position as lawyers and doctors (Chapter 9). Mid-scale apps themselves do not shrink — they grow: business apps that previously could not be cost-justified now get built in large numbers.

Personal is the user as director and crew.

What declines, then, is not the number of apps but the total number of workers building them (especially the monolithic SIer-project labor model). Apps themselves continue to exist across all three scales, and grow at mid-scale and personal.

This is the most precise statement of the structural change this sub-series has been arguing — the SIer labor model shrinks dramatically, master builders thrive at mid-scale as the directors of the AI era, and the personal scale is absorbed into the user.

Not only the AI revolution

We have been calling this "the AI era," but trying to capture the current structural change through AI alone misses half of it. The transitions running in parallel:

Just as the First Renaissance had to be understood as a composite of the printing press, the age of discovery, the Reformation, the scientific revolution, the rise of the nation-state, the rise of the commercial bourgeoisie, and the labor shifts after the Black Death, the Second Renaissance cannot be captured by the AI revolution alone. Multiple independent transitions converge; their convergence point is what makes "an era that is no longer the same." AI is the strongest accelerator among them, but not the cause of all.

An age of creation, and an age of upheaval

The Renaissance is in textbooks as a luminous age of creation — Leonardo, Michelangelo, Galileo, Gutenberg. The same age was also an age of violent upheaval: the Reformation and the wars of religion (the Thirty Years' War cut Central Europe's population by ~30%), papal corruption and schism, recurring plague, populist demagogues like Savonarola staging the "bonfire of the vanities" in Florence, strongman politicians like Cesare Borgia who became Machiavelli's model in The Prince. While the old order is collapsing and the new one has not yet stood up, people seek refuge in strong men and extreme words.

The Second Renaissance's upheaval side is already unfolding. Trump is the canonical figure — direct attack on the expert class, judiciary, scientific consensus; ad-hoc swings on tariffs, immigration, science budgets; streams of executive orders that override congressional checks; "I decide everything alone" governance.

Placed next to Nadella's Copilot strategy, the structure becomes visible. Nadella concentrates corporate judgment into a single AI; Trump concentrates national judgment into a single president. Different means, but both push the old era's logic of judgment-concentration to its absolute limit (see Microsoft's Nadella and Hegel's Philosophy).

Just as the Renaissance-era populist demagogues in the end disappeared, figures pushing judgment-concentration to the extreme will not fit the new structure (distribution, the free person, judgment held by the individual) and will exit. But the interim is turbulent — this too is the same pattern as the First Renaissance.

The Renaissance is an age of creation and an age of upheaval at the same time. Looking only at the creation side misreads the era. The upheaval side — Trump, Nadella, the runaway concentration of judgment — is also a symptom of the same transition. Both sides must be read together.

In closing

Compress the conclusion of the Software sub-series, all eleven chapters, into one passage here.

AI has reached human-top execution capability. This happened because the domain has explicit rules and verifiable correctness. As a consequence, the role called "coder" (the role centered on coding) goes away, and the builder (the judgment-side role) takes its place. The SIer commission model cannot structurally hold, and within roughly five years, the mainstream of the industry moves to AI-native in-house development — irreversibly.

But this is the story of one specific area: "coding" inside software development. The other parts of software development (requirements, design, operations, incident response, stakeholder coordination) carry the same structural 1% problem as self-driving and Shinkansen — this is where the builder remains. And the same speed of complete replacement is not claimed for other domains either (desk work, self-driving, robotics). In those, AI operates as a productivity tool — it does not reach complete replacement.

And during the same few years that AI advances, society as a whole moves toward physical goods becoming scarce (Chapter 10). AI data-center construction, manufacturing reshoring, the shift to natural farming — all generate physical-labor demand. Coders flowing out of the SIer industry are absorbed both inside and outside the industry.

What aiseed.dev has argued across the eleven chapters of this sub-series is:

A structural transition centered on "coding" inside software development completes in roughly five years. The transition is irreversible. And the conclusions from this specific area (= coding) must not be casually extended to the rest of software development or to other domains.

And the other current named in Chapter 4 — the foundational discipline of the technical profession shifts from software engineering to the liberal arts. Because what AI has taken is the core of software engineering (algorithms, languages, frameworks, design patterns), what remains on the human side is judgment — the craft of logic, verbalization, ethics, systems thinking, and history that the liberal arts have always been. The medieval artes liberales were defined as the arts of the free person — one who is not enslaved. The builder is the person who does not hand judgment over to AI — the contemporary form of that craft.

Hold those four, and the IT industry's AI narrative no longer sweeps you along. You can read what is actually happening, structurally, calmly. And from the position you stand in — customer commissioning software, coder, builder candidate, SIer executive — you can decide what to do over the next few years.

Thank you for reading to the end.

aiseed.dev will continue to publish articles that read the structure.


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