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Notes on building reliable software with AI in the loop.

What AI-Assisted Software Development Actually Changes

A first-hand analysis of how AI compresses execution time, shifts bottlenecks, and reshapes small-team software development.

2026-01-15

In late 2025, shortly after being laid off, I built and shipped a production-ready, full-stack mobile application in roughly ten days as a solo developer. The app—RallyHub—was not a toy prototype. It included authentication, backend persistence, mobile clients, real-world workflows, and was usable by actual users.

That experience led to a question I’ve continued to think about:

What exactly does AI-assisted software development change—and what does it not?

This article is an attempt to answer that question, grounded in concrete experience rather than abstraction or hype.


The Baseline: How This Would Normally Be Built

Before AI-assisted development became practical, delivering a product like RallyHub would typically involve a small cross-functional team:

  • Product manager to define scope and prioritize
  • Backend engineer to design schema, APIs, and access control
  • Frontend or mobile engineer(s) for UI and client logic
  • QA or test coverage added later
  • Infrastructure and deployment setup along the way

Even with a strong team, a realistic timeline for an MVP with similar scope would be 6–10 weeks, largely due to coordination, hand-offs, and iteration cycles.

This isn’t a criticism of teams—it’s a reflection of how much overhead exists once work is distributed.


The Experiment: Solo Developer + AI Agents

In my case, the structure was different.

  • I acted as product owner, designer, and final decision maker.
  • ChatGPT was used as a reasoning and design agent: discussing workflows, clarifying requirements, and generating structured prompts.
  • Coding agents (Codex, Claude Code, Gemini) handled implementation, test execution, refactoring, and investigation of existing code.
  • I reviewed changes primarily at the behavioral and semantic level, not line-by-line code.

This was not “prompt once and ship.” It was an iterative loop:

  1. Clarify intent and constraints
  2. Ask an agent to investigate or implement
  3. Review the resulting behavior
  4. Adjust design decisions
  5. Repeat

What changed was not the need for discipline, but the speed at which execution responded to decisions.


Where the Time Actually Went Away

1. Coordination Cost Collapsed

In a traditional team, much time is spent on:

  • Aligning on scope
  • Breaking work into tasks
  • Waiting on dependencies
  • Reviewing and merging changes

With AI agents, execution could be parallelized without coordination overhead. There were no hand-offs—only intent, execution, and validation.

This alone accounts for a significant portion of the time compression.


2. Boilerplate Became Effectively Free

Large parts of modern applications are structurally repetitive:

  • Auth flows
  • CRUD operations
  • Schema migrations
  • Client–server wiring
  • Platform-specific setup

AI agents handled most of this quickly and correctly. The cost was no longer writing the code, but deciding what should exist and why.


3. Debugging Shifted from Search to Judgment

AI was particularly effective at:

  • Explaining unfamiliar build errors
  • Navigating large codebases
  • Proposing fixes based on logs and stack traces

However, deciding whether a fix aligned with product intent remained a human task. AI reduced the mechanical burden of debugging, not the conceptual one.


What Did Not Get Faster

This is the part often missing from productivity narratives.

Design Clarity Did Not Improve Automatically

When I moved too quickly into implementation without fully clarifying workflows—especially around identity, guest users, or lifecycle transitions—I paid for it later in rework.

AI made it easy to build something that “kind of worked,” which delayed confronting ambiguity. In that sense, AI amplifies both good and bad decisions.


Cognitive Load Became the Bottleneck

The limiting factor was no longer typing or wiring systems together—it was:

  • Holding system invariants in my head
  • Sequencing decisions correctly
  • Avoiding context switching across partially resolved problems

AI increased throughput, but it also increased the cost of unclear thinking.


A More Honest Comparison

It would be misleading to say:

“AI makes one developer 10× more productive.”

A more accurate statement is:

AI-assisted development allows a single experienced developer to achieve the output of a small team for well-bounded product scopes—by collapsing coordination and execution costs.

This only holds when:

  • Scope is clear
  • The developer has strong judgment
  • Infrastructure is managed
  • The product does not require heavy cross-organizational alignment

These are important constraints, and ignoring them leads to unrealistic expectations.


Implications for Teams and Roles

Smaller Teams Become More Viable

For early-stage products or internal tools, AI-augmented solo or very small teams can now deliver credible systems quickly. This shifts the calculus of experimentation.


Judgment Becomes More Valuable, Not Less

As implementation becomes cheaper, the value of:

  • Clear problem framing
  • Lifecycle thinking
  • Domain understanding
  • Decision sequencing

goes up, not down.

This has implications for engineering managers, technical PMs, and senior engineers: the role shifts away from coordination and toward clarity ownership.


Not Everything Should Be Built This Way

Large, regulated, or safety-critical systems still require rigor, redundancy, and institutional processes. AI does not remove the need for these—it simply changes where effort is spent.


Closing Thoughts

Building RallyHub with AI assistance didn’t make software development trivial. It made it more honest.

Execution responded immediately to decisions, which meant every unclear assumption surfaced quickly. That experience reinforced a lesson I’ve seen repeatedly across projects, both before and after AI:

Tools change. Responsibility does not.

AI compresses time. It does not compress judgment.


Further Reading

  • How I Built a Full-Stack Mobile App in 10 Days After Being Laid Off (LinkedIn)
  • RallyHub MVP Case Study
  • RallyHub Event Management (Flagship Case Study)

If you’re exploring how AI changes software development in practice—beyond demos and hype—I’m always open to thoughtful conversations.