Byte-Sized Design

Byte-Sized Design

The Architect Is Not Being Replaced. The Architect Is Being Redefined.

And if you don't notice the difference, you'll end up on the wrong side of it.

Byte-Sized Design's avatar
Byte-Sized Design
Feb 17, 2026
∙ Paid

TLDR

Klarna went from 7,400 to 3,000 employees and called it AI. Then quietly started rehiring. Google’s engineers now review more than 30% AI-written code. Uber’s AI agents saved 21,000 developer hours — using a LangGraph-based system they call “Validator.” Entry-level programmer employment in the US fell 27.5% between 2023 and 2025.

The junior engineer is already being displaced. The mid-level engineer is next.

But the software architect? That role isn’t shrinking. It’s becoming the most important job in the building. The question is whether architects understand what it now actually requires.


The AI-replaces-engineers narrative is mostly wrong and also not entirely wrong. The nuance is where it gets interesting.

Klarna is the most cited example. In 2024, the company’s OpenAI-powered chatbot handled 2.3 million customer conversations in its first month. By late 2024, their headcount was down 40% from peak. CEO Sebastian Siemiatkowski went on CNBC and said the quiet part out loud: AI did this. Then, in 2025, he quietly started rehiring. “We went too far,” he admitted. Customer satisfaction had cratered. The AI couldn’t handle nuance, empathy, or edge cases. The humans they’d shed were carrying context the model couldn’t learn from a training set.

The Klarna story isn’t a win for the pro-AI camp or the anti-AI camp. It’s a case study in where the boundary actually is right now. Structured, repetitive, high-volume interactions? AI wins. Unstructured, novel, high-stakes decisions that require organizational and human context? Humans still win. Not comfortably. Not permanently. But for now, yes.

Software architecture sits at exactly that boundary. And that’s why the next few years will either be the best time in history to be a senior architect — or the last generation of architects who learned the craft before AI ate the curriculum.


What Uber Actually Proved

The most concrete AI-augmentation-in-engineering story from the last 12 months isn’t from an AI company. It’s from Uber.

Uber’s Developer Platform team built an internal AI agent called Validator using LangGraph, the graph-based orchestration framework that reached general availability in May 2025. Validator doesn’t make product decisions. It doesn’t design services. It catches bad code before it ships — running linting, checking build validity, surfacing test design issues, doing the kind of thankless hygiene work that junior engineers traditionally owned.

Then they built Autocover on top of it. Same architecture. Autocover generates test cases automatically using domain-specific expert agents. Engineers trigger it from inside their IDE. It streams context-aware tests in real time. For large files, the system executes up to 100 tests concurrently.

Result: 10% increase in test coverage across the Developer Platform. 21,000 developer hours saved.

That’s not a small number. That’s equivalent to roughly 10 full-time engineers doing a year of grunt work, automated.

But here’s the part that didn’t make the headline: Uber found that deterministic agents — rule-based, hand-coded logic — outperformed LLMs for tasks like linting and build execution. The LLM wasn’t the hero of every scene. The architecture was. Someone at Uber had to decide what gets an LLM node, what gets a deterministic function node, and how the graph flows between them. That person is an architect.


The Real Job Description Is Changing

User's avatar

Continue reading this post for free, courtesy of Byte-Sized Design.

Or purchase a paid subscription.
© 2026 Byte-Sized Design · Privacy ∙ Terms ∙ Collection notice
Start your SubstackGet the app
Substack is the home for great culture