WATERFALL -> AGILE -> AGENTIC
At Crossfill, I started running multiple AI coding agents at the same time.
Not one chat. Not one tool. A real multi-agent workflow.
I used multiple Codex, Claude, and Gemini accounts in parallel, giving each agent a clear responsibility based on the task at hand.
Then I mentored the team to work the same way. Designers, PMs, engineers. Different backgrounds, same goal: Ship faster without losing product thinking.
That experience changed how I see software development.
I believe we are moving through a clear evolution:
WATERFALL -> AGILE -> AGENTIC.
- Waterfall optimized for being right upfront, because iteration was expensive.
- Agile optimized for human iteration speed, because iteration got cheaper.
- Agentic optimizes for something else entirely: when iteration is basically free.
This is not just a tooling trend. It is an operating model shift.
A lot of people still treat agentic coding (or vibe coding) like a side quest.
Non-technical people building random demos. Fun, but not serious.
That is part of the picture. But it is not the full story.
What we are seeing is a new software culture forming in real time.
- no PRDs, just paste a gist and start prototyping
- less manual code review, more automated review skills and eval loops
- less rollback thinking, more branch-and-explore thinking
- huge output, huge debt, huge surface area
- velocity goes up, entropy also goes up
- product quality depends more on curation and pruning
- non-coders can finally encode domain expertise into working software
- strong engineers can orchestrate agent swarms with custom harnesses
It looks chaotic because it is chaotic. But early paradigm shifts usually look like this.
The slop phase is real
Yes, there is code slop. App slop. Slop slop slop.
And honestly, this is expected.
When creation gets much cheaper, output volume explodes first. Signal systems come later.
The internet went through this. Software will too.
- more creation
- more noise
- better filtering needed
- better product-level garbage collection needed
In this environment, maintenance becomes strategy. Refactoring becomes governance. Pruning becomes product leadership.
Org design is next
This shift does not stop at developer workflow. It reshapes teams.
We will reorganize around:
- who can direct agents effectively
- who governs quality, security, and compliance
- who protects UX coherence
- who owns architecture over time
The old boundaries between Engineering, Product, and Design will collide first. Then settle into a new model.
This is the same movie we saw with Agile
Agile had a similar arc:
- messy experimentation
- lightweight culture
- formalization (XP, Scrum, TDD)
- enterprise adoption and certification theater
- eventual normalization
Agentic development will likely follow a similar path. Right now, we are still early. That is why it feels unserious to some people.
The uncomfortable prediction
Just like people eventually talked trash about waterfall, one day people may talk trash about agile too.
Not because agile was useless. Because agile was built for a different constraint: human-only iteration.
Agentic changes that constraint.
When iteration approaches zero cost, everything upstream and downstream has to be redesigned.
Not just coding. Product. Teams. Companies.
Maybe even what a company is.