Architecture Models Readable by Teams and Coding AI
C4 modelling with journeys, contracts, and MCP for coding AI
In plain English
Viaduct keeps software design diagrams, user journeys and contracts in one place that coding AI can read. Teams avoid stale diagrams. They pay a plan. The founder reports the revenue.
$500/mo operator-reported revenue (Indie Hackers product page, Oct 29, 2026)
Operator: Igor Golovko
A named, real operator ran this and shared results publicly. The figures are their own.
Not disclosed.
The tool stack
Payments
Anthropic API ↗LLM / agents
Next.js ↗Web app framework
Prices are the vendors' published list prices as researched in Oct 2026 and change often — always check the vendor's pricing page.
Step-by-step setup
- Ship an API or tool developers and agents call directly.
- Great docs, SDKs and MCP/CLI access.
- Usage-based or tiered pricing.
- Grow via developer communities and integrations.
What's automated vs. the human 15%
The machine does
- Core AI generation/analysis
- Billing and onboarding
You still do
- Product quality and support
- Distribution and marketing
- Compliance and edge cases
Overview
C4 modelling with journeys, contracts, and MCP for coding AI. I needed C4 models that don’t go stale: structure, journeys and contracts in one place — readable by the team and by coding agents.
Operator: Igor Golovko. Website: https://c4.quietgridlabs.com
Estimated split: about 85% of the work automated, 15% human.
Realistic income
The founder reports $500 per month in revenue on their Indie Hackers product page (checked Oct 29, 2026). This figure is self-reported and not verified by Stripe or any third party. This is one operator’s result, often after months or years of work, and doesn’t predict yours. Check the live source — numbers change.
Risks
- Platform dependency on upstream models/tools.
- Support burden from technical users.
- Startup cost and time to first dollar are not disclosed.
*Income figures are illustrative ranges based on public pricing and typical outcomes reported by practitioners, not guarantees. Most new online businesses earn little or nothing at first. Not financial, legal or tax advice.
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