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Clément Janssens

Building AI developer tools independently — infrastructure for the agent era as a solo technical founder.

Developer ToolsInfrastructureOpen SourceAI Agents

Company

Rerun — Agent Infrastructure

Founder Type

Developer / Technical Builder

Stage

Launch / Early Adoption

Region

Europe

AI Native Score

4/5

Founder Story

From Developer to Infrastructure Builder

Based on available information, Clément identified a gap in the AI agent ecosystem that many builders were overlooking: the infrastructure layer. While everyone rushed to build AI agents, few were thinking about the tools developers needed to build, test, and deploy those agents at scale.

His answer was Rerun — an infrastructure platform designed specifically for the AI agent era. As a solo founder, Clément didn't try to build everything. Instead, he focused on the critical pain points he'd experienced himself as a developer working with AI systems: observability, debugging, and workflow orchestration.

Focused infrastructure can unlock an entire generation of builders. The right tool at the right abstraction level doesn't just make development faster — it makes entirely new categories of products possible.

Why Infrastructure, Why Now?

Clément identified three converging trends that made agent infrastructure an ideal solo founder opportunity:

  1. Agent Explosion: Thousands of developers are building AI agents, but the tooling is fragmented and immature. Every team is reinventing the same infrastructure.
  2. Rising Complexity: As agents move from demos to production, the debugging, monitoring, and reliability challenges multiply — creating demand for purpose-built tools.
  3. Infrastructure as Leverage: Building infrastructure, rather than applications, means each customer's success with Rerun creates network effects — better tooling attracts more developers, which improves the tooling.

AI Workflow: How Clément Uses AI

As a solo founder building developer tools, Clément's AI usage spans the full product development lifecycle:

Key Insight: Build for Builders

Developer tools have unique advantages for solo founders: the users are developers, so they understand technical tradeoffs; distribution happens through GitHub and developer communities; and the feedback loop is fast because users can articulate exactly what they need.

Business Model & Distribution

Open Source First

Like many successful developer tool companies (Supabase, Vercel, PostHog), Rerun follows an open-source-first approach:

This model is particularly effective for solo founders because it converts code into marketing. Every GitHub star, every npm install, every community contribution expands reach without a marketing budget.

Lessons for Solo Founders

1. Pick Infrastructure Over Applications

Application markets are crowded and trend-driven. Infrastructure has slower initial adoption but creates durable competitive advantages. Once developers integrate Rerun into their workflow, switching costs are high — creating a natural moat.

2. Target Developers, Not Consumers

Developer tools have the best unit economics for solo founders: low support burden (users debug their own issues), community-driven distribution, and pricing power (businesses pay for tools that save engineering time).

3. Start Narrow, Then Expand

Clément didn't try to build the entire agent infrastructure stack. He focused on one pain point — observability — deeply, then expanded into adjacent needs. This "wedge" strategy is how most successful infrastructure companies start.

4. The Solo Advantage in Developer Tools

Unlike enterprise SaaS, developer tools benefit from a single coherent vision. A solo founder can make architectural decisions faster, maintain consistency across the codebase, and iterate based on direct developer feedback — advantages that larger teams struggle to match.

Sources & Verification

Sources used for this profile:

Information is compiled from publicly available sources and direct founder interactions where available. Profiles may be updated as new information becomes available.

Last updated: August 2026

What's Next for Rerun?

Clément is expanding Rerun's capabilities to cover the full agent development lifecycle — from prototyping to production monitoring. The platform is gaining traction in the open-source AI community, and early adopters are building increasingly sophisticated agent systems on top of the infrastructure.

His journey reinforces a pattern we see across AI Startup of One: solo founders who combine deep domain expertise with AI leverage are building infrastructure that will power the next generation of AI applications.