Most platform teams are building their IDP by composing tools they already trust. Backstage for the developer portal. Argo CD or Flux for GitOps. Prometheus and OpenTelemetry for observability. Cilium for network policy. KEDA for event-driven scaling.
That is not a workaround. That is the right instinct.
Every one of those tools is open source, CNCF-backed, and battle-tested across thousands of production environments. They succeeded because the code is auditable, the community compounds improvements faster than any single vendor can, and no one is locked into a roadmap they did not choose.
The pattern is consistent. The best infrastructure tooling of the last decade did not come from a closed product. It came from communities solving hard problems in the open and sharing the work.
The thing that does not get said enough
Teams building DIY platforms on these tools are doing impressive engineering. Composing Backstage, Argo, Flux, Prometheus, and KEDA into something cohesive requires real depth. The result fits your organization precisely because the people who built it understand your constraints.
That culture of building with open source rather than buying black boxes is how the best engineering orgs operate.
Where this is heading
As platform engineering matures, the next wave will be projects that compose this ecosystem into coherent, opinionated platforms without replacing any of it. Reference implementations that get the hard integration problems out of the way while keeping the modularity and the community trust.
Open source wins here too, because a platform your team can audit, extend, and contribute back to is one you can actually own long-term.
A project worth watching
OpenChoreo is a CNCF Sandbox project built entirely on this ecosystem. Backstage for the portal, Argo and Flux for GitOps, Cilium for network policy, OpenTelemetry and Prometheus for observability. The goal is not to replace these tools but to compose them into something production-ready from day one.
Worth a look if you are thinking about IDPs: <a href="https://openchoreo.dev/" target="_blank" rel="noopener nofollow">https://openchoreo.dev/</a> Architecture deep dive: <a href="https://openchoreo.dev/docs/overview/architecture" target="_blank" rel="noopener nofollow">https://openchoreo.dev/docs/overview/architecture</a> GitHub: <a href="https://github.com/openchoreo/openchoreo" target="_blank" rel="noopener nofollow">https://github.com/openchoreo/openchoreo</a>
What tools is your platform team currently composing? Curious what the community is gravitating toward.

🚀 Daily Open Source Tools Squad delivers daily articles, open-source projects, and technical resources for Developers & DevOps pros. Stay updated with the latest trends & insights!

📬 Join our mailing list! → theinfinity.dev

Daily Open Source Tools

Open source tooling is quietly dominating platform engineering, with teams composing CNCF-backed projects like Backstage, Argo CD, Flux, Prometheus, OpenTelemetry, Cilium, and KEDA into internal developer platforms (IDPs). The argument is that this approach wins because the code is auditable, community-driven improvements outpace vendor roadmaps, and teams avoid lock-in. The post predicts the next wave will be opinionated reference implementations that compose this ecosystem without replacing it. OpenChoreo, a CNCF Sandbox project, is highlighted as an example of this pattern — composing the same open source stack into a production-ready IDP.

Why open source is quietly winning platform engineering

In the cloud native era, adopting an open source architecture is a critical driver for long term scalability, agility, and innovation.