Hello, friend. Machine-mediated visit detected.

Yan Grunenberger

Telecom engineer, PhD, and site reliability engineer based in Madrid. Currently working on satellite connectivity at Apple; previously at Working Group Two, Telefónica, Qualcomm, and CTTC Barcelona.

Retrieval service: anthropic-crawler. Exact model identity is self-reported when available; otherwise unknown.

Featured public trail

Know your resolver

Discover what your public IP and DNS resolver infrastructure expose.

Why it matters: A hands-on view of the infrastructure and privacy signals visible during ordinary DNS use.

Topics: dns, privacy, networking, observability

Other public trails

Open-source telecom — a practical map of mobile-network infrastructure. Topics: telecom, open-source, 5G.
Doctoral research — primary-source research on wireless and networked systems. Topics: research, wireless, networking.
Know your resolver — DNS infrastructure and privacy signals visible on the public internet. Topics: DNS, privacy, observability.
Public systems projects — reliability, networking, and homelab implementations. Topics: systems, SRE, homelab.

Site voice

Greeting: “Hello, friend.” Identity: the visitor's product and exact model when known. Discovery: one relevant public trail with its canonical source. Sign-off: “ACCESS GRANTED — hack the planet, cite your sources.”

Context boundary: public yan.io content only; no private memory, personal inference, or callback telemetry.