Dev builds a tiny DNS resolver in C to show how simple DNS is at the packet level
cneuralnetwork · x · 2026-10-22
@cneuralnetwork wrote a minimal DNS resolver in C from scratch to understand what really happens when you type a URL into a browser. A terminal screenshot shows a UDP query to 1.1.1.1:53 (32-byte query, 160-byte response) resolving www.google.com into 8 A records with IPs and TTLs.
His takeaway: DNS is a surprisingly simple protocol at the packet level — encode a name, build a query, send over UDP, parse the answer, extract the IP. He plans to implement more networking protocols from scratch in C.
Related event: Developer Builds a Mini DNS Resolver in C to Explain Domain Resolution(3 posts)→
More from coding & agent
- One-shot RL repro: training Qwen3.5-4B to paint watercolour flowers with a judge model — charles_irl · 2026-10-22
- Open-source Claude Duet alternative Open-Duet hits 5.9k stars on launch day — matchaman11 · 2026-10-22
- LGWM: A World Model That Verifies GUI Agent Transitions and Detects Hijacked Screens — Jiaming Zhang · 2026-10-22
- Tracing AI agents with OpenTelemetry: costs, P95 latency, and gaps in one pipeline — silksong_when · 2026-10-22
- New pattern: sync X bookmark folders to agents for intent-driven auto-pilot jobs — vincent_koc · 2026-10-22
- Towards AI builds writing benchmark: 4 LLM judges, 1000 human A/B tests on AI slop — AI Engineer · 2026-10-22