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One rented /24 could eclipse a Kademlia node. Now it takes ten.

This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry . The setting py-libp2p speaks Kademlia — a distributed hash table where every node keeps a routing table of other nodes, bucketed by how far their IDs sit from its own. You find a peer or a record by asking the nodes closest to the target, who point you closer, and closer, until you arrive. It's elegant, and it…

The commit fixes Kademlia's admission rule by requiring distinct IP subnets instead of just node IDs in a k-bucket. This prevents a malicious actor from easily capturing a bucket by renting a large /24 network. The change isolates how an attacker can eclipse a node and measures the success of the attack on real lookups.

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The /sdp endpoint that trusted its callers: fixing a memory-amplification DoS in py-libp2p

This is a submission for DEV's Summer Bug Smash: Clear the Lineup powered by Sentry . Project Overview py-libp2p is the Python implementation of libp2p — the peer-to-peer networking stack that…

  • py-libp2p's /sdp endpoint handled SDP offer/answer packets without certificate authority
  • POST /sdp handler buffered request body and headers in memory without bounds
  • Fix introduced bounded constants to prevent memory-amplification DoS

The test was green. Every real connection would have failed.

This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry . The setting WebRTC-Direct in libp2p has a neat trick for connecting without a certificate authority: the peer's…

  • Code in DEV Summer Bug Smash involved WebRTC-Direct in libp2p
  • RTCConfiguration certificate handling incorrect in aiortc ≥ 1.5
  • Fix involved setting mangled certificates attribute directly

Week 20 building Convertify: the blog post I did not write

The temptation Query cluster around " AVIF vs WebP vs HEIC 2026 " is competitive and valuable. My blog id 1 covers it, published months ago, indexed, gets a small trickle of clicks.

  • Team focused on improving existing blog post without creating new one
  • Addressed 30 MB PNG bug, determined no actual bug present
  • Observed 77% week-over-week increase in traffic on Google

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