This Dev newsletter covers American Express’s cell-based payment system for high availability, a persistent agent memory layer on Elasticsearch, and a large-scale malware campaign on GitHub. It also highlights AI agent security roadmaps, GDPR consent fines, compiler reproducibility fixes, and new autonomous agent frameworks.

• A team built persistent agent memory by layering episodic/semantic/procedural Elasticsearch indices, hitting 0.89 recall with zero cross-tenant leaks
• Attackers flooded GitHub with 10,000 malicious repos hiding Trojans in ZIPs, constantly swapping readme links and commits to outpace detection
• Norway's DPA fined Elkjop €1.8 million for illegally forcing marketing consent as a condition of customer sign-up, a clear GDPR violation
• American Express uses a cell-based architecture where independent processing "cells" isolate failures so one crash doesn't cascade across the payments system