8 engineering stories
Case studies
See how real systems scaled, why they failed, and what changed afterward. Learn from decisions made under real constraints.
Engineering stories
8 case studies
Moving billions of messages from MongoDB to Cassandra
How Discord escaped MongoDB tail-latency degradation by rethinking their message data model around Cassandra partition semantics.
Discord · 2017 · migrationFrom fanout-on-write to hybrid delivery
How Twitter's news feed moved away from pre-computing timelines for all followers as accounts reached millions of followers.
Twitter · 2013 · scaleThe BGP leak that took down Cloudflare
How a single misconfigured route advertisement propagated globally and what Cloudflare changed about their route filtering and BGP safety nets.
Cloudflare · 2019 · outageThe Slack message storm incident
How a feedback loop between presence updates and reconnecting clients took down Slack and what changes in their notification and connection handling prevented recurrence.
Slack · 2015 · outageBuilding resilience with Chaos Monkey
How Netflix made reliability a continuous practice by deliberately injecting failures into production, and what this revealed about their dependency assumptions.
Netflix · 2011 · reliabilityThe Pods architecture: sharding by tenant
How Shopify decomposed a single Rails monolith into isolated per-merchant shards to achieve independent failure domains and predictable tenant resource limits.
Shopify · 2018 · architectureSharding GitHub's MySQL infrastructure
How GitHub moved from a single MySQL primary to a sharded topology to handle write throughput at scale while keeping query patterns compatible.
GitHub · 2016 · migrationJeff Bezos's API mandate and the SOA migration
How Amazon's internal mandate that all teams expose data only through service interfaces reshaped their monolith into an ecosystem of independent services.
Amazon · 2002 · architecture