Research notes and article write-ups by Milan Niroula, a software engineer reading about AI, software engineering, design, how big tech solves problems at scale, and the inner life.https://mimi146.github.io/blog/enhttps://mimi146.github.io/blog/posts/context-engineering-for-ai-agents/https://mimi146.github.io/blog/posts/context-engineering-for-ai-agents/How to choose the goals, files, tool results, and notes a coding agent sees, and how stale or untrusted context makes it fail.Sun, 08 Nov 2026 00:00:00 GMTaiagentssoftware engineeringhttps://mimi146.github.io/blog/posts/spanner-truetime-external-consistency/https://mimi146.github.io/blog/posts/spanner-truetime-external-consistency/How Google Spanner orders transactions worldwide: TrueTime intervals, commit wait, Paxos groups, two-phase commit over Paxos, safe time and lock-free reads.Sun, 08 Nov 2026 00:00:00 GMTdistributed systemsdatabasesspannerconsistencypapershttps://mimi146.github.io/blog/posts/raft-understandable-consensus/https://mimi146.github.io/blog/posts/raft-understandable-consensus/How Raft keeps a replicated log consistent: terms, randomized elections, log matching, the Figure 8 commit rule, joint consensus, snapshots, linearizable reads.Sun, 01 Nov 2026 00:00:00 GMTdistributed systemsconsensusraftconsistencypapershttps://mimi146.github.io/blog/posts/10-backend-design-patterns-in-java/https://mimi146.github.io/blog/posts/10-backend-design-patterns-in-java/Repository, Factory, Singleton, Strategy, Observer, Builder, Adapter, Decorator, CQRS and Circuit Breaker in tested Java 21 and Spring Boot code, with pitfalls.Mon, 26 Oct 2026 00:00:00 GMTdesign patternsjavaspring bootbackendresilience4jcqrshttps://mimi146.github.io/blog/posts/dynamo-amazons-highly-available-key-value-store/https://mimi146.github.io/blog/posts/dynamo-amazons-highly-available-key-value-store/How Amazon's 2007 Dynamo kept carts writable: consistent hashing, sloppy quorums, hinted handoff, vector clocks, Merkle anti-entropy, and gossip (SOSP '07).Mon, 26 Oct 2026 00:00:00 GMTdistributed systemsamazonkey-value storeconsistencypapershttps://mimi146.github.io/blog/posts/tao-facebooks-social-graph-store/https://mimi146.github.io/blog/posts/tao-facebooks-social-graph-store/How Facebook's TAO served a billion graph reads/sec: objects & associations, leader/follower caches, refill messages, and master/slave regions (ATC '13).Sun, 18 Oct 2026 00:00:00 GMTdistributed systemsfacebookgraph storecachingconsistencypapershttps://mimi146.github.io/blog/posts/caching-spring-boot-redis-redistemplate/https://mimi146.github.io/blog/posts/caching-spring-boot-redis-redistemplate/How to integrate Redis as a caching layer in a Spring Boot application using RedisTemplate to reduce database load and response times, step by step with code.Wed, 14 Oct 2026 00:00:00 GMTspring bootrediscachingjavahttps://mimi146.github.io/blog/posts/scaling-memcache-at-facebook/https://mimi146.github.io/blog/posts/scaling-memcache-at-facebook/How Facebook scaled memcached to billions of requests per second: leases against thundering herds, Gutter pools, mcsqueal invalidation, and remote markers.Tue, 13 Oct 2026 00:00:00 GMTdistributed systemscachingmemcachedconsistencypapershttps://mimi146.github.io/blog/posts/scaling-slacks-job-queue/https://mimi146.github.io/blog/posts/scaling-slacks-job-queue/Slack put Kafka in front of Redis so enqueue stays up when workers stall: durable buffering, Kafkagate, JQRelay rate limits, and incremental migration.Sun, 04 Oct 2026 00:00:00 GMTdistributed systemsmessagingkafkaredisjob queueshttps://mimi146.github.io/blog/posts/how-discord-stores-trillions-of-messages/https://mimi146.github.io/blog/posts/how-discord-stores-trillions-of-messages/How Discord moved chat history from MongoDB to Cassandra to ScyllaDB: time-bucketed partitions, tombstone traps, hot partitions, and Rust request coalescing.Sat, 03 Oct 2026 00:00:00 GMTdistributed systemsdatabasesdata modelingsystems at scalehttps://mimi146.github.io/blog/posts/idempotency-keys-safe-retries/https://mimi146.github.io/blog/posts/idempotency-keys-safe-retries/Notes on how APIs like Stripe use idempotency keys so clients can retry failed requests without charging a customer twice, plus a minimal implementation.Sat, 03 Oct 2026 00:00:00 GMTsoftware engineeringdistributed systemsapi designsystems at scale