DI strategy comparison: constructor, setter, service locator with evaluation matrix and anti-pattern detection.
Dependency injection is the most misunderstood pattern in software engineering. Most teams use it because 'best practices' say so, without understandi...
Immutable infra: blue-green deploy, rollback strategy, artifact management, drift detection policy.
Mutable infrastructure is the root cause of configuration drift—every emergency SSH fix creates a server that cannot be reproduced. Immutable infrastr...
Dead letter queue architecture: poison message handling, exponential backoff, consumer patterns, DLQ reprocessing.
Production message queues inevitably receive messages that cannot be processed. Without a dead letter queue (DLQ), these messages block the consumer, ...
Idempotency key pattern for safe POST retries: UUID-based, 24h window, concurrency-safe.
POST requests are not idempotent by default. Network timeout on checkout does not tell you whether the charge went through. Without idempotency keys, ...
Rate limiting strategy: token bucket, leaky bucket, sliding window with distributed considerations.
Design a rate limiting strategy for a distributed API. Every rate limiter choice is a tradeoff between accuracy, memory, and distributed coordination....
CI/CD pipeline optimization: build time decomposition, cache strategy, parallelization, trunk-based feedback.
A CI/CD pipeline that takes 45 minutes leaks developer velocity. Developers context-switch, start other work, and the feedback loop collapses. The goa...
Immutable event store architecture: event structure, projection rebuild, snapshots, concurrency, audit trail.
Event sourcing stores every state change as an immutable event. Current state is derived by replaying events. This gives you a complete audit trail, t...
Structured logging strategy: JSON event schema, level policy, cross-service correlation with requestId.
Logging is debugging in production when you cannot attach a debugger. Every log line must answer: what happened, when, where in the code, and what con...
SQL N+1 detection, composite/covering indexes, query rewrite, prioritized by user impact.
Most DB performance problems are too many queries, not slow queries. The N+1 problem alone causes more incidents than all slow-query optimization comb...
Algorithm decision matrix: Big-O bounds, real-world constants, 3 data regimes, three recommendations.
Do not pick the first algorithm that comes to mind. Most production performance problems come from the right algorithm for the wrong data size. This f...
Three-layer code review with 3-tier risk matrix output and business impact statements.
You are reviewing a pull request. Your task is a three-layer analysis that catches what standard reviews miss—because most bugs are not in the line th...
Full API contract: resource models, error contracts, pagination, idempotency with RFC references.
Design an API contract before writing implementation. The contract is the source of truth—client and server build independently against it. Every ambi...
Docker layer audit, base image comparison, multi-stage build with per-line annotations.
Every RUN instruction creates a permanent layer. Files deleted in later layers still occupy space in the layer that wrote them. This is why naive Dock...
Mutation-testing-inspired gap analysis: branch inventory, simulation, 3 critical tests.
A passing test suite tells you nothing about quality. It tells you the code behaves as expected—not that it behaves correctly under all conditions. Th...
Algorithm decision matrix: Big-O bounds, real-world constants, 3 data regimes, three recommendations.
Do not pick the first algorithm that comes to mind. Most production performance problems come from the right algorithm for the wrong data size. This f...
Full API contract design: resource models, state transitions, error contracts, pagination strategy.
Design a REST or GraphQL API for the described domain. For each endpoint: 1. RESOURCE MODEL — JSON schema with types, required vs optional, nullable ...