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Product Engineering

52 results
Article ★ Featured

Database Schema Migration Strategies

Expand-contract pattern, zero-downtime migrations, and tooling.

database migration expand-contract zero downtime Flyway Liquibase
47 views May 24, 2026
Article ★ Featured

REST API Versioning Strategies

URL path, header, and query-param versioning compared with real-world tradeoffs.

API versioning REST URL versioning header versioning deprecation
51 views May 24, 2026
Article ★ Featured

REST API design principles we follow

Versioning, error formats, pagination, and auth patterns used across all Intersysop-built APIs.

API REST versioning auth JWT
44 views May 24, 2026
Article ★ Featured

JWT Authentication — Implementation and Security Patterns

Access tokens, refresh tokens, rotation, revocation, and common mistakes.

JWT authentication refresh token token rotation httpOnly
51 views May 24, 2026
Article ★ Featured

SQL Query Optimisation — Indexes, Execution Plans, and N+1

Practical techniques for making slow queries fast.

SQL query optimisation indexes N+1 EXPLAIN
45 views May 24, 2026
Article ★ Featured

Multi-Tenancy Patterns — Database-per-Tenant, Schema-per-Tenant, and Row-Level

Tradeoffs for SaaS data isolation, compliance, and operational complexity.

multi-tenancy SaaS database per tenant row-level security PostgreSQL
46 views May 23, 2026
Article ★ Featured

Observability — Logs, Metrics, and Traces

Implementing the three pillars with OpenTelemetry and making them actionable.

observability OpenTelemetry logging metrics tracing
47 views May 22, 2026
Article ★ Featured

Resilience Patterns — Circuit Breaker, Retry, Bulkhead, and Timeout

Prevent cascading failures with proven resilience patterns.

circuit breaker retry bulkhead timeout resilience
45 views May 21, 2026
Article ★ Featured

Progressive Delivery — Feature Flags, Canary, and Dark Launching

Techniques for releasing software confidently at any scale.

progressive delivery canary dark launch feature flags rollback
45 views May 20, 2026
Article ★ Featured

CI/CD Pipeline Design — From Commit to Production

Stages, gates, deployment strategies, and keeping pipelines fast.

CI/CD pipeline GitHub Actions blue-green canary
46 views May 19, 2026
Article ★ Featured

Secure Coding — OWASP Top 10 for Backend Engineers

Injection, broken auth, XSS, IDOR, and how to prevent each.

OWASP security SQL injection XSS IDOR
46 views May 19, 2026
Article

Event Sourcing and CQRS — Practical Implementation

Event store design, projection rebuilding, and operational realities.

event sourcing CQRS event store projection snapshot
45 views May 24, 2026
Article

Container Registry Management and Image Lifecycle

Tagging conventions, vulnerability scanning, retention policies, and registry options.

Docker container registry ECR Harbor image tagging
44 views May 24, 2026
Article

Service Mesh — Istio and Linkerd for Microservices

mTLS, traffic management, observability, and the operational cost of a service mesh.

service mesh Istio Linkerd mTLS sidecar
43 views May 24, 2026
Article

HTTP Caching Strategies for APIs and Web Applications

Cache-Control headers, ETags, CDN caching, and cache invalidation.

HTTP caching Cache-Control ETag CDN stale-while-revalidate
32 views May 24, 2026
Article

Implementing Rate Limiting in APIs

Token bucket, sliding window, fixed window — algorithms and implementation patterns.

rate limiting token bucket sliding window Redis API
39 views May 24, 2026
Article

Idiomatic REST API Design Patterns

Naming conventions, filtering, sorting, sparse fieldsets, and HATEOAS considerations.

REST API design naming conventions filtering sorting
49 views May 24, 2026
Article

Serverless Architecture — When Functions Work and When They Don't

Cold starts, event-driven patterns, cost model, and the right use cases.

serverless AWS Lambda cold start event-driven FaaS
46 views May 24, 2026
Article

OAuth 2.0 and OIDC — Implementing Secure Third-Party Auth

Authorization code flow, PKCE, scopes, and integrating with identity providers.

OAuth 2.0 OIDC PKCE authorization code Auth0
42 views May 24, 2026
Article

API Pagination — Cursor, Offset, and Keyset Patterns

When each method works, performance tradeoffs, and implementation details.

pagination cursor offset keyset API design
44 views May 24, 2026
Article

Designing and Publishing API Client SDKs

Auto-generation vs handwritten, retry logic, versioning, and developer experience.

SDK API client openapi-generator retry developer experience
42 views May 24, 2026
Article

API Gateway — Responsibilities and Implementation Patterns

Authentication, rate limiting, routing, request aggregation, and when not to use a gateway.

API gateway Kong AWS API Gateway BFF rate limiting
47 views May 24, 2026
Article

API Idempotency — Safe Retries for Mutations

Idempotency keys, implementation, and which HTTP methods are idempotent by definition.

idempotency API Idempotency-Key POST retries
38 views May 24, 2026
Article

Message Queue Patterns — SQS, RabbitMQ, and Dead Letter Queues

Fan-out, work queues, priority queues, and poison message handling.

message queue SQS RabbitMQ DLQ fan-out
53 views May 24, 2026
Article

Dependency Management and Supply Chain Security

Lock files, vulnerability scanning, SBOM, and keeping dependencies up to date.

dependency management Dependabot Renovate SBOM supply chain
41 views May 24, 2026
Article

Docker Containerisation Best Practices

Writing efficient Dockerfiles, multi-stage builds, security hardening, and image size reduction.

Docker containers Dockerfile multi-stage build security
47 views May 24, 2026
Article

CDN and Edge Caching Strategy

Origin offload, cache key design, purging, and choosing a CDN.

CDN edge caching cache key purging Cloudflare
44 views May 23, 2026
Article

gRPC Service Design — Protocol Buffers and Production Patterns

Proto file design, streaming, deadlines, interceptors, and error handling.

gRPC Protocol Buffers proto3 streaming interceptors
46 views May 23, 2026
Article

Database Connection Patterns in PHP

PDO, prepared statements, connection pooling, and transaction management.

PHP PDO prepared statements transactions database
40 views May 23, 2026
Article

DORA Metrics — Measuring Engineering Delivery Performance

Deployment frequency, lead time, MTTR, and change failure rate in practice.

DORA metrics deployment frequency lead time MTTR change failure rate
44 views May 23, 2026
Article

Our observability stack for production services

Logs, metrics, traces — how we instrument every service we ship.

observability logging metrics traces OpenTelemetry
41 views May 22, 2026
Article

Feature Flags — Safe Deployment and Gradual Rollout

Types of flags, implementation patterns, and avoiding flag sprawl.

feature flags gradual rollout A/B testing LaunchDarkly Unleash
44 views May 21, 2026
Article

The Twelve-Factor App — Principles for Modern Services

How the twelve factors apply to real production services today.

twelve-factor twelve-factor app cloud native stateless config
46 views May 21, 2026
Article

Health Check Endpoints — Readiness, Liveness, and Startup

Implement correct health endpoints so orchestrators route traffic and restart containers appropriately.

health check liveness readiness Kubernetes load balancer
39 views May 21, 2026
Article

Kubernetes Deployment Patterns for Production Services

Deployments, Services, Ingress, HPA, and resource management.

Kubernetes K8s Deployment HPA readiness probe
46 views May 21, 2026
Article

Load Testing with k6

Script a realistic load test, interpret results, and find bottlenecks before they find users.

k6 load testing performance P95 P99
44 views May 21, 2026
Article

Background Job Queue Design

Idempotency, retries, dead letter queues, and job observability.

background jobs queue idempotency DLQ retry
45 views May 20, 2026
Article

GraphQL vs REST — When to Use Each

Comparing query flexibility, over-fetching, tooling, and operational complexity.

GraphQL REST API design DataLoader N+1
49 views May 20, 2026
Article

Database Connection Pooling — Why It Matters and How to Configure It

Pool sizing, connection lifetime, and debugging pool exhaustion.

connection pool database HikariCP PgBouncer pool sizing
43 views May 20, 2026
Article

API Testing Strategy — Unit, Integration, Contract, and E2E

Building a test pyramid that catches real bugs without slowing delivery.

API testing unit tests integration tests contract testing Pact
44 views May 20, 2026
Article

Extracting Microservices from a Monolith

The strangler fig pattern, identifying seams, and avoiding the distributed monolith.

microservices monolith strangler fig distributed system architecture
43 views May 19, 2026
Article

Designing a Reliable Webhook System

Delivery guarantees, signature verification, retry logic, and consumer best practices.

webhooks HMAC signature verification idempotency retry
36 views May 19, 2026
Article

Logging Best Practices for Production Services

Structured logging, log levels, correlation IDs, and log aggregation.

logging structured logs correlation ID log levels Loki
47 views May 19, 2026
Article

Distributed Tracing — Propagating Context Across Services

Trace context propagation, sampling strategies, and analysing traces.

distributed tracing OpenTelemetry trace context sampling Jaeger
48 views May 19, 2026
Article

OpenAPI Spec-First API Development

Write the contract before writing code — benefits, tooling, and workflow.

OpenAPI Swagger spec-first API design Spectral
44 views May 19, 2026
Article

API Error Handling — Consistent Error Responses

Error format standards, HTTP status code usage, and client-friendly error design.

API error handling HTTP status codes error format validation
34 views May 19, 2026
Article

Microservices Communication — Sync vs Async Patterns

REST, gRPC, message queues, and choosing the right pattern for each interaction.

microservices gRPC REST message queue Kafka
36 views May 19, 2026
Article

Async/Await Patterns and Common Pitfalls

Concurrency, parallelism, error handling, and avoiding common async bugs.

async/await JavaScript Node.js Promise concurrency
52 views May 19, 2026
Article

Semantic Versioning — MAJOR.MINOR.PATCH in Practice

When to bump each version number and how to communicate breaking changes.

semantic versioning semver breaking changes API versioning changelog
41 views May 19, 2026
Article

API Documentation Best Practices

What makes documentation useful, tooling, and keeping docs accurate.

API documentation OpenAPI Redoc Swagger developer experience
42 views May 18, 2026
Article

WebSockets — Building Real-Time Features

Connection lifecycle, heartbeats, reconnection logic, and scaling with Redis pub/sub.

WebSocket real-time Redis pub/sub heartbeat reconnection
43 views May 18, 2026
Article

Implementing Search — From Basic SQL to Elasticsearch

Full-text search progression from LIKE queries to dedicated search engines.

search full-text search Elasticsearch PostgreSQL vector search
43 views May 18, 2026