Mathias Paulenko
Software Engineer & Founder of StackPractices
Mathias Paulenko
Software Engineer
Software engineer with 12+ years of experience building production systems across Python, JavaScript, React, and DevOps. I have contributed to enterprise projects spanning CI/CD pipelines, API design, cloud infrastructure, and full-stack development.
StackPractices is my personal project, born from a simple belief: great documentation should be copy-paste ready. Every recipe, pattern, and guide on this site is designed to save you time and help you ship faster.
Published Works (984)
Date Formatting in Python, JavaScript & Java
How to parse, format, and display dates across timezones in Python, JavaScript, and Java, with a...
Secure APIs with HTTP Security Headers
How to configure essential security headers like HSTS, CSP, and X-Frame-Options to protect APIs and...
Event-Driven Serverless Functions: Lambda & EventBridge
How to design loosely coupled systems using serverless functions triggered by events from message...
Metrics Aggregation: Collect, Tag
How to collect, tag, and aggregate business metrics for observability. Covers Prometheus,...
Backend Engineer Onboarding Checklist
A thorough checklist for onboarding new backend engineers covering environment setup, codebase...
Penetration Test Report Template with Remediation
Document security assessment findings with this penetration test report template — risk ratings,...
NoSQL Database Selection — MongoDB, DynamoDB, Cassandra
A practical guide to choosing the right NoSQL database. Compare document, key-value, wide-column,...
Time-Series Databases — InfluxDB, TimescaleDB, ClickHouse
Practical guide to time-series databases: when to use a TSDB, data model, retention policies, and...
OpenTelemetry Guide: Traces, Metrics and Logs
A practical guide to OpenTelemetry in production: instrumentation, collectors, sampling strategies,...
Security Best Practices Guide
A thorough guide to application security: authentication, authorization, input validation, secrets...
Compress and Decompress Files with ZIP, GZIP, and TAR
Create and extract ZIP, GZIP, and TAR archives in Python, Node.js, Java, and Bash, with streaming...
Detect and Fix N+1 Queries in GraphQL Resolvers
Identify N+1 query problems in GraphQL resolvers using logging, DataLoader, and query analysis...
GraphQL Error Extension Pattern
Attach structured metadata to GraphQL errors using extension codes for predictable client-side...
Data Retention Policy Template
A template to define how long data is kept, when it is archived, and when it must be deleted for...
Accessibility Audit Checklist
A WCAG 2.2 compliance checklist covering perceivable, operable, understandable, and robust criteria...
Database Design Guide
A practical guide to designing relational databases with normalization, indexing, and relationship...
Build a WebSocket Server (Python, Node.js, Java)
How to build a WebSocket server for bidirectional real-time communication, with connection...
Generate XML Sitemaps Dynamically
Build and serve XML sitemaps from live application data — pagination past the 50k-URL limit,...
Practical Design Patterns Guide
Pick the right design pattern for each problem: Singleton, Factory, Observer, Strategy and more,...
Docker Compose: Multi-Service Local Development
Master Docker Compose for local development: multi-service environments, networking, volumes,...
Implement a GraphQL API
Build a production-ready GraphQL API with typed schemas, resolvers, and mutations in Python,...
JWT Authentication
Sign, verify, and refresh JWTs in Python, JavaScript, and Java — access/refresh flows, RS256 key...
Caching Strategies: Browser, CDN, Redis & Database
Implement effective caching at every layer of the stack: browser cache, CDN edge, Redis application...
Build Serverless Functions
Create and deploy serverless functions with AWS Lambda, Google Cloud Functions, and Azure Functions...