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 (1032)
Create Objects Flexibly with the Factory Pattern
How to use factory methods, abstract factories, and dependency injection containers to decouple object creation from usage and improve...
Build Maintainable Applications with Hexagonal Architecture
How to structure applications using ports and adapters to isolate business logic from frameworks, databases, and external services for...
Implement Reactive Systems with the Observer Pattern
How to build event-driven, reactive systems using the observer pattern with pub/sub, event emitters, and reactive streams in JavaScript,...
Ensure a Single Instance with the Singleton Pattern
How to guarantee exactly one instance of a class exists in an application using lazy initialization, thread-safe creation, and...
Swap Algorithms at Runtime with the Strategy Pattern
How to encapsulate interchangeable algorithms and behaviors using the strategy pattern with dependency injection, function pointers, and...
Compress and Decompress Files with Gzip and Brotli
How to reduce file sizes for APIs, static assets, and log files using Gzip, Brotli, and zlib with streaming compression, content...
Implement Encryption at Rest for Databases and File Storage
How to encrypt sensitive data before storing it in databases, object storage, and backups using AES-256-GCM, envelope encryption, and key...
Minimize Cold Start Latency in Serverless Functions
How to reduce cold start times in AWS Lambda, Azure Functions, and Cloud Run using provisioned concurrency, lazy loading, runtime tuning,...
Design Effective Integration Tests for Reliable Systems
How to write integration tests that verify component interactions using test containers, API contracts, consumer-driven contracts, and...
Build Autonomous AI Agents with Tool Use and Reasoning
How to design AI agents that autonomously plan, execute tools, and iterate toward goals using ReAct, function calling, and memory...
Apply Prompt Engineering: What Works
How to write useful prompts for LLMs using role assignment, few-shot examples, chain-of-thought reasoning, and structured output formatting.
Call a REST API
How to make HTTP requests to a REST API and handle the JSON response in multiple languages.
Implement a gRPC API with Protocol Buffers
How to implement a gRPC API using Protocol Buffers for high-performance service-to-service communication
Password Hashing
How to securely hash and verify passwords using modern algorithms across Python, JavaScript, and Java.
Implement Secure Session Management
How to create, validate, and expire user sessions securely across web applications using cookies, tokens, and server-side storage.
Validate and Sanitize User Input Data
How to validate, sanitize, and constrain user input data at the application boundary using schemas, type checking, and validation libraries.
Manage Database Migrations Safely
How to version, apply, and rollback database schema changes using migration tools like Flyway, Alembic, and Liquibase in production...
Create and Use Database Views and Materialized Views
How to create and use database views and materialized views to simplify queries and improve read performance
Implement Optimistic Locking with Versioning
How to implement optimistic locking with versioning to prevent lost updates in concurrent database access
Environment Variables
How to read, set, and manage environment variables securely across Python, JavaScript, and Java.
GitHub Actions CI/CD
How to build and deploy with GitHub Actions using workflows, matrices, caching, and secrets.
Implement Graceful Shutdown and Zero-Downtime Restarts
How to implement graceful shutdown and zero-downtime restarts for web servers, workers, and containers
Set Up Pre-Commit Hooks
How to set up pre-commit hooks with husky, lint-staged, and pre-commit to enforce code quality before commits
Manage Application Secrets Securely
How to store, rotate, and inject API keys, database passwords, and certificates without hardcoding them in source code or environment files.