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 (1008)
API Performance Budget Template
A template for setting and tracking API latency and throughput performance budgets.
Async Task Cancellation Runbook — Python, JS, Go, Java
Runbook for cancelling long-running async tasks without leaks: cooperative signals, cleanup...
Architecture Decision Record (ADR) Template
A lightweight template for documenting major architectural decisions, their context, options...
Auto-Scaling Policy Template: HPA-Ready
Copy-ready auto-scaling policy template with scale-up/down thresholds, cooldowns, cost controls,...
Performance Budget Template
Template for defining and enforcing web performance budgets: LCP, INP, CLS targets, resource...
API Documentation Template
A reusable template for documenting REST and GraphQL APIs with endpoints, schemas, errors, and...
API Status Page Template for Incidents
A template for a public API status page that communicates uptime, incidents, and maintenance...
API Testing Strategy Template
A template for planning contract tests, integration tests, and load tests for APIs.
AWS Basics — Core Services for Developers
A practical guide to AWS core services for developers: compute, storage, databases, networking, and...
API Rate Limiting — Design Fair and Useful Throttling
A practical guide to API rate limiting: token bucket, leaky bucket, sliding window algorithms,...
Software Testing Strategy Guide
A practical guide to building a layered testing strategy with unit, integration, contract, 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...
AI Agents with Tool Use: ReAct in Practice
Build autonomous AI agents that can use external tools and APIs to accomplish complex tasks.
Coordinate Concurrent Tasks with Communicating
How to structure concurrent programs using channels, select statements, and goroutines for safe...
Ansible Playbook for Server Configuration
How to write and run Ansible playbooks for provisioning, configuring, and managing servers with...
JavaScript Drag and Drop File Upload with HTML5 API
Implement native HTML5 drag and drop file upload in JavaScript — drop zones, file validation,...
Integration Testing with Real Dependencies
How to test multiple components working together using real databases, HTTP clients, and message...
Agent Tool Selection Pattern: Fewer Tools, Better Calls
Dynamically select which tools an LLM agent can use based on the task context. Reduce token usage...
Embedding Cache Pattern
Cache LLM embeddings to reduce API calls and cost. Store embeddings with a content hash key and...
Anti-Corruption Layer: Isolate Legacy with Adapters
How to isolate legacy systems with translation adapters. Covers ACL facade, domain translation,...
Abstract Factory for Cross-Platform UI Component Families
Create families of related objects without specifying concrete classes, enabling platform-specific...
Abstract Factory Pattern
Create families of related objects without specifying concrete classes. A creational design pattern...
Actor Model Pattern: Concurrency Without Shared State
Isolate state in actors that communicate only via messages. Each actor processes one message at a...
Adapter Pattern for Integrating External REST APIs
Use the Adapter pattern to normalize responses from external REST APIs into a consistent internal...