Developer Guide

Build resilient, maintainable automation systems.

This guide covers the design principles and implementation patterns that make automation reliable at scale. While the Operator Manual focuses on configuring and running systems, this guide focuses on building them well.

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Engineering Practices

Tactical patterns and strategic principles for automation engineering.

• Patterns

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  Concrete implementations with code examples.

  Implementation Patterns

• Principles

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  Decision-making frameworks and architectural guidance.

  Design Principles

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Patterns vs Principles

Aspect	Patterns	Principles
Level	Implementation	Architecture
Output	Code snippets	Decision trees
Question	"How do I...?"	"Should I...?"
Example	Upsert pattern in bash	When to fail fast vs degrade

Patterns are the how. Principles are the why and when.

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What's Covered

Patterns

• Idempotency - Make operations safe to retry
• Workflow Patterns - Structure scalable CI/CD workflows
• Caching - Avoid redundant work
• Work Avoidance - Skip unnecessary operations

Principles

• Graceful Degradation - Fail to safer states
• Fail Fast - Detect problems early
• Prerequisite Checks - Validate before executing

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Building automation that survives contact with production.