Example · explanation · question
Boundary tests in Java: why a passing test is not enough
A small function, two cases and a bug that a green test can miss.
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Programming and application operations: practical problems, code examples and design decisions.
Read, test the code and explore terms without leaving the article. Open glossary →
Java
TypeScript / Node.js
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TypeScript Strategy: two algorithms, one client
Understand Strategy with a short function. See when passing an algorithm helps and when an extra abstraction is unnecessary.
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Python: zero does not mean missing data
Distinguish a missing field, zero, None and an invalid type with a runnable API-rule example.
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PHP Adapter: change a provider format without changing the client
Separate an external provider’s data format from application code: money conversion, adapter responsibilities and common mistakes.
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A timeout after the write: retry without a duplicate effect
The response was lost, but the booking may exist. Explore idempotency keys, conflicting input and the limits of a small example.
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GitOps: Synced does not mean the application works
Three separate observations: configuration, resource health and the user operation.
Read articleAI in development
Example · explanation · question
An AI agent received an instruction. Is it allowed to act?
Separate a model proposal from tool permissions. A small testable example and the limits of data and environment protection.
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