Safe

Time Travel and Fail-Safe

How Snowflake preserves historical versions of data so you can query, clone, or restore it after accidental changes, and what happens after that window closes.

Operators and Truth in Groovy

Groovy's safe navigation, Elvis, and spaceship operators, operator overloading, and the rules of Groovy Truth for evaluating objects in boolean contexts.

Safe Calls and the Elvis Operator in Kotlin

The ?. safe call and ?: Elvis operator let you access members of nullable values and supply defaults without verbose null checks.

Hashes in Ruby

How Ruby's Hash class stores key-value pairs, including modern literal syntax, symbol keys, default values, and the Enumerable methods it inherits.

Kotlin Null Safety Cheat Sheet

Covers nullable types, the safe call and elvis operators, the not-null assertion, and platform types for handling null safely in Kotlin.

SQL Injection Prevention Cheat Sheet

Explains how SQL injection works and shows concrete, language-specific techniques to prevent it using parameterized queries and validation.

Cross-Site Scripting (XSS) Prevention Cheat Sheet

Covers the three main XSS variants and concrete output-encoding, sanitization, and CSP techniques to prevent script injection in web apps.