All Cheat Sheets
Dense one-page references with a gotcha for every entry. Seven new sheets, and links to the reference pages that were already on the site.
Seven New Sheets, Four Existing Ones
A cheat sheet here means one dense page of tables: the item, what it means in one line, and the gotcha that bites. Each new sheet ends with a "common mistakes" box and links to the long-form pages. The existing reference pages on the site are listed too, so there is one place to look.
Spring Annotations
Stereotypes, configuration, web, transactions, AOP, caching, security, testing and listeners, each with its gotcha.
SQL
Logical order of evaluation, joins, windows, CTEs, NULL logic, dates and the Oracle vs PostgreSQL differences.
Git
Everyday commands, branching, undoing, rebase vs merge, stash, bisect, worktree, config.
Docker & kubectl
docker run flags, build, compose, cleanup, and kubectl for reading, changing, debugging.
Kafka & RabbitMQ CLI
Kafka 4.0 tools, rabbitmqctl, diagnostics, rabbitmqadmin v2 and aws sqs.
Redis Commands
Commands by data type with complexity, TTL and eviction, persistence, cluster and redis-cli.
Big-O & Data Structures
Growth rates, structures, sorting, graph algorithms, Java collections and n limits.
Claude: Cheat Sheet and Finder
Goal-to-chapter finder, commands and file shapes you retype, surprises and a ledger of what was run.
Architecture: Reference & Glossary
Quick reference tables, glossary of terms, common misconceptions and resources.
System Design Reference & Resources
Patterns index, decision trees, key numbers and an interview guide.
Design Patterns: Reference Guides
Interviews, anti-patterns, pattern relationships and a Java standard-library map.
Every Sheet in One Table
| Sheet | What is in it | Link |
|---|---|---|
| Spring Annotations | About 130 annotations in eight groups plus a mistakes list | /cheat-sheets/spring-annotations/ |
| SQL | Evaluation order, joins, aggregates, windows, CTEs and sets, NULL logic, dates, Oracle vs PostgreSQL | /cheat-sheets/sql/ |
| Git | Commands in the four-places model, undo and history search, config and aliases | /cheat-sheets/git/ |
| Docker & kubectl | Container and cluster commands, pod status decoder | /cheat-sheets/docker-kubectl/ |
| Kafka & RabbitMQ CLI | Kafka 4.0 admin and console tools, RabbitMQ operator tools, SQS CLI | /cheat-sheets/kafka-rabbitmq-cli/ |
| Redis Commands | Per data type with the documented complexity, eviction, persistence, redis-cli | /cheat-sheets/redis-commands/ |
| Big-O & Data Structures | Complexity tables and Java collection facts | /cheat-sheets/big-o/ |
| Claude: Cheat Sheet and Finder | Claude Code commands, file shapes, surprises (existing page) | /claude/cheat-sheet/ |
| Architecture: Reference & Glossary | Quick reference tables and glossary (existing page) | /architecture/foundation/reference/ |
| System Design Reference & Resources | Patterns index, decision trees, key numbers (existing page) | /architecture/system-design/reference/ |
| Design Patterns: Reference Guides | Interview patterns, anti-patterns, relationships, Java stdlib map (existing page) | /tech/design-patterns/reference/ |
Find a Sheet by What You Are Doing
| Topic | Sheets | Related long-form pages |
|---|---|---|
| Java and Spring | Spring Annotations, Big-O (Java collections chapter) | Spring Guide, Java Collections |
| Databases and caching | SQL, Redis Commands | SQL Tutorial, Redis |
| Messaging | Kafka & RabbitMQ CLI | Messaging Map, Kafka Architecture |
| Delivery and operations | Git, Docker & kubectl | DevOps Map, Kubernetes Core |
| Algorithms and interviews | Big-O, Design Patterns Reference | DSA, Interview Patterns |
| Architecture and system design | Architecture Reference, System Design Reference | Architecture |
| AI-assisted development | Claude Cheat Sheet | Claude Guide |
Scan, Search, Print
These pages are meant to be scanned, not read top to bottom.
| Need | How |
|---|---|
| Find one item fast | Use the browser's find (Ctrl+F or Cmd+F) on the sheet: every command, flag and annotation is written in a code span, so searching for @Cacheable, --reset-offsets or ZADD lands on its row. |
| Jump between groups | The sticky bar under the page title lists the chapters of the sheet; each group is one chapter with one table. |
| Read the gotcha, not just the meaning | The last column of every table is the part that is easy to forget. If you only have a minute, read that column. |
| Go deeper | Each sheet ends with a "Go deeper" chapter linking to the long-form pages, and a "Version note" saying what was checked and where. |
| Print or save as PDF | Use the browser's print dialog. This site does not have a dedicated print stylesheet yet, so check the print preview first and print a single chapter if you want a one-page handout. |
| Keep a personal copy | Copy the table you use most into your own notes; tables paste cleanly into most editors. |
Every sheet has a Version note naming the version and source it was checked against, and says what could not be verified. Versions move: when your tool version differs, run the tool's own --help before copying a flag into automation.
How Each Sheet Is Built
| Element | Meaning |
|---|---|
| Table columns | Item, one-line meaning, gotcha (some sheets add complexity or a dialect column) |
| Code spans | Commands, flags and annotations exactly as typed |
| Common mistakes box | The failures that cost real time, as short rules |
| Go deeper | Links to the long-form page for each group |
| Version note | What was verified, against which docs or versions, and what was not |
- Meaning plus gotcha: a name alone is not enough; the gotcha column is the value.
- Verify against your version: tool behaviour changes (Kafka 4.0 removed
--zookeeper; Boot 3.4 deprecated@MockBean). - Short does not replace long: use the long-form pages to learn, the sheet to recall.