Quick reference
Developer cheat sheets
- Sheets
- 24
- Areas
- 6
- Download
- PNG and PDF
- Cost
- Free
Languages 2
Front end 3
- RX22 items
React
Components, props, state, effects and the hooks you use in nearly every React app.
Open the sheet - NX27 items
Next.js
The App Router files, server and client components, data, links, images and settings in Next.js.
Open the sheet - CSS35 items
CSS layout
Selectors, the box model, Flexbox, Grid, positioning and responsive rules in one place.
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Back end and data 8
- node26 items
Node.js
Run scripts, use modules, read files, build a small server and manage packages with npm.
Open the sheet - SQL27 items
SQL
Read, filter, group, join, change and design data with standard SQL.
Open the sheet - pg27 items
PostgreSQL
psql commands, handy types, JSON, upserts, query plans and backups for PostgreSQL.
Open the sheet - KV20 items
Redis and caching
Core Redis commands and the caching patterns, limits and problems you must know.
Open the sheet - HTTP29 items
HTTP
Methods, status codes, headers, cookies and a curl example for talking to any web server.
Open the sheet - API21 items
REST API design
Name resources, choose methods and codes, add paging and errors, and keep an API easy to use.
Open the sheet - QA24 items
Testing
The test types, the Arrange-Act-Assert pattern and the Jest and Vitest functions you reuse.
Open the sheet - SEC22 items
Web security
The common web attacks, a one-line defence for each, and the headers and habits that stop most of them.
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Tools 5
- git33 items
Git
The Git commands you use every day: save work, branch, merge, share and undo mistakes safely.
Open the sheet - $_39 items
Linux command line
Move around, handle files, read logs, check the system and connect to other machines from the terminal.
Open the sheet - sh27 items
Bash scripting
Variables, conditions, loops, functions and safe settings for writing shell scripts that you can trust.
Open the sheet - vim24 items
Vim
Enough Vim to open, edit, search, save and leave any file without panic, on any server.
Open the sheet - .*30 items
Regular expressions
The symbols of regular expressions with plain examples, and how to use them in JavaScript.
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Systems and cloud 5
- dock31 items
Docker
Build images, run and inspect containers, keep data, use Docker Compose and write a Dockerfile.
Open the sheet - K8s30 items
Kubernetes
The kubectl commands to see, change and debug a cluster, and what each core object is for.
Open the sheet - IP32 items
Networking
Layers, ports, TCP and UDP, DNS records, IP ranges and the commands to check a connection.
Open the sheet - CI26 items
CI/CD and GitHub Actions
Write a GitHub Actions workflow, keep secrets safe, and choose a deployment strategy.
Open the sheet - SD30 items
System design
Numbers to remember, scaling patterns, trade-offs and a step-by-step plan for design interviews.
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