Programming Cheatsheets

C# Modern C# 14 syntax for strings, nullability, collections, LINQ, records, pattern matching, async code and generics. 4 sections · 40 commands C++ Compile and debug C++ with g++ and CMake, and use modern C++ (up to C++23): containers, algorithms, smart pointers, templates and threads. 6 sections · 54 commands CSS Layout with flexbox and grid, responsive design, custom properties, animations and modern selectors. 5 sections · 37 commands Go The go command for modules, building, testing and cross-compiling, plus the code patterns you write every day. 5 sections · 40 commands HTML HTML5 page structure, text, links, images, forms, tables and metadata, with accessible patterns. 5 sections · 35 commands Java, Maven and Gradle JDK commands to compile, run and diagnose Java programs, plus the Maven and Gradle commands for builds and tests. 4 sections · 42 commands JavaScript Modern JavaScript for arrays, strings, objects, async code, the DOM and modules, in copy-ready snippets. 6 sections · 54 commands Kotlin Kotlin syntax and idioms: null safety, data classes, collections, extension and scope functions, sealed types and coroutines. 5 sections · 30 commands PHP The php command line and the modern PHP 8 syntax you use every day: types, enums, match, PDO and more. 4 sections · 38 commands Python Run scripts, manage virtual environments and packages, and test and profile Python code. 4 sections · 26 commands Regular expressions Regex patterns for matching, grouping, lookarounds and common formats, plus how to use them in grep, sed, JavaScript and Python. 5 sections · 41 commands Ruby Run Ruby code, manage gems with Bundler, and use blocks, collections, classes, pattern matching and error handling. 4 sections · 30 commands Rust and Cargo Cargo and rustup commands for projects, dependencies, testing and releases, with the Rust patterns you reach for most. 5 sections · 40 commands SQL Everyday SQL for querying, joining, aggregating and changing data, with notes where PostgreSQL, MySQL and SQLite differ. 5 sections · 39 commands Swift Swift tooling and syntax: optionals, structs and enums, protocols, closures, error handling, async/await, actors and SwiftUI basics. 5 sections · 28 commands TypeScript Compiler commands, tsconfig options and the type patterns you use every day. 4 sections · 34 commands

.NET and ASP.NET Core The dotnet CLI for creating, building, testing and publishing projects, plus common ASP.NET Core and EF Core code. 6 sections · 37 commands Angular Angular CLI commands and standalone component, signals, template, routing, HTTP and forms snippets. 4 sections · 38 commands Astro Build fast content sites with Astro: components, layouts, routing, content collections, islands, endpoints and deployment. 4 sections · 23 commands Django Create projects, run migrations, test and deploy Django apps, plus the ORM queries you use every day. 6 sections · 38 commands Express Build HTTP servers and APIs with Express 5 on Node.js. 4 sections · 19 commands FastAPI Install, run, test and deploy FastAPI apps from the command line. 4 sections · 15 commands Flask Create, run, test and deploy Flask apps, with routes, templates, blueprints, sessions and database snippets. 5 sections · 33 commands LangChain Python snippets for LangChain 1: models, prompts, agents, tools, structured output, retrieval and tracing. 5 sections · 24 commands LangGraph Python snippets and CLI commands for LangGraph 1: state graphs, routing, memory, human approval, streaming and local dev. 6 sections · 31 commands Laravel Everyday Artisan commands for Laravel 13 projects. 5 sections · 25 commands NestJS Generate and run NestJS apps, and write controllers, providers, DTO validation, guards, interceptors, configuration and tests. 4 sections · 22 commands Next.js Create, run and build Next.js apps, and the App Router patterns you reach for most. 4 sections · 24 commands Ruby on Rails Create apps, generate code, manage the database and run tests with the Rails 8 command line. 6 sections · 44 commands Spring Boot Create, run, test, configure and package Spring Boot applications. 4 sections · 22 commands Svelte and SvelteKit Create Svelte 5 apps and write components with runes, template blocks, snippets and SvelteKit routes, loaders and forms. 4 sections · 29 commands Symfony Create apps, generate code, manage the database and debug with the Symfony CLI and console. 5 sections · 32 commands Tailwind CSS Install, build and configure Tailwind CSS 4 with the CLI, Vite or PostCSS. 3 sections · 14 commands Vue Create Vue 3 apps and write components with the Composition API and script setup. 4 sections · 22 commands

Hugging Face The hf command line, and Transformers and Datasets code for downloading, running, training and sharing models. 4 sections · 29 commands Matplotlib and seaborn Draw line, scatter, bar and histogram charts with Matplotlib, and statistical charts with seaborn. 4 sections · 29 commands pandas and NumPy Load, clean, reshape, group and analyze tabular data with pandas, and work with arrays in NumPy. 5 sections · 45 commands Polars Fast DataFrames in Python: expressions, filtering, grouping, joins, lazy queries and file formats. 3 sections · 23 commands Prisma ORM Model your database in a schema, run migrations, and query with the type-safe Prisma Client. Examples use the prisma-client-js generator; check the docs for newer generators. 3 sections · 27 commands PyTorch Tensors, autograd, models, training loops, saving and speed-ups in PyTorch 2. 4 sections · 24 commands React Hooks, components and patterns for React 19 in TypeScript or JavaScript. 5 sections · 23 commands scikit-learn Split data, preprocess features, train and evaluate models, tune hyperparameters and save pipelines with scikit-learn. 4 sections · 24 commands SQLAlchemy and Alembic Define models, query and change data with SQLAlchemy 2, and manage schema changes with Alembic migrations. 4 sections · 27 commands

Drupal Create, configure, update and debug Drupal 11 sites with Composer and Drush. 7 sections · 34 commands WordPress WP-CLI Install, configure, update and back up WordPress sites from the command line with WP-CLI 2. 7 sections · 48 commands

Node.js Everyday Node.js 24 and npm commands for running, testing and debugging projects. 4 sections · 27 commands

DuckDB Query CSV, Parquet and DataFrames with SQL from Python or the duckdb command line, without running a server. 3 sections · 23 commands Elasticsearch curl requests for indexes, documents, searches, bulk loads and cluster health. Security is on by default, so the examples authenticate. 4 sections · 26 commands MongoDB mongosh shell commands for documents, queries, aggregation, indexes, backups and administration. 6 sections · 48 commands MySQL mysql client, backup and maintenance commands for MySQL 8.4. 5 sections · 28 commands PostgreSQL psql, backup and maintenance commands for PostgreSQL 18. 5 sections · 30 commands Redis redis-cli and core commands for keys, data structures and server administration. 4 sections · 34 commands SQLite sqlite3 shell dot-commands, pragmas, import and export, and the SQL you use most. 6 sections · 37 commands

Ansible Run ad-hoc commands and playbooks, manage inventories, roles, collections and secrets with Ansible. 4 sections · 29 commands Apache Kafka Start a broker, manage topics, produce and consume messages, and inspect consumer groups. Run these from the Kafka install folder. 5 sections · 25 commands Argo CD Install Argo CD, define Applications declaratively, and manage sync, diffs, history and rollbacks with the argocd CLI. 4 sections · 25 commands AWS CLI Configure credentials and manage S3, EC2, Lambda, logs, containers and secrets with the AWS CLI v2. 5 sections · 32 commands Azure CLI Sign in and manage resource groups, VMs, web apps, storage, Kubernetes, registries and secrets with the az command. 5 sections · 34 commands Bash and Linux Everyday shell and Linux commands for files, searching text, permissions, processes and servers. 5 sections · 38 commands Claude API Call Claude from Python, TypeScript or curl: messages, streaming, thinking, tools, structured output, caching, batches and error handling. 6 sections · 32 commands Claude Code Run Claude Code in the terminal: starting sessions, slash commands, permissions, CLAUDE.md, hooks, MCP servers and headless use. 5 sections · 38 commands Composer Manage PHP dependencies, autoloading, scripts and project creation with Composer 2. 3 sections · 27 commands curl and jq Make HTTP requests with curl and slice JSON responses with jq, from the command line. 5 sections · 40 commands Docker Build, run and clean up containers and images, and manage multi-container apps with Docker Compose. 6 sections · 40 commands Docker Compose file compose.yaml snippets for services, ports, volumes, networks, environment, health checks, profiles and development workflows. 4 sections · 23 commands FFmpeg Convert, trim, resize, compress and inspect audio and video from the command line with ffmpeg and ffprobe. 4 sections · 31 commands Git Everyday Git commands for committing, branching, syncing and undoing mistakes. 6 sections · 45 commands GitHub Actions Workflow YAML snippets for triggers, jobs, caching, secrets, matrices, artifacts and deployment. 5 sections · 27 commands GitHub CLI Work with repositories, pull requests, issues, workflow runs and releases from your terminal with gh. 4 sections · 27 commands GitLab CI/CD .gitlab-ci.yml snippets for stages, jobs, rules, caching, artifacts, services, environments and reuse. 4 sections · 26 commands GNU Make Write Makefiles with targets, variables, pattern rules and phony targets, and the options for running make. 3 sections · 24 commands Google Cloud CLI (gcloud) Sign in and manage projects, Compute Engine, Cloud Run, storage, Kubernetes, logs and secrets with gcloud. 6 sections · 39 commands Helm Install, upgrade, inspect and roll back Kubernetes applications packaged as Helm charts. 4 sections · 24 commands HTTP Request methods, status codes, headers, caching, cookies and security headers, with curl commands to inspect them. 6 sections · 47 commands Jenkins Declarative Jenkinsfile syntax for stages, agents, credentials, parameters, parallel steps and notifications, plus running Jenkins. 4 sections · 23 commands Jupyter Run notebooks with JupyterLab, use IPython magics, register kernels, convert notebooks and run them from scripts. 4 sections · 23 commands kubectl Inspect, deploy, debug and scale workloads on a Kubernetes cluster. 6 sections · 41 commands Kubernetes manifests YAML for the Kubernetes resources you write most: Deployments, Services, Ingress, config, storage, probes, scaling and access control. 4 sections · 22 commands Linux networking Inspect interfaces, routes, ports and DNS, test connectivity, capture packets and manage firewalls with Linux networking tools. 5 sections · 36 commands Model Context Protocol (MCP) Build MCP servers in Python and TypeScript, test them with the Inspector, and connect them to Claude Code and Claude Desktop. 5 sections · 25 commands Nginx Control Nginx, test and reload configuration, and the config snippets for proxies, TLS, static sites and caching. 3 sections · 22 commands Ollama Run large language models locally: pull and run models, customize them with a Modelfile, call the REST API, and configure the server. 5 sections · 37 commands OpenSSL Generate keys and certificates, inspect and verify TLS certificates, convert formats, hash and encrypt with OpenSSL 3. 4 sections · 27 commands Prometheus and PromQL Query metrics with PromQL, and configure scraping, recording rules, alerts and the promtool checker. 4 sections · 28 commands SSH (OpenSSH) Connect to servers, manage keys, write ~/.ssh/config, forward ports, jump through bastion hosts and harden sshd. 5 sections · 33 commands systemd and journalctl Manage services, read logs, schedule timers and write unit files on Linux systems that use systemd. 4 sections · 35 commands Terraform Write, plan, apply and manage infrastructure as code with the Terraform CLI. 4 sections · 31 commands tmux Sessions, windows and panes in tmux, with the default Ctrl-b prefix, copy mode and configuration. 5 sections · 34 commands Vim Keystrokes for exiting, moving, editing, searching and working with files in Vim, including how to quit it. 9 sections · 78 commands