12 Must‑Have Open‑Source Tools Every Developer Should Use

Developers, it’s time for open‑source tools! Below are twelve carefully selected open‑source utilities that can become indispensable in your toolkit.

1. Theia

When looking for a truly open‑source alternative to VS Code, consider Theia. It is a flexible IDE that runs in the cloud and on the desktop, built with TypeScript and offering a rich plugin ecosystem.

Cloud and desktop IDE capabilities

Extensible plugin system supporting VS Code extensions

Multi‑language support

Website: https://theia-ide.org/

GitHub: https://github.com/eclipse-theia/theia

2. Postman

Postman lets you chain requests, automate tasks, and collaborate, making API usage easier. If you don’t like cURL, Postman is a solid alternative.

API testing and automation

Request chaining for complex workflows

Team collaboration tools

Website: https://www.postman.com/

GitHub: https://github.com/postmanlabs/postman-app-support

3. Hoppscotch

Hoppscotch is a free, lightweight, fast, and beautiful API request builder that lets you quickly create and test APIs.

HTTP methods (GET, POST, PUT, DELETE, PATCH, etc.)

Built‑in GraphQL support

Collection management and environment variables

Website: https://hoppscotch.io/

GitHub: https://github.com/hoppscotch/hoppscotch

4. Pocketbase

Pocketbase is an open‑source real‑time backend in a single file, usable with Flutter, Vue, React, and Angular. It is written in Go and provides a simple, reliable SQLite‑based database.

Embedded real‑time subscription database (SQLite)

Built‑in file and user management

Simple REST‑ish API

Website: https://pocketbase.io/

GitHub: https://github.com/pocketbase/pocketbase

5. cURL

cURL is a simple command‑line tool for calling APIs, bundled with most Linux and macOS distributions.

Supports multiple protocols (HTTP, FTP, etc.)

Scriptable command‑line interface

Website: https://curl.se/

GitHub: https://github.com/curl/curl

6. Waveterm

Waveterm is an open‑source AI‑native terminal that combines the command line with networked services to boost developer efficiency.

Session persistence across network disconnects and restarts

Searchable contextual command history

CodeEdit: VS Code‑like inline editor for local and remote files

AI integration with ChatGPT‑compatible APIs for command generation and answers

Website: https://www.waveterm.dev/

GitHub: https://github.com/wavetermdev/waveterm

7. Ollama

Ollama focuses on running large language models locally, essentially providing a Docker‑Desktop‑like experience for LLMs.

Local LLM testing

Development environment for large language models

OpenAI‑compatible API

Website: https://ollama.com/

GitHub: https://github.com/ollama/ollama

8. LM Studio

LM‑Studio is a competitor to Ollama, offering local LLM testing with an OpenAI‑compatible API and Windows support.

Local LLM testing

OpenAI‑compatible API

Supports Windows PCs

Website: https://lmstudio.ai/

GitHub: https://github.com/lmstudio-ai

9. VS Code

VS Code is an open‑source code editor that many developers start with; its extension ecosystem is massive.

Extensible code editor

Debugging support

Rich extension ecosystem

Website: https://code.visualstudio.com/

GitHub: https://github.com/microsoft/vscode

10. Docker Compose

Docker Compose simplifies defining and running multi‑container Docker applications using a simple compose.yaml file.

Container orchestration

Service definition with YAML

Multi‑container application management

Website: https://docs.docker.com/compose/

GitHub: https://github.com/docker/compose

11. ESLint

ESLint is a powerful tool for JavaScript and TypeScript that enforces coding standards via configurable linting rules and plugins.

Code quality analysis

Configurable linting rules

Support for JavaScript and TypeScript

Website: https://eslint.org/

GitHub: https://github.com/eslint/eslint

12. Oh My Zsh

Oh My Zsh enhances your Zsh shell with cool themes and plugins, improving the terminal experience.

Zsh configuration management

Customizable themes and plugins

Community‑driven development

Website: https://ohmyz.sh/

GitHub: https://github.com/ohmyzsh/ohmyzsh

These twelve open‑source tools can significantly boost your development workflow—are you willing to give up a slice of pizza for them?