Bun is a

JavaScript JavaScript (), often abbreviated as JS, is a programming language and core technology of the World Wide Web, alongside HTML and CSS. Ninety-nine percent of websites use JavaScript on the client side for webpage behavior. Web browsers have ...

runtime,

package manager A package manager or package management system is a collection of software tools that automates the process of installing, upgrading, configuring, and removing computer programs for a computer in a consistent manner. A package manager deals wi ...

, test runner and bundler built from scratch using the Zig programming language. It was designed by Jarred Sumner as a drop-in replacement for Node.js. Bun uses

WebKit WebKit is a browser engine primarily used in Apple's Safari web browser, as well as all web browsers on iOS and iPadOS. WebKit is also used by the PlayStation consoles starting with the PS3, the Tizen mobile operating systems, the Amazon K ...

JavaScriptCore WebKit is a browser engine primarily used in Apple's Safari web browser, as well as all web browsers on iOS and iPadOS. WebKit is also used by the PlayStation consoles starting with the PS3, the Tizen mobile operating systems, the Amazon ...

as the

JavaScript engine The first engines for JavaScript were mere interpreters of the source code, but all relevant modern engines use just-in-time compilation for improved performance. JavaScript engines are typically developed by web browser vendors, and every maj ...

, unlike Node.js and Deno, which both use V8. It supports bundling, minifying, server-side rendering (

Svelte Svelte is a free and open-source component-based front-end software framework, and language created by Rich Harris and maintained by the Svelte core team members. Svelte is not a monolithic JavaScript library imported by applications: instead, ...

, Nuxt.js, Vite). Bundling refers to the process of combining multiple files and assets like

, CSS, and

HTML Hypertext Markup Language (HTML) is the standard markup language for documents designed to be displayed in a web browser. It defines the content and structure of web content. It is often assisted by technologies such as Cascading Style Sheets ( ...

into a single file, or a smaller number of files, to reduce the number of server requests and enhance performance. Minifying is a technique of compressing these files by removing unnecessary characters (like whitespace, comments, etc.) without affecting their functionality, further optimizing website loading times. Bun provides an API to decide whether to preserve some readability by e.g. keeping whitespace. The runtime supports

foreign function interface A foreign function interface (FFI) is a mechanism by which a program written in one programming language can call routines or make use of services written or compiled in another one. An FFI is often used in contexts where calls are made into a bin ...

(FFI),

SQLite3 SQLite ( "S-Q-L-ite", "sequel-ite") is a free and open-source relational database engine written in the C programming language. It is not a standalone app; rather, it is a library that software developers embed in their apps. As such, it ...

, TLS 1.3, and

DNS The Domain Name System (DNS) is a hierarchical and distributed name service that provides a naming system for computers, services, and other resources on the Internet or other Internet Protocol (IP) networks. It associates various informatio ...

resolution. It also comes bundled in with common tools like file editing,

HTTP HTTP (Hypertext Transfer Protocol) is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web, wher ...

servers,

Websocket WebSocket is a computer communications protocol, providing a full-duplex, simultaneous two-way communication channel over a single Transmission Control Protocol (TCP) connection. The WebSocket protocol was standardized by the Internet Engineering ...

, and hashing. The official Bun 1.0 was released on September 8, 2023. Since Bun 1.1 the runtime supports

Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

10 and later (along with

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

and

macOS macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...

). It also introduced a cross-platform Bun Shell for running some Bash commands without extra dependencies.

Funding

On August 24, 2022, Oven, the company behind Bun, announced it had raised $7 million in funding. The round was led by

Kleiner Perkins Kleiner Perkins, formerly Kleiner Perkins Caufield & Byers (KPCB), is an American venture capital firm which specializes in investing in incubation, early stage and growth companies. Since its founding in 1972, the firm has backed entrepreneur ...

, with participation from Guillermo Rauch,

Y Combinator Y Combinator, LLC (YC) is an American technology startup accelerator and venture capital firm launched in March 2005 which has been used to launch more than 5,000 companies. The accelerator program started in Boston and Mountain View, Californi ...

, and others.

References

External links

* 2022 software JavaScript software Software using the MIT license {{programming-software-stub