1. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M 第 十 六 届 D 2 前 坛 端 技 术 论 State of Deno 2022 Bartek Iwańczuk

2. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M What is Deno? What’s the state of Deno coming into 2022? Contents The Deno company 目录 Deno Deploy

3. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M What is Deno?

4. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M - Deno is a new command-line runtime for JavaScript and TypeScript - It aims to be fun and productive - A good scripting platform is too useful of a tool to accept the status quo

5. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M - First introduced on 13th May, 2018 in “10 Things I Regret About Node.js” talk - 1.0 was released on 13th May, 2020 - Currently at version 1.17

6. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Feature highlights - Deno is a single executable file - It will always be distributed this way - This single executable is all you need to run any Deno program - Work on Linux, Mac and Windows

7. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Feature highlights - TypeScript support out of the box - TypeScript compiler is part of the Deno binary, uses V8 snapshots to start up the compiler quickly for type checking - Transpilation, bundling and static analysis are done using SWC (Rust based JS/TS parser)

8. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Feature highlights - Secure execution by default - We want to enable people to run untrusted third part code > deno run https://deno.land/std/examples/welcome.ts Welcome to Deno 🦕 - To access disk, network or subprocesses the user must opt in with command line flags: —allow-read=/tmp —allow-net=google.com

9. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Feature highlights - Link to third party modules using URLs - Not dependent on a centralised server import { magenta } from “https://deno.land/std/fmt/colors.ts"; - The runtime fetches, caches and compile code transparently - Simple, browser compatible module system. No notion of node_modules or index.js (not really, more on that later)

10. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Feature highlights Deno uses Web Standard APIs wherever possible. If there’s an existing Web API that makes sense in the server environment Deno uses it, instead of inventing proprietary APIs. Deno uses Web Platform Tests to ensure compatibility. • • • • • • • • • • • • • • • • fetch Web Crypto Web Streams Web Workers Web Storage Web Sockets AbortController WebGPU Blob Location EventTarget TextEncoder TextDecoder onload, prompt(), confirm(), alert() many more...

11. Deno is listed on MDN’s compatibility tables D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M

12. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Feature highlights Deno includes whole JavaScript and TypeScript toolchain in a single executable. Everything you need to kickstart A project is already there. SUBCOMMANDS: bundle cache compile completions coverage doc eval fmt help info install lint lsp repl run test types upgrade Bundle module and dependencies into single file Cache the dependencies UNSTABLE: Compile the script into a self contained executable Generate shell completions Print coverage reports Show documentation for a module Eval script Format source files Prints this message or the help of the given subcommand(s) Show info about cache or info related to source file Install script as an executable UNSTABLE: Lint source files Start the language server Read Eval Print Loop Run a JavaScript or TypeScript program Run tests Print runtime TypeScript declarations Upgrade deno executable to given version

13. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Demo - - - - import { magenta } from "https://deno.land/std/fmt/colors.ts"; const url = Deno.args[0]; let res = await fetch(url); let server = res.headers.get("server")!; console.log("server:", magenta(server)); Get URL from the first command line argument Fetch URL Get “Server” header Print header to console (in magenta) $ deno run --allow-net curl.ts https://postman.com Server: nginx $ deno run --allow-net curl.ts https://www.cloudflare.com Server: cloudflare $ deno run --allow-net curl.ts https://github.com Server: GitHub.com

14. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Taking advantage of many technologies - - - - - - - V8 (Chrome’s JavaScript VM) Rust TypeScript (Microsoft) Tokio (async I/O framework for Rust) SWC (JS/TS parser) Rustls (TLS implementation) Hyper and Reqwest (HTTP server and client libraries) - - - - - - - wpgu (WebGPU backend) tungstenite (Websockets) trust-dns (Async DNS queries) rustyline (readline/REPL) notify (file system notifications) lspower (LSP framework for talking to IDEs) dprint (code formatter)

15. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M What’s state of Deno coming into 2022?

16. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M What’s state of Deno coming into 2022? - There’s one minor release and 2 to 4 patch releases every month (train model) - There were 17 minor versions and close to 100 patch versions released since May 2020 - We will continue to focus on web compatibility, better TypeScript support, and security - Standard library is seeing steady stream of updates and new APIs

17. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Increasing adoption Next generation data access API https://next.github.com/projects/flat-data

18. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Increasing adoption Next generation development platform from Slack https://api.slack.com/future

19. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Increasing adoption Jake Archibald

20. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M What’s state of Deno coming into 2022? - Deno is production ready, but there are many opinions that it can’t be used because it’s too different from Node.js ecosystem - In Autumn of 2021 we started a major effort of providing first-class Node.js compatibility (—compat mode) - Steady progress over the last two months, currently working on major modules like: http, https, tls, zlib - Aiming to achieve Node.js compatibility in Q2 of 2022 - Targeting wide frontend developers audience by providing compatibility with popular tools like Vite and Next.js

21. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Some existing Node.js tools already work in —compat mode

22. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M The Deno company

23. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M The Deno company - Deno remains free, MIT licensed - Commercial offering with Deno Deploy - 10 engineers and growing, including: - Ryan Dahl - Bert Belder - Ben Noordhuis - Kitson Kelly - Luca Caponato - David Sherret

24. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Deno Deploy

25. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Deno Deploy https://deno.com/deploy Deno Deploy is built using the same infrastructure as Deno CLI

26. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Deno Deploy https://deno.com/deploy - Playgrounds for quick and fun prototyping - Instant deployments across the world - Can be embedded in webpages or shared via a link

27. Contributing to Deno Contributions are welcome and much appreciated! - Deno has already over 600 contributors! - See https://deno.land/manual/contributing for the list of project you can contribute to. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M

28. D2 前 端 技 术 论 坛 D 2 F R O N T E N D T E C H N O LO G Y F O R U M Thank you! Time for questions! E-mail: bartek@deno.com https://deno.land https://deno.com