Wisp: A Fast, Fun Web Framework for Rust

$ cargo install --git https://wisp.ar0.eu/ --tag v1.0.0-pre.3 wisp-web

src/routes/+page.wisp

---
#[model]
struct Todo {
    #[validate(len = 1..=100)]
    text: String,
}

static TODOS: Table<Todo> = Table::saved();

#[action]
fn add(todo: Todo) {
    TODOS.add(todo)?;
}

#[action]
fn remove(id: u64) {
    TODOS.remove(id)?;
}
---

<title>Todos (${TODOS.len()})</title>
<meta name="description" content="A todo list that saves its rows and checks what you add.">
<h1>Todos</h1>

<form action="?/add" fields />

{#each TODOS.all() as todo}
  <p> ${todo.text}
    <button action="?/remove&id=${todo.id}">
      Remove
    </button>
  </p>
{/each}

localhost:3000

Todos (3)

Buy milk
Write the docs
Learn to code

A Page Is One File

Put the model, the form actions and the markup of a page in one file. Wisp compiles the file to Rust, so the compiler checks your template as it checks the rest of your code.

See Wisp Run

Watch the Wisp 1.0 showcase. The video loads from YouTube only after you press play.

Wisp 1.0 Showcase Watch on YouTube

Benchmarks

Each framework runs on the same machine with a release build. The charts show every contender, also the tests where Wisp loses.

TechEmpower plaintext and JSON tests. Not an official TechEmpower result.

Plaintext, pipelinedreq/s, 16 requests per write, best of 256 to 16,384 connections
Wisp		8,140,071
Actix Web		3,584,014
Axum		2,390,269
Hono (Bun)		603,962
Fastify		414,802
Express		278,367
Hono (Node.js)		217,621
Nuxt		165,092
SvelteKit		104,899
Next.js		15,129

JSONreq/s, one request per write, best of 16 to 512 connections
Wisp		1,160,729
Actix Web		878,655
Axum		749,723
Hono (Bun)		526,427
Fastify		323,353
Express		241,238
Hono (Node.js)		190,174
Nuxt		187,113
SvelteKit		96,149
Next.js		8,639

Text Reply, GET /req/s
Wisp		282,805
Fastify		138,978
Hono		134,428
Express		90,808

HTML Page of 1,000 Rowsreq/s
Wisp		15,217
Fastify		4,312
SvelteKit		2,252

JSON of 200 Objectsreq/s
Wisp		43,720
Fastify		27,286
Hono		27,096
Express		21,272
Next.js		5,060

Path, Query and Cookie Parsingreq/s
Wisp		261,630
Fastify		127,917
Hono		107,559
Express		83,322
Next.js		4,528

Cold Startms
Wisp		26
SvelteKit		42
Fastify		62
Next.js		155

Memory Under Load (RSS)MB
Wisp		80
Fastify		234
Express		241
Hono		248
Next.js		517
SvelteKit		614

Text Reply, GET /req/s
Wisp		407,546
Elysia		392,406
Hono		370,767

JSON of 200 Objectsreq/s
Wisp		53,412
Hono		39,021
Elysia		38,826

Path, Query and Cookie Parsingreq/s
Wisp		365,756
Hono		280,910
Elysia		245,795

Cold Startms
Hono		7
Wisp		11
Elysia		20

Memory Under Load (RSS)MB
Wisp		48
Hono		70
Elysia		83

Text Reply, GET /req/s
Hono		355,860
Wisp		298,471
Fresh		205,214

HTML Page of 1,000 Rowsreq/s
Wisp		13,176
Hono		4,841

JSON of 200 Objectsreq/s
Hono		40,377
Wisp		37,506
Fresh		36,492
Oak		35,709

Path, Query and Cookie Parsingreq/s
Hono		251,174
Wisp		223,894
Oak		133,827
Fresh		80,792

Cold Startms
Wisp		18
Fresh		24
Oak		38

Memory Under Load (RSS)MB
Wisp		60
Hono		113
Oak		154
Fresh		175

Text Reply, GET /req/s
Wisp		42,503
Hono		41,176
itty-router		38,123
Astro		23,753
SvelteKit		19,931
React Router		18,999
Next.js		2,608

HTML Page of 1,000 Rowsreq/s
Wisp		10,916
Astro		4,083
SvelteKit		2,338
Next.js		195

JSON of 200 Objectsreq/s
Wisp		20,548
Hono		19,102
itty-router		18,210
React Router		11,936
Next.js		2,039

Path, Query and Cookie Parsingreq/s
Wisp		39,731
Hono		37,523
Astro		21,396
React Router		16,535
Next.js		2,163

Cold Startms
itty-router		12
Hono		13
Wisp		19
SvelteKit		20
React Router		23
Astro		30
Next.js		92

Memory Under Load (RSS)MB
Hono		335
Wisp		369
React Router		440
itty-router		479
Astro		553
Next.js		923
SvelteKit		1,491

HTML Page of 1,000 Rowsreq/s
Axum		57,053
Actix Web		55,863
Wisp		54,292
ASP.NET Core		25,466
Spring Boot		25,449
Fastify		8,527
Express		8,438
FastAPI		5,039
SvelteKit		3,675
Go Gin		3,099
Next.js		257

JSON of 200 Objectsreq/s
Hono (Bun)		74,533
Wisp		69,166
Fastify		60,713
Actix Web		58,507
Express		54,097
ASP.NET Core		53,121
Go Gin		44,635
SvelteKit		35,856
Next.js		6,958
FastAPI		1,955

Memory Under Load (PSS)MB
Actix Web		3
Axum		4
Wisp		5
Go Gin		21
Hono (Bun)		45
ASP.NET Core		86
FastAPI		103
Fastify		186
Express		398
Spring Boot		778
Next.js		961
SvelteKit		3,429

How we measured, and the full tables

Forms Without JavaScript

Rules on the model check each value on the server. A bad value comes back with its error next to the input, and the form works without JavaScript.

src/db.rs +page.wisp

#[model]
struct User {
    #[unique]
    email: Email,
    password: Password,
}
pub static USERS: Table<User> = Table::saved();

---
#[action]
fn signup(email: Email, password: Password) {
    cx.signup(User { email, password }).await?;
    redirect("/me")
}
---

<form action="?/signup" fields>
  <button>Sign up</button>
</form>

Reactivity in the Same File

Server values render in Rust when the page loads. Browser state lives in the same file and updates the page when it changes.

---
let name = cx.query_or("name", "world".to_string());
---

<h1>Hello, ${name}!</h1>

<button on:click="count++">Clicked {:count} times</button>

NPM Packages in the Browser

Add a package with wisp npm add, then import it in a page script. The build keeps a copy of the package, so you do not need Node.

wisp npm add canvas-confetti

+page.wisp

<button on:click="party()">Ship it</button>

<script lang="ts">
  import confetti from 'canvas-confetti'

  function party() {
    confetti({ particleCount: 120, spread: 70 })
  }
</script>

NPM in browser code · React, Vue and Svelte islands

Fewer Tokens

Less code for you to write, and fewer tokens when an AI writes it. We wrote one small app in each stack and counted its tokens.

Stack	Tokens	Files
Wisp	477	7
Nuxt	1,043	8
SvelteKit	1,134	9
Next.js	1,146	8
Express	1,297	8
React	1,599	9
Axum	1,803	7
Actix Web	1,878	7

claude mcp add wisp -- wisp mcp

How Tokens Are Counted

Editors

wisp lsp gives highlighting, completion, hover docs and diagnostics. The hover docs come from the Wisp source: its doc comments and its hover tables.

wisp lsp

Install for VS Code Other Editors

One Binary

wisp build makes one binary that serves the whole app. You can also ship a container, static HTML, or an edge build.

wisp build
wisp build --static
wisp deploy init docker
wisp build --target cloudflare
wisp deploy init cloudflare

Install Wisp