diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index c654e23302..d3ca3eeea7 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -47,7 +47,7 @@ jobs:
           rustup component add clippy
           rustup target add wasm32-unknown-unknown
       - uses: Swatinem/rust-cache@v1
-      - run: cargo clippy -p ruff --target wasm32-unknown-unknown --all-features -- -D warnings
+      - run: cargo clippy -p ruff_wasm --target wasm32-unknown-unknown --all-features -- -D warnings
 
   cargo-test:
     strategy:
@@ -80,6 +80,26 @@ jobs:
           # Setting RUSTDOCFLAGS because `cargo doc --check` isn't yet implemented (https://github.com/rust-lang/cargo/issues/10025).
           RUSTDOCFLAGS: "-D warnings"
 
+
+  cargo-test-wasm:
+    runs-on: ubuntu-latest
+    name: "cargo test (wasm)"
+    steps:
+      - uses: actions/checkout@v3
+      - name: "Install Rust toolchain"
+        run: rustup target add wasm32-unknown-unknown
+      - uses: actions/setup-node@v3
+        with:
+          node-version: 18
+          cache: "npm"
+          cache-dependency-path: playground/package-lock.json
+      - uses: jetli/wasm-pack-action@v0.4.0
+      - uses: Swatinem/rust-cache@v1
+      - name: "Run wasm-pack"
+        run: |
+          cd crates/ruff_wasm
+          wasm-pack test --node
+
   scripts:
     name: "test scripts"
     runs-on: ubuntu-latest
diff --git a/.github/workflows/playground.yaml b/.github/workflows/playground.yaml
index a5c58fe03c..40060bcbb7 100644
--- a/.github/workflows/playground.yaml
+++ b/.github/workflows/playground.yaml
@@ -28,7 +28,7 @@ jobs:
       - uses: jetli/wasm-pack-action@v0.4.0
       - uses: jetli/wasm-bindgen-action@v0.2.0
       - name: "Run wasm-pack"
-        run: wasm-pack build --target web --out-dir ../../playground/src/pkg crates/ruff
+        run: wasm-pack build --target web --out-dir ../../playground/src/pkg crates/ruff_wasm
       - name: "Install Node dependencies"
         run: npm ci
         working-directory: playground
diff --git a/Cargo.lock b/Cargo.lock
index e11a2d247f..7a08d9e3a1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -608,17 +608,6 @@ dependencies = [
  "syn",
 ]
 
-[[package]]
-name = "derivative"
-version = "2.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fcc3dd5e9e9c0b295d6e1e4d811fb6f157d5ffd784b8d202fc62eac8035a770b"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]
-
 [[package]]
 name = "diff"
 version = "0.1.13"
@@ -1969,17 +1958,12 @@ dependencies = [
  "anyhow",
  "bisection",
  "bitflags",
- "cfg-if",
  "chrono",
  "clap 4.1.8",
  "colored",
- "console_error_panic_hook",
- "console_log",
  "criterion",
- "derivative",
  "dirs",
  "fern",
- "getrandom",
  "glob",
  "globset",
  "ignore",
@@ -1987,7 +1971,6 @@ dependencies = [
  "insta",
  "is-macro",
  "itertools",
- "js-sys",
  "libcst",
  "log",
  "natord",
@@ -2009,7 +1992,6 @@ dependencies = [
  "schemars",
  "semver",
  "serde",
- "serde-wasm-bindgen",
  "shellexpand",
  "smallvec",
  "strum",
@@ -2018,8 +2000,6 @@ dependencies = [
  "textwrap",
  "thiserror",
  "toml",
- "wasm-bindgen",
- "wasm-bindgen-test",
 ]
 
 [[package]]
@@ -2190,7 +2170,6 @@ name = "ruff_testing_macros"
 version = "0.0.0"
 dependencies = [
  "glob",
- "proc-macro-error",
  "proc-macro2",
  "quote",
  "syn",
@@ -2206,6 +2185,25 @@ dependencies = [
  "static_assertions",
 ]
 
+[[package]]
+name = "ruff_wasm"
+version = "0.0.0"
+dependencies = [
+ "console_error_panic_hook",
+ "console_log",
+ "getrandom",
+ "js-sys",
+ "log",
+ "ruff",
+ "ruff_python_ast",
+ "ruff_rustpython",
+ "rustpython-parser",
+ "serde",
+ "serde-wasm-bindgen",
+ "wasm-bindgen",
+ "wasm-bindgen-test",
+]
+
 [[package]]
 name = "rust-stemmers"
 version = "1.2.0"
@@ -2411,9 +2409,9 @@ dependencies = [
 
 [[package]]
 name = "serde-wasm-bindgen"
-version = "0.4.5"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e3b4c031cd0d9014307d82b8abf653c0290fbdaeb4c02d00c63cf52f728628bf"
+checksum = "f3b143e2833c57ab9ad3ea280d21fd34e285a42837aeb0ee301f4f41890fa00e"
 dependencies = [
  "js-sys",
  "serde",
diff --git a/crates/ruff/Cargo.toml b/crates/ruff/Cargo.toml
index 8d8f1f3f13..2b570b9825 100644
--- a/crates/ruff/Cargo.toml
+++ b/crates/ruff/Cargo.toml
@@ -25,11 +25,9 @@ ruff_rustpython = { path = "../ruff_rustpython" }
 anyhow = { workspace = true }
 bisection = { version = "0.1.0" }
 bitflags = { workspace = true }
-cfg-if = { version = "1.0.0" }
 chrono = { workspace = true }
 clap = { workspace = true, features = ["derive", "env", "string"] }
 colored = { workspace = true }
-derivative = { version = "2.2.0" }
 dirs = { version = "4.0.0" }
 fern = { version = "0.6.1" }
 glob = { workspace = true }
@@ -65,23 +63,12 @@ textwrap = { workspace = true }
 thiserror = { version = "1.0.38" }
 toml = { workspace = true }
 
-# https://docs.rs/getrandom/0.2.7/getrandom/#webassembly-support
-[target.'cfg(all(target_family = "wasm", target_os = "unknown"))'.dependencies]
-getrandom = { version = "0.2.8", features = ["js"] }
-console_error_panic_hook = { version = "0.1.7" }
-console_log = { version = "0.2.1" }
-serde-wasm-bindgen = { version = "0.4.5" }
-js-sys = { version = "0.3.61" }
-wasm-bindgen = { version = "0.2.84" }
-
 [dev-dependencies]
 insta = { workspace = true, features = ["yaml", "redactions"] }
 test-case = { workspace = true }
-wasm-bindgen-test = { version = "0.3.34" }
-
-[target.'cfg(not(target_family = "wasm"))'.dev-dependencies]
 criterion = { version = "0.4.0" }
 
+
 [features]
 default = []
 logical_lines = []
diff --git a/crates/ruff/src/codes.rs b/crates/ruff/src/codes.rs
index b8a819cc25..454372db3e 100644
--- a/crates/ruff/src/codes.rs
+++ b/crates/ruff/src/codes.rs
@@ -1,5 +1,23 @@
 use crate::registry::{Linter, Rule};
 
+#[derive(PartialEq, Eq, PartialOrd, Ord)]
+pub struct NoqaCode(&'static str, &'static str);
+
+impl std::fmt::Display for NoqaCode {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
+        write!(f, "{}{}", self.0, self.1)
+    }
+}
+
+impl PartialEq<&str> for NoqaCode {
+    fn eq(&self, other: &&str) -> bool {
+        match other.strip_prefix(self.0) {
+            Some(suffix) => suffix == self.1,
+            None => false,
+        }
+    }
+}
+
 #[ruff_macros::map_codes]
 pub fn code_to_rule(linter: Linter, code: &str) -> Option<Rule> {
     #[allow(clippy::enum_glob_use)]
diff --git a/crates/ruff/src/lib.rs b/crates/ruff/src/lib.rs
index 9b0b529a3e..c792e2f3f6 100644
--- a/crates/ruff/src/lib.rs
+++ b/crates/ruff/src/lib.rs
@@ -5,7 +5,6 @@
 //!
 //! [Ruff]: https://github.com/charliermarsh/ruff
 
-use cfg_if::cfg_if;
 pub use ruff_python_ast::source_code::round_trip;
 pub use ruff_python_ast::types::Range;
 pub use rule_selector::RuleSelector;
@@ -16,7 +15,7 @@ mod autofix;
 mod checkers;
 mod codes;
 mod cst;
-mod directives;
+pub mod directives;
 mod doc_lines;
 mod docstrings;
 pub mod fix;
@@ -27,22 +26,14 @@ pub mod linter;
 pub mod logging;
 pub mod message;
 mod noqa;
+pub mod packaging;
 pub mod registry;
 pub mod resolver;
 mod rule_redirects;
 mod rule_selector;
-mod rules;
+pub mod rules;
 pub mod settings;
 mod violation;
 
-cfg_if! {
-    if #[cfg(target_family = "wasm")] {
-        mod lib_wasm;
-        pub use lib_wasm::check;
-    } else {
-        pub mod packaging;
-    }
-}
-
 #[cfg(test)]
 mod test;
diff --git a/crates/ruff/src/registry.rs b/crates/ruff/src/registry.rs
index 69d59f599b..e99b6e62c0 100644
--- a/crates/ruff/src/registry.rs
+++ b/crates/ruff/src/registry.rs
@@ -611,6 +611,20 @@ ruff_macros::register_rules!(
     rules::flake8_django::rules::NonLeadingReceiverDecorator,
 );
 
+impl Rule {
+    pub fn from_code(code: &str) -> Result<Self, FromCodeError> {
+        let (linter, code) = Linter::parse_code(code).ok_or(FromCodeError::Unknown)?;
+        let prefix: RuleCodePrefix = RuleCodePrefix::parse(&linter, code)?;
+        Ok(prefix.into_iter().next().unwrap())
+    }
+}
+
+#[derive(thiserror::Error, Debug)]
+pub enum FromCodeError {
+    #[error("unknown rule code")]
+    Unknown,
+}
+
 #[derive(EnumIter, Debug, PartialEq, Eq, Clone, Hash, RuleNamespace)]
 pub enum Linter {
     /// [Pyflakes](https://pypi.org/project/pyflakes/)
diff --git a/crates/ruff_macros/src/map_codes.rs b/crates/ruff_macros/src/map_codes.rs
index bae55028fb..32036ac1f4 100644
--- a/crates/ruff_macros/src/map_codes.rs
+++ b/crates/ruff_macros/src/map_codes.rs
@@ -156,27 +156,16 @@ pub fn map_codes(func: &ItemFn) -> syn::Result<TokenStream> {
 
     out.extend(quote! {
         impl RuleCodePrefix {
-            pub fn parse(linter: &Linter, code: &str) -> Result<Self, FromCodeError> {
+            pub fn parse(linter: &Linter, code: &str) -> Result<Self, crate::registry::FromCodeError> {
                 use std::str::FromStr;
 
                 Ok(match linter {
-                    #(Linter::#linter_idents => RuleCodePrefix::#linter_idents(#linter_idents::from_str(code).map_err(|_| FromCodeError::Unknown)?),)*
+                    #(Linter::#linter_idents => RuleCodePrefix::#linter_idents(#linter_idents::from_str(code).map_err(|_| crate::registry::FromCodeError::Unknown)?),)*
                 })
             }
         }
     });
 
-    out.extend(quote! {
-        impl crate::registry::Rule {
-            pub fn from_code(code: &str) -> Result<Self, FromCodeError> {
-                use crate::registry::RuleNamespace;
-                let (linter, code) = Linter::parse_code(code).ok_or(FromCodeError::Unknown)?;
-                let prefix: RuleCodePrefix = RuleCodePrefix::parse(&linter, code)?;
-                Ok(prefix.into_iter().next().unwrap())
-            }
-        }
-    });
-
     #[allow(clippy::type_complexity)]
     let mut rule_to_codes: HashMap<&Path, Vec<(&Ident, &String, &Vec<Attribute>)>> = HashMap::new();
     let mut linter_code_for_rule_match_arms = quote!();
@@ -245,25 +234,6 @@ pub fn map_codes(func: &ItemFn) -> syn::Result<TokenStream> {
                 }
             }
         }
-
-        #[derive(PartialEq, Eq, PartialOrd, Ord)]
-        pub struct NoqaCode(&'static str, &'static str);
-
-        impl std::fmt::Display for NoqaCode {
-            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
-                use std::fmt::Write;
-                write!(f, "{}{}", self.0, self.1)
-            }
-        }
-
-        impl PartialEq<&str> for NoqaCode {
-            fn eq(&self, other: &&str) -> bool {
-                match other.strip_prefix(self.0) {
-                    Some(suffix) => suffix == self.1,
-                    None => false
-                }
-            }
-        }
     });
 
     let mut linter_into_iter_match_arms = quote!();
@@ -295,12 +265,6 @@ pub fn map_codes(func: &ItemFn) -> syn::Result<TokenStream> {
                 vec![ #(#all_codes,)* ].into_iter()
             }
         }
-
-        #[derive(thiserror::Error, Debug)]
-        pub enum FromCodeError {
-            #[error("unknown rule code")]
-            Unknown,
-        }
     });
 
     Ok(out)
diff --git a/crates/ruff_macros/src/rule_code_prefix.rs b/crates/ruff_macros/src/rule_code_prefix.rs
index 8171bf9430..3485cd9734 100644
--- a/crates/ruff_macros/src/rule_code_prefix.rs
+++ b/crates/ruff_macros/src/rule_code_prefix.rs
@@ -66,12 +66,12 @@ pub fn expand<'a>(
         }
 
         impl std::str::FromStr for #prefix_ident {
-            type Err = FromCodeError;
+            type Err = crate::registry::FromCodeError;
 
             fn from_str(code: &str) -> Result<Self, Self::Err> {
                 match code {
                     #(#attributes #variant_strs => Ok(Self::#variant_idents),)*
-                    _ => Err(FromCodeError::Unknown)
+                    _ => Err(crate::registry::FromCodeError::Unknown)
                 }
             }
         }
diff --git a/crates/ruff_testing_macros/Cargo.toml b/crates/ruff_testing_macros/Cargo.toml
index 88e0f6ae72..aeffa59469 100644
--- a/crates/ruff_testing_macros/Cargo.toml
+++ b/crates/ruff_testing_macros/Cargo.toml
@@ -11,7 +11,6 @@ proc-macro = true
 
 [dependencies]
 glob = { workspace = true }
-proc-macro-error = { version = "1.0.4", default-features = false }
 proc-macro2 = { workspace = true }
 quote = { workspace = true }
 syn = { workspace = true }
diff --git a/crates/ruff_wasm/Cargo.toml b/crates/ruff_wasm/Cargo.toml
new file mode 100644
index 0000000000..a6fcd0b916
--- /dev/null
+++ b/crates/ruff_wasm/Cargo.toml
@@ -0,0 +1,30 @@
+[package]
+name = "ruff_wasm"
+version = "0.0.0"
+publish = false
+edition = { workspace = true }
+rust-version = { workspace = true }
+description = "WebAssembly bindings for Ruff"
+
+[lib]
+crate-type = ["cdylib", "rlib"]
+
+[features]
+default = ["console_error_panic_hook"]
+
+[dependencies]
+console_log = { version = "0.2.1" }
+getrandom = { version = "0.2.8", features = ["js"] }
+log = { workspace = true }
+ruff = { path = "../ruff" }
+ruff_python_ast = { path = "../ruff_python_ast" }
+ruff_rustpython = { path = "../ruff_rustpython" }
+rustpython-parser = { workspace = true }
+serde = { workspace = true }
+serde-wasm-bindgen = { version = "0.5.0" }
+wasm-bindgen = { version = "0.2.84" }
+console_error_panic_hook = { version = "0.1.7", optional = true }
+
+[dev-dependencies]
+js-sys = { version = "0.3.61" }
+wasm-bindgen-test = { version = "0.3.34" }
diff --git a/crates/ruff/src/lib_wasm.rs b/crates/ruff_wasm/src/lib.rs
similarity index 73%
rename from crates/ruff/src/lib_wasm.rs
rename to crates/ruff_wasm/src/lib.rs
index ae37654563..4d36aa978d 100644
--- a/crates/ruff/src/lib_wasm.rs
+++ b/crates/ruff_wasm/src/lib.rs
@@ -2,21 +2,20 @@ use std::path::Path;
 
 use rustpython_parser::ast::Location;
 use rustpython_parser::lexer::LexResult;
-use serde::Serialize;
+use serde::{Deserialize, Serialize};
 use wasm_bindgen::prelude::*;
 
-use crate::directives;
-use crate::linter::{check_path, LinterResult};
-use crate::registry::{AsRule, Rule};
-use crate::rules::{
+use ruff::directives;
+use ruff::linter::{check_path, LinterResult};
+use ruff::rules::{
     flake8_annotations, flake8_bandit, flake8_bugbear, flake8_builtins, flake8_comprehensions,
     flake8_errmsg, flake8_implicit_str_concat, flake8_import_conventions, flake8_pytest_style,
     flake8_quotes, flake8_self, flake8_tidy_imports, flake8_type_checking, flake8_unused_arguments,
     isort, mccabe, pep8_naming, pycodestyle, pydocstyle, pylint, pyupgrade,
 };
-use crate::settings::configuration::Configuration;
-use crate::settings::options::Options;
-use crate::settings::{defaults, flags, Settings};
+use ruff::settings::configuration::Configuration;
+use ruff::settings::options::Options;
+use ruff::settings::{defaults, flags, Settings};
 use ruff_python_ast::source_code::{Indexer, Locator, Stylist};
 
 const VERSION: &str = env!("CARGO_PKG_VERSION");
@@ -49,34 +48,17 @@ export interface Diagnostic {
 };
 "#;
 
-#[derive(Serialize)]
-struct ExpandedMessage<'a> {
-    code: SerializeRuleAsCode<'a>,
-    message: String,
-    location: Location,
-    end_location: Location,
-    fix: Option<ExpandedFix>,
+#[derive(Serialize, Deserialize, Eq, PartialEq, Debug)]
+pub struct ExpandedMessage {
+    pub code: String,
+    pub message: String,
+    pub location: Location,
+    pub end_location: Location,
+    pub fix: Option<ExpandedFix>,
 }
 
-struct SerializeRuleAsCode<'a>(&'a Rule);
-
-impl Serialize for SerializeRuleAsCode<'_> {
-    fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
-    where
-        S: serde::Serializer,
-    {
-        serializer.serialize_str(&self.0.noqa_code().to_string())
-    }
-}
-
-impl<'a> From<&'a Rule> for SerializeRuleAsCode<'a> {
-    fn from(rule: &'a Rule) -> Self {
-        Self(rule)
-    }
-}
-
-#[derive(Serialize)]
-struct ExpandedFix {
+#[derive(Serialize, Deserialize, Eq, PartialEq, Debug)]
+pub struct ExpandedFix {
     content: String,
     message: Option<String>,
     location: Location,
@@ -86,7 +68,16 @@ struct ExpandedFix {
 #[wasm_bindgen(start)]
 pub fn run() {
     use log::Level;
+
+    // When the `console_error_panic_hook` feature is enabled, we can call the
+    // `set_panic_hook` function at least once during initialization, and then
+    // we will get better error messages if our code ever panics.
+    //
+    // For more details see
+    // https://github.com/rustwasm/console_error_panic_hook#readme
+    #[cfg(feature = "console_error_panic_hook")]
     console_error_panic_hook::set_once();
+
     console_log::init_with_level(Level::Debug).expect("Initializing logger went wrong.");
 }
 
@@ -208,8 +199,8 @@ pub fn check(contents: &str, options: JsValue) -> Result<JsValue, JsValue> {
     let messages: Vec<ExpandedMessage> = diagnostics
         .into_iter()
         .map(|message| ExpandedMessage {
-            code: message.kind.rule().into(),
-            message: message.kind.body.clone(),
+            code: message.kind.name,
+            message: message.kind.body,
             location: message.location,
             end_location: message.end_location,
             fix: message.fix.map(|fix| ExpandedFix {
@@ -223,55 +214,3 @@ pub fn check(contents: &str, options: JsValue) -> Result<JsValue, JsValue> {
 
     Ok(serde_wasm_bindgen::to_value(&messages)?)
 }
-
-#[cfg(test)]
-mod test {
-    use js_sys;
-    use wasm_bindgen_test::*;
-
-    use super::*;
-
-    macro_rules! check {
-        ($source:expr, $config:expr, $expected:expr) => {{
-            let foo = js_sys::JSON::parse($config).unwrap();
-            match check($source, foo) {
-                Ok(output) => {
-                    let result: Vec<Message> = serde_wasm_bindgen::from_value(output).unwrap();
-                    assert_eq!(result, $expected);
-                }
-                Err(e) => assert!(false, "{:#?}", e),
-            }
-        }};
-    }
-
-    #[wasm_bindgen_test]
-    fn empty_config() {
-        check!(
-            "if (1, 2): pass",
-            r#"{}"#,
-            [ExpandedMessage {
-                code: Rule::IfTuple.into(),
-                message: "If test is a tuple, which is always `True`".to_string(),
-                location: Location::new(1, 0),
-                end_location: Location::new(1, 15),
-                fix: None,
-            }]
-        );
-    }
-
-    #[wasm_bindgen_test]
-    fn partial_config() {
-        check!("if (1, 2): pass", r#"{"ignore": ["F"]}"#, []);
-    }
-
-    #[wasm_bindgen_test]
-    fn partial_nested_config() {
-        let config = r#"{
-          "select": ["Q"],
-          "flake8-quotes": {
-            "inline-quotes": "single"
-          }
-        }"#;
-        check!(r#"print('hello world')"#, config, []);
-    }
-}
diff --git a/crates/ruff_wasm/tests/api.rs b/crates/ruff_wasm/tests/api.rs
new file mode 100644
index 0000000000..3c9c4ea55b
--- /dev/null
+++ b/crates/ruff_wasm/tests/api.rs
@@ -0,0 +1,52 @@
+#![cfg(target_arch = "wasm32")]
+
+use js_sys;
+use rustpython_parser::ast::Location;
+use wasm_bindgen_test::*;
+
+use ruff::registry::Rule;
+use ruff_wasm::*;
+
+macro_rules! check {
+    ($source:expr, $config:expr, $expected:expr) => {{
+        let foo = js_sys::JSON::parse($config).unwrap();
+        match check($source, foo) {
+            Ok(output) => {
+                let result: Vec<ExpandedMessage> = serde_wasm_bindgen::from_value(output).unwrap();
+                assert_eq!(result, $expected);
+            }
+            Err(e) => assert!(false, "{:#?}", e),
+        }
+    }};
+}
+
+#[wasm_bindgen_test]
+fn empty_config() {
+    check!(
+        "if (1, 2):\n pass",
+        r#"{}"#,
+        [ExpandedMessage {
+            code: Rule::IfTuple.noqa_code().to_string(),
+            message: "If test is a tuple, which is always `True`".to_string(),
+            location: Location::new(1, 0),
+            end_location: Location::new(2, 5),
+            fix: None,
+        }]
+    );
+}
+
+#[wasm_bindgen_test]
+fn partial_config() {
+    check!("if (1, 2):\n pass", r#"{"ignore": ["F"]}"#, []);
+}
+
+#[wasm_bindgen_test]
+fn partial_nested_config() {
+    let config = r#"{
+          "select": ["Q"],
+          "flake8-quotes": {
+            "inline-quotes": "single"
+          }
+        }"#;
+    check!(r#"print('hello world')"#, config, []);
+}
diff --git a/playground/README.md b/playground/README.md
index f5bf4e9e0c..befd81a0af 100644
--- a/playground/README.md
+++ b/playground/README.md
@@ -4,7 +4,7 @@ In-browser playground for Ruff. Available [https://play.ruff.rs/](https://play.r
 
 ## Getting started
 
-- To build the WASM module, run `wasm-pack build ../crates/ruff --target web --out-dir ../../playground/src/pkg`
+- To build the WASM module, run `wasm-pack build ../crates/ruff_wasm --target web --out-dir ../../playground/src/pkg`
   from the `./playground` directory.
 - Install TypeScript dependencies with: `npm install`.
 - Start the development server with: `npm run dev`.