diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 916edea..5292056 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -8,16 +8,53 @@ on:
   pull_request:
 
 jobs:
-  test:
+  test-sketch:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
       - uses: erlef/setup-beam@v1
         with:
-          otp-version: "26.0.2"
-          gleam-version: "1.0.0"
-          rebar3-version: "3"
+          otp-version: '26.0.2'
+          gleam-version: '1.4.1'
+          rebar3-version: '3'
           # elixir-version: "1.15.4"
       - run: gleam deps download
+        working-directory: sketch
       - run: gleam test
+        working-directory: sketch
       - run: gleam format --check src test
+        working-directory: sketch
+
+  test-sketch-css:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: erlef/setup-beam@v1
+        with:
+          otp-version: '26.0.2'
+          gleam-version: '1.4.1'
+          rebar3-version: '3'
+          # elixir-version: "1.15.4"
+      - run: gleam deps download
+        working-directory: sketch_css
+      - run: gleam test
+        working-directory: sketch_css
+      - run: gleam format --check src test
+        working-directory: sketch_css
+
+  test-sketch-lustr:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: erlef/setup-beam@v1
+        with:
+          otp-version: '26.0.2'
+          gleam-version: '1.4.1'
+          rebar3-version: '3'
+          # elixir-version: "1.15.4"
+      - run: gleam deps download
+        working-directory: sketch_lustre
+      - run: gleam test
+        working-directory: sketch_lustre
+      - run: gleam format --check src test
+        working-directory: sketch_lustre
diff --git a/e2e/shared_view/src/shared_view.gleam b/e2e/shared_view/src/shared_view.gleam
index 1c7fd5e..612f883 100644
--- a/e2e/shared_view/src/shared_view.gleam
+++ b/e2e/shared_view/src/shared_view.gleam
@@ -17,10 +17,8 @@ pub type Msg {
 }
 
 /// Defines the standard app, used everywhere in Lustre applications.
-/// For cross-technologies applications, only persistent cache can be used,
-/// because BEAM does not support ephemeral cache at the moment.
 pub fn app() {
-  let assert Ok(cache) = sketch.cache(strategy: sketch.Persistent)
+  let assert Ok(cache) = sketch.cache(strategy: sketch.Ephemeral)
   sketch_lustre.node()
   |> sketch_lustre.compose(view, cache)
   |> lustre.simple(fn(_) { 0 }, update, _)
diff --git a/e2e/ssr/manifest.toml b/e2e/ssr/manifest.toml
index 9f0b92c..1fbc2cc 100644
--- a/e2e/ssr/manifest.toml
+++ b/e2e/ssr/manifest.toml
@@ -16,15 +16,14 @@ packages = [
   { name = "gramps", version = "2.0.3", build_tools = ["gleam"], requirements = ["gleam_crypto", "gleam_erlang", "gleam_http", "gleam_stdlib"], otp_app = "gramps", source = "hex", outer_checksum = "3CCAA6E081225180D95C79679D383BBF51C8D1FDC1B84DA1DA444F628C373793" },
   { name = "hpack_erl", version = "0.3.0", build_tools = ["rebar3"], requirements = [], otp_app = "hpack", source = "hex", outer_checksum = "D6137D7079169D8C485C6962DFE261AF5B9EF60FBC557344511C1E65E3D95FB0" },
   { name = "logging", version = "1.3.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "logging", source = "hex", outer_checksum = "1098FBF10B54B44C2C7FDF0B01C1253CAFACDACABEFB4B0D027803246753E06D" },
-  { name = "lustre", version = "4.3.1", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_json", "gleam_otp", "gleam_stdlib"], otp_app = "lustre", source = "hex", outer_checksum = "A0010C17CE8C847A2B979CE9FE68FB94AE9D75247D1173594C10B7C2FD3C83F2" },
+  { name = "lustre", version = "4.3.2", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_json", "gleam_otp", "gleam_stdlib"], otp_app = "lustre", source = "hex", outer_checksum = "7F4CE2DB524A882F97C94AA3D320986B6CAC415146D5F98DE4782E1B0B59098F" },
   { name = "mist", version = "1.2.0", build_tools = ["gleam"], requirements = ["birl", "gleam_erlang", "gleam_http", "gleam_otp", "gleam_stdlib", "glisten", "gramps", "hpack_erl", "logging"], otp_app = "mist", source = "hex", outer_checksum = "109B4D64E68C104CC23BB3CC5441ECD479DD7444889DA01113B75C6AF0F0E17B" },
-  { name = "plinth", version = "0.4.10", build_tools = ["gleam"], requirements = ["conversation", "gleam_javascript", "gleam_json", "gleam_stdlib"], otp_app = "plinth", source = "hex", outer_checksum = "01561989B292CEF20C864B42E9A32FD15F3F3E46E7B0A2142727A3C556B16EF3" },
+  { name = "plinth", version = "0.4.11", build_tools = ["gleam"], requirements = ["conversation", "gleam_javascript", "gleam_json", "gleam_stdlib"], otp_app = "plinth", source = "hex", outer_checksum = "698B53538B02B261ABF30203F0B487B9C3BE2A1B40E858176ED0918AA1B61965" },
   { name = "ranger", version = "1.2.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "ranger", source = "hex", outer_checksum = "1566C272B1D141B3BBA38B25CB761EF56E312E79EC0E2DFD4D3C19FB0CC1F98C" },
   { name = "shared_view", version = "1.0.0", build_tools = ["gleam"], requirements = ["gleam_stdlib", "lustre", "sketch", "sketch_lustre"], source = "local", path = "../shared_view" },
-  { name = "sketch", version = "2.3.0", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_otp", "gleam_stdlib"], source = "local", path = "../../sketch" },
+  { name = "sketch", version = "3.0.0", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_otp", "gleam_stdlib"], source = "local", path = "../../sketch" },
   { name = "sketch_lustre", version = "1.0.0", build_tools = ["gleam"], requirements = ["gleam_stdlib", "lustre", "plinth", "sketch"], source = "local", path = "../../sketch_lustre" },
   { name = "thoas", version = "1.2.1", build_tools = ["rebar3"], requirements = [], otp_app = "thoas", source = "hex", outer_checksum = "E38697EDFFD6E91BD12CEA41B155115282630075C2A727E7A6B2947F5408B86A" },
-  { name = "xxhash", version = "0.3.1", build_tools = ["mix"], requirements = [], otp_app = "xxhash", source = "hex", outer_checksum = "14FEF02F550C1B393DE52912F7EF4CE53B5749C63DB70FFDC6582474E625513C" },
 ]
 
 [requirements]
diff --git a/e2e/ssr/src/ssr.gleam b/e2e/ssr/src/ssr.gleam
index 376002f..5b5f42e 100644
--- a/e2e/ssr/src/ssr.gleam
+++ b/e2e/ssr/src/ssr.gleam
@@ -8,7 +8,7 @@ import sketch
 import sketch/lustre as sketch_lustre
 
 pub fn main() {
-  let assert Ok(cache) = sketch.cache(strategy: sketch.Persistent)
+  let assert Ok(cache) = sketch.cache(strategy: sketch.Ephemeral)
   let assert Ok(_) =
     fn(_) { greet(cache) }
     |> mist.new()
diff --git a/sketch/README.md b/sketch/README.md
index 871fce4..665618b 100644
--- a/sketch/README.md
+++ b/sketch/README.md
@@ -60,8 +60,7 @@ import sketch
 import sketch/lustre as sketch_lustre
 
 pub fn main() {
-  // Initialise the cache. Two strategies can be used in browser, only one
-  // on server-side.
+  // Initialise the cache. Two strategies can be used. Ephemeral caches are designed as throw-away caches.
   let assert Ok(cache) = sketch.cache(strategy: sketch.Ephemeral)
   // Select the output of the generated stylesheet.
   sketch_lustre.node()
diff --git a/sketch/src/sketch.gleam b/sketch/src/sketch.gleam
index aaa582f..3c66ff7 100644
--- a/sketch/src/sketch.gleam
+++ b/sketch/src/sketch.gleam
@@ -4,6 +4,7 @@
 import gleam/float
 import gleam/int
 import gleam/list
+import gleam/pair
 import gleam/result
 import gleam/string
 import sketch/internals/cache/setup as cache
@@ -33,33 +34,22 @@ pub fn class(styles: List(style.Style)) -> Class {
   style.class(styles)
 }
 
-@target(erlang)
 /// Render the content in the cache in proper CSS stylesheet.
 pub fn render(cache: Cache) {
-  let assert BeamCache(cache) = cache
-  cache.render(cache)
-}
-
-@target(javascript)
-pub fn render(cache: Cache) {
-  let assert JsCache(cache) = cache
-  style.render(cache)
+  case cache {
+    BeamCache(cache:) -> cache.render(cache)
+    JsCache(cache:) -> style.render(cache)
+  }
 }
 
-@target(javascript)
 /// Convert a `Class` to its proper class name, to use it anywhere in your
 /// application. It can have the form `class1` or `class1 class2` in case of
 /// classes composition.
 pub fn class_name(class: Class, cache: Cache) -> #(Cache, String) {
-  let assert JsCache(cache) = cache
-  let #(cache, class_name) = style.class_name(class, cache)
-  #(JsCache(cache), class_name)
-}
-
-@target(erlang)
-pub fn class_name(class: Class, cache: Cache) -> #(Cache, String) {
-  let assert BeamCache(cache) = cache
-  #(BeamCache(cache), cache.class_name(class, cache))
+  case cache {
+    JsCache(c) -> style.class_name(class, c) |> pair.map_first(JsCache)
+    BeamCache(c) -> cache.class_name(class, c) |> pair.map_first(BeamCache)
+  }
 }
 
 /// Strategy for the Cache. Two strategies are available as of now: ephemeral
@@ -67,7 +57,7 @@ pub fn class_name(class: Class, cache: Cache) -> #(Cache, String) {
 /// generation wil rely on hashing function. It means two class names will be
 /// identical if their content are identical.
 /// In the second case, the cache is persistent, meaning it will keep the
-/// memories of the generated classes. On BEAM, only Persistent is allowed.
+/// memories of the generated classes.
 pub type Strategy {
   Ephemeral
   Persistent
@@ -76,6 +66,7 @@ pub type Strategy {
 @target(javascript)
 /// Create a cache, managing the styles. You can instanciate as much cache as
 /// you want, if you need to manage different stylesheets.
+/// Instanciating an `Ephemeral` _always_ succeed.
 pub fn cache(strategy strategy: Strategy) {
   Ok(case strategy {
     Ephemeral -> JsCache(style.ephemeral())
@@ -84,8 +75,13 @@ pub fn cache(strategy strategy: Strategy) {
 }
 
 @target(erlang)
-pub fn cache(strategy _strategy: Strategy) {
-  cache.persistent() |> result.map(BeamCache)
+pub fn cache(strategy strategy: Strategy) {
+  case strategy {
+    Ephemeral -> Ok(BeamCache(cache.ephemeral()))
+    Persistent ->
+      cache.persistent()
+      |> result.map(BeamCache)
+  }
 }
 
 // Properties
diff --git a/sketch/src/sketch/internals/cache/setup.gleam b/sketch/src/sketch/internals/cache/setup.gleam
index 76ba02c..d9bf217 100644
--- a/sketch/src/sketch/internals/cache/setup.gleam
+++ b/sketch/src/sketch/internals/cache/setup.gleam
@@ -4,34 +4,53 @@ import gleam/bool
 import gleam/erlang/process.{type Subject}
 import gleam/list
 import gleam/otp/actor
+import gleam/pair
 import gleam/result
 import sketch/internals/cache/state
 import sketch/internals/style
 
 /// Manages the styles. Can be instanciated with [`create_cache`](#create_cache).
 pub opaque type Cache {
-  Cache(subject: Subject(state.Request))
+  PersistentCache(subject: Subject(state.Request))
+  EphemeralCache(cache: style.Cache)
+}
+
+@target(erlang)
+pub fn ephemeral() {
+  EphemeralCache(style.ephemeral())
 }
 
 @target(erlang)
 pub fn persistent() -> Result(Cache, Nil) {
   let assert Ok(subject) = actor.start(style.persistent(), state.loop)
-  Ok(Cache(subject))
+  Ok(PersistentCache(subject))
 }
 
 @target(erlang)
 pub fn render(cache: Cache) -> String {
-  let Cache(subject) = cache
-  process.try_call(subject, state.Render, 1000)
-  |> result.nil_error()
-  |> result.unwrap("")
+  case cache {
+    EphemeralCache(cache:) -> style.render(cache)
+    PersistentCache(subject:) -> {
+      process.try_call(subject, state.Render, 1000)
+      |> result.nil_error()
+      |> result.unwrap("")
+    }
+  }
 }
 
 @target(erlang)
-pub fn class_name(class: style.Class, cache: Cache) -> String {
-  let style.Class(string_representation: _, content: c) = class
-  let Cache(subject) = cache
-  use <- bool.guard(when: list.is_empty(c), return: "")
-  process.try_call(subject, state.Fetch(class, _), within: 100)
-  |> result.unwrap("")
+pub fn class_name(class: style.Class, cache: Cache) -> #(Cache, String) {
+  case cache {
+    EphemeralCache(cache:) -> {
+      let #(cache, class_name) = style.class_name(class, cache)
+      #(EphemeralCache(cache:), class_name)
+    }
+    PersistentCache(subject:) -> {
+      let style.Class(string_representation: _, content: c) = class
+      use <- bool.guard(when: list.is_empty(c), return: #(cache, ""))
+      process.try_call(subject, state.Fetch(class, _), within: 100)
+      |> result.unwrap("")
+      |> pair.new(cache, _)
+    }
+  }
 }
diff --git a/sketch/src/sketch/internals/cache/state.gleam b/sketch/src/sketch/internals/cache/state.gleam
index e536777..bbc4930 100644
--- a/sketch/src/sketch/internals/cache/state.gleam
+++ b/sketch/src/sketch/internals/cache/state.gleam
@@ -2,7 +2,6 @@
 
 import gleam/erlang/process.{type Subject}
 import gleam/otp/actor
-import gleam/string
 import sketch/internals/style
 
 pub type Request {
diff --git a/sketch/src/sketch/internals/style.gleam b/sketch/src/sketch/internals/style.gleam
index 237c033..980ca39 100644
--- a/sketch/src/sketch/internals/style.gleam
+++ b/sketch/src/sketch/internals/style.gleam
@@ -8,10 +8,9 @@ import gleam/string
 import sketch/internals/class
 import sketch/internals/string as sketch_string
 
+@external(erlang, "erlang", "phash2")
 @external(javascript, "../../xxhash.ffi.mjs", "xxHash32")
-fn xx_hash32(content: String) -> Int {
-  0
-}
+fn xx_hash32(content: String) -> Int
 
 pub type Class {
   Class(string_representation: String, content: List(Style))