diff --git a/crates/puffin-cli/src/requirements.rs b/crates/puffin-cli/src/requirements.rs
index 20cd16dc2..bf02be8d4 100644
--- a/crates/puffin-cli/src/requirements.rs
+++ b/crates/puffin-cli/src/requirements.rs
@@ -82,13 +82,16 @@ impl RequirementsSpecification {
                             // Include any optional dependencies specified in `extras`
                             project.optional_dependencies.into_iter().flat_map(
                                 |optional_dependencies| {
-                                    extras.iter().flat_map(move |extra| {
-                                        optional_dependencies
-                                            .get(extra.as_ref())
-                                            .cloned()
-                                            // undefined extra requests are ignored silently
-                                            .unwrap_or_default()
-                                    })
+                                    optional_dependencies
+                                        .iter()
+                                        .flat_map(|(name, requirements)| {
+                                            if extras.contains(&ExtraName::normalize(name)) {
+                                                requirements.clone()
+                                            } else {
+                                                vec![]
+                                            }
+                                        })
+                                        .collect::<Vec<Requirement>>()
                                 },
                             ),
                         )
diff --git a/crates/puffin-cli/tests/pip_compile.rs b/crates/puffin-cli/tests/pip_compile.rs
index b02235d94..3e27f206c 100644
--- a/crates/puffin-cli/tests/pip_compile.rs
+++ b/crates/puffin-cli/tests/pip_compile.rs
@@ -280,3 +280,56 @@ optional-dependencies.foo = [
 
     Ok(())
 }
+
+/// Resolve a package from an extra with unnormalized names in a `pyproject.toml` file.
+#[test]
+fn compile_pyproject_toml_extra_name_normalization() -> Result<()> {
+    let temp_dir = assert_fs::TempDir::new()?;
+    let cache_dir = assert_fs::TempDir::new()?;
+    let venv = temp_dir.child(".venv");
+
+    Command::new(get_cargo_bin(BIN_NAME))
+        .arg("venv")
+        .arg(venv.as_os_str())
+        .arg("--cache-dir")
+        .arg(cache_dir.path())
+        .current_dir(&temp_dir)
+        .assert()
+        .success();
+    venv.assert(predicates::path::is_dir());
+
+    let pyproject_toml = temp_dir.child("pyproject.toml");
+    pyproject_toml.touch()?;
+    pyproject_toml.write_str(
+        r#"[build-system]
+requires = ["setuptools", "wheel"]
+
+[project]
+name = "project"
+dependencies = []
+optional-dependencies."FrIeNdLy-._.-bArD" = [
+    "django==5.0b1",
+]
+"#,
+    )?;
+
+    insta::with_settings!({
+        filters => vec![
+            (r"\d+(ms|s)", "[TIME]"),
+            (r"#    .* pip-compile", "#    [BIN_PATH] pip-compile"),
+            (r"--cache-dir .*", "--cache-dir [CACHE_DIR]"),
+        ]
+    }, {
+        assert_cmd_snapshot!(Command::new(get_cargo_bin(BIN_NAME))
+            .arg("pip-compile")
+            .arg("pyproject.toml")
+            .arg("--extra")
+            .arg("FRiENDlY-...-_-BARd")
+            .arg("--cache-dir")
+            .arg(cache_dir.path())
+            .env("VIRTUAL_ENV", venv.as_os_str())
+            .current_dir(&temp_dir));
+    });
+
+    Ok(())
+}
diff --git a/crates/puffin-cli/tests/snapshots/pip_compile__compile_pyproject_toml_extra_name_normalization.snap b/crates/puffin-cli/tests/snapshots/pip_compile__compile_pyproject_toml_extra_name_normalization.snap
new file mode 100644
index 000000000..5eac4f49f
--- /dev/null
+++ b/crates/puffin-cli/tests/snapshots/pip_compile__compile_pyproject_toml_extra_name_normalization.snap
@@ -0,0 +1,28 @@
+---
+source: crates/puffin-cli/tests/pip_compile.rs
+info:
+  program: puffin
+  args:
+    - pip-compile
+    - pyproject.toml
+    - "--extra"
+    - FRiENDlY-...-_-BARd
+    - "--cache-dir"
+    - /var/folders/bc/qlsk3t6x7c9fhhbvvcg68k9c0000gp/T/.tmpFyLXQn
+  env:
+    VIRTUAL_ENV: /var/folders/bc/qlsk3t6x7c9fhhbvvcg68k9c0000gp/T/.tmpxfZatv/.venv
+---
+success: true
+exit_code: 0
+----- stdout -----
+# This file was autogenerated by Puffin v0.0.1 via the following command:
+#    [BIN_PATH] pip-compile pyproject.toml --extra FRiENDlY-...-_-BARd --cache-dir [CACHE_DIR]
+asgiref==3.7.2
+    # via django
+django==5.0b1
+sqlparse==0.4.4
+    # via django
+
+----- stderr -----
+Resolved 3 packages in [TIME]
+
diff --git a/crates/puffin-package/src/extra_name.rs b/crates/puffin-package/src/extra_name.rs
index 920996127..3c3a38510 100644
--- a/crates/puffin-package/src/extra_name.rs
+++ b/crates/puffin-package/src/extra_name.rs
@@ -22,6 +22,9 @@ impl Display for ExtraName {
 static NAME_NORMALIZE: Lazy<Regex> = Lazy::new(|| Regex::new(r"[-_.]+").unwrap());
 
 impl ExtraName {
+    /// Collapses any run of the characters `-`, `_` and `.` down to a single `-`.
+    /// Ex) "---", ".", and "__" all get converted to just "."
+    ///
     /// See: <https://peps.python.org/pep-0685/#specification/>
     ///      <https://packaging.python.org/en/latest/specifications/name-normalization/>
     pub fn normalize(name: impl AsRef<str>) -> Self {