diff --git a/crates/red_knot_project/Cargo.toml b/crates/red_knot_project/Cargo.toml
index 43e1b2d190d8b..ea31f99f79a36 100644
--- a/crates/red_knot_project/Cargo.toml
+++ b/crates/red_knot_project/Cargo.toml
@@ -13,7 +13,7 @@ license.workspace = true
 
 [dependencies]
 ruff_cache = { workspace = true }
-ruff_db = { workspace = true, features = ["os", "cache", "serde"] }
+ruff_db = { workspace = true, features = ["cache", "serde"] }
 ruff_macros = { workspace = true }
 ruff_python_ast = { workspace = true, features = ["serde"] }
 ruff_text_size = { workspace = true }
diff --git a/crates/red_knot_python_semantic/Cargo.toml b/crates/red_knot_python_semantic/Cargo.toml
index cafd00e9c050b..47847e8307cc8 100644
--- a/crates/red_knot_python_semantic/Cargo.toml
+++ b/crates/red_knot_python_semantic/Cargo.toml
@@ -44,7 +44,7 @@ test-case = { workspace = true }
 memchr = { workspace = true }
 
 [dev-dependencies]
-ruff_db = { workspace = true, features = ["os", "testing"] }
+ruff_db = { workspace = true, features = ["testing"] }
 ruff_python_parser = { workspace = true }
 red_knot_test = { workspace = true }
 red_knot_vendored = { workspace = true }
diff --git a/crates/red_knot_server/Cargo.toml b/crates/red_knot_server/Cargo.toml
index 87e8126b8cd03..f14aa19350910 100644
--- a/crates/red_knot_server/Cargo.toml
+++ b/crates/red_knot_server/Cargo.toml
@@ -12,7 +12,7 @@ license = { workspace = true }
 
 [dependencies]
 red_knot_project = { workspace = true }
-ruff_db = { workspace = true }
+ruff_db = { workspace = true, features = ["os"] }
 ruff_notebook = { workspace = true }
 ruff_python_ast = { workspace = true }
 ruff_source_file = { workspace = true }
diff --git a/crates/red_knot_wasm/Cargo.toml b/crates/red_knot_wasm/Cargo.toml
index d6363f144695c..7cf08388348a2 100644
--- a/crates/red_knot_wasm/Cargo.toml
+++ b/crates/red_knot_wasm/Cargo.toml
@@ -22,7 +22,7 @@ default = ["console_error_panic_hook"]
 red_knot_python_semantic = { workspace = true }
 red_knot_project = { workspace = true, default-features = false, features = ["deflate"] }
 
-ruff_db = { workspace = true, features = [] }
+ruff_db = { workspace = true, default-features = false, features = [] }
 ruff_notebook = { workspace = true }
 
 console_error_panic_hook = { workspace = true, optional = true }
diff --git a/crates/ruff_db/Cargo.toml b/crates/ruff_db/Cargo.toml
index ec39450bc9f79..d771fd8a8a7c1 100644
--- a/crates/ruff_db/Cargo.toml
+++ b/crates/ruff_db/Cargo.toml
@@ -25,7 +25,6 @@ colored = { workspace = true }
 countme = { workspace = true }
 dashmap = { workspace = true }
 dunce = { workspace = true }
-etcetera = { workspace = true, optional = true }
 filetime = { workspace = true }
 glob = { workspace = true }
 ignore = { workspace = true, optional = true }
@@ -44,14 +43,16 @@ zip = { workspace = true }
 [target.'cfg(target_arch="wasm32")'.dependencies]
 web-time = { version = "1.1.0" }
 
+[target.'cfg(not(target_arch="wasm32"))'.dependencies]
+etcetera = { workspace = true, optional = true }
+
 [dev-dependencies]
 insta = { workspace = true }
 tempfile = { workspace = true }
 
 [features]
-default = ["os"]
 cache = ["ruff_cache"]
-os = ["ignore", "etcetera"]
+os = ["ignore", "dep:etcetera"]
 serde = ["dep:serde", "camino/serde1"]
 # Exposes testing utilities.
 testing = ["tracing-subscriber", "tracing-tree"]
diff --git a/crates/ruff_db/src/system/os.rs b/crates/ruff_db/src/system/os.rs
index c3370515c65c5..df752d85a1f45 100644
--- a/crates/ruff_db/src/system/os.rs
+++ b/crates/ruff_db/src/system/os.rs
@@ -1,7 +1,6 @@
 use std::sync::Arc;
 use std::{any::Any, path::PathBuf};
 
-use etcetera::BaseStrategy as _;
 use filetime::FileTime;
 
 use ruff_notebook::{Notebook, NotebookError};
@@ -99,11 +98,21 @@ impl System for OsSystem {
         &self.inner.cwd
     }
 
+    #[cfg(not(target_arch = "wasm32"))]
     fn user_config_directory(&self) -> Option<SystemPathBuf> {
+        use etcetera::BaseStrategy as _;
+
         let strategy = etcetera::base_strategy::choose_base_strategy().ok()?;
         SystemPathBuf::from_path_buf(strategy.config_dir()).ok()
     }
 
+    // TODO: Remove this feature gating once `ruff_wasm` no longer depends on `ruff_db` with the
+    // Os feature enabled.
+    #[cfg(target_arch = "wasm32")]
+    fn user_config_directory(&self) -> Option<SystemPathBuf> {
+        None
+    }
+
     /// Creates a builder to recursively walk `path`.
     ///
     /// The walker ignores files according to [`ignore::WalkBuilder::standard_filters`]
diff --git a/crates/ruff_db/src/system/test.rs b/crates/ruff_db/src/system/test.rs
index 1a79d01679312..14f7f2d0b09c1 100644
--- a/crates/ruff_db/src/system/test.rs
+++ b/crates/ruff_db/src/system/test.rs
@@ -26,7 +26,7 @@ pub struct TestSystem {
 }
 
 impl TestSystem {
-    /// Returns the [`InMemorySystem`].
+    /// Returns the `InMemorySystem`.
     ///
     /// ## Panics
     /// If this test db isn't the in memory system.
@@ -35,7 +35,7 @@ impl TestSystem {
             .expect("The test db is not using a memory file system")
     }
 
-    /// Returns the [`InMemorySystem`] or `None` if the test system is using an other underlying system.
+    /// Returns the `InMemorySystem` or `None` if the test system is using an other underlying system.
     pub fn as_in_memory(&self) -> Option<&InMemorySystem> {
         self.system().as_any().downcast_ref::<InMemorySystem>()
     }