diff --git a/Cargo.lock b/Cargo.lock
index 8c62525df61dc..4e30bcbc77e3b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4784,7 +4784,6 @@ name = "uv-distribution"
 version = "0.0.1"
 dependencies = [
  "anyhow",
- "cache-key",
  "distribution-filename",
  "distribution-types",
  "fs-err",
diff --git a/crates/install-wheel-rs/Cargo.toml b/crates/install-wheel-rs/Cargo.toml
index a52045ba2e959..43feb43590554 100644
--- a/crates/install-wheel-rs/Cargo.toml
+++ b/crates/install-wheel-rs/Cargo.toml
@@ -2,7 +2,7 @@
 name = "install-wheel-rs"
 version = "0.0.1"
 publish = false
-description = "Takes a wheel and installs it, either in a venv or for monotrail"
+description = "Takes a wheel and installs it."
 keywords = ["wheel", "python"]
 
 edition = { workspace = true }
diff --git a/crates/install-wheel-rs/Readme.md b/crates/install-wheel-rs/Readme.md
deleted file mode 100644
index f339a109b33a4..0000000000000
--- a/crates/install-wheel-rs/Readme.md
+++ /dev/null
@@ -1,3 +0,0 @@
-# install-wheel-rs
-
-Reimplementation of wheel installing in Rust.
diff --git a/crates/uv-cache-info/src/cache_info.rs b/crates/uv-cache-info/src/cache_info.rs
index c0e92c056c493..544dc05d91798 100644
--- a/crates/uv-cache-info/src/cache_info.rs
+++ b/crates/uv-cache-info/src/cache_info.rs
@@ -6,15 +6,23 @@ use std::cmp::max;
 use std::io;
 use std::path::{Path, PathBuf};
 
+/// The information used to determine whether a built distribution is up-to-date, based on the
+/// timestamps of relevant files, the current commit of a repository, etc.
 #[derive(Default, Debug, Clone, Hash, PartialEq, Eq, serde::Deserialize, serde::Serialize)]
 #[serde(rename_all = "kebab-case")]
 #[serde(try_from = "CacheInfoWire")]
 pub struct CacheInfo {
+    /// The timestamp of the most recent `ctime` of any relevant files, at the time of the build.
+    /// The timestamp will typically be the maximum of the `ctime` values of the `pyproject.toml`,
+    /// `setup.py`, and `setup.cfg` files, if they exist; however, users can provide additional
+    /// files to timestamp via the `cache-keys` field.
     timestamp: Option<Timestamp>,
+    /// The commit at which the distribution was built.
     commit: Option<Commit>,
 }
 
 impl CacheInfo {
+    /// Return the [`CacheInfo`] for a given timestamp.
     pub fn from_timestamp(timestamp: Timestamp) -> Self {
         Self {
             timestamp: Some(timestamp),
@@ -22,6 +30,7 @@ impl CacheInfo {
         }
     }
 
+    /// Compute the cache info for a given path, which may be a file or a directory.
     pub fn from_path(path: &Path) -> io::Result<Self> {
         let metadata = fs_err::metadata(path)?;
         if metadata.is_file() {
@@ -31,6 +40,7 @@ impl CacheInfo {
         }
     }
 
+    /// Compute the cache info for a given directory.
     pub fn from_directory(directory: &Path) -> io::Result<Self> {
         let mut commit = None;
 
@@ -103,6 +113,8 @@ impl CacheInfo {
         Ok(Self { timestamp, commit })
     }
 
+    /// Compute the cache info for a given file, assumed to be a binary or source distribution
+    /// represented as (e.g.) a `.whl` or `.tar.gz` archive.
     pub fn from_file(path: impl AsRef<Path>) -> Result<Self, io::Error> {
         let metadata = fs_err::metadata(path.as_ref())?;
         let timestamp = Timestamp::from_metadata(&metadata);
@@ -126,7 +138,10 @@ struct TimestampCommit {
 #[derive(Debug, serde::Deserialize)]
 #[serde(untagged)]
 enum CacheInfoWire {
+    /// For backwards-compatibility, enable deserializing [`CacheInfo`] structs that are solely
+    /// represented by a timestamp.
     Timestamp(Timestamp),
+    /// A [`CacheInfo`] struct that includes both a timestamp and a commit.
     TimestampCommit(TimestampCommit),
 }
 
diff --git a/crates/uv-cache-info/src/commit_info.rs b/crates/uv-cache-info/src/commit_info.rs
index de0b620b8d74c..533b54a6fcf14 100644
--- a/crates/uv-cache-info/src/commit_info.rs
+++ b/crates/uv-cache-info/src/commit_info.rs
@@ -1,6 +1,6 @@
 use std::path::{Path, PathBuf};
 
-/// The current commit for a repository.
+/// The current commit for a repository (i.e., a 40-character hexadecimal string).
 #[derive(Default, Debug, Clone, Hash, PartialEq, Eq, serde::Deserialize, serde::Serialize)]
 pub(crate) struct Commit(String);
 
diff --git a/crates/uv-dispatch/src/lib.rs b/crates/uv-dispatch/src/lib.rs
index 2b66b9ab45fd5..bbd71ab1dd1f1 100644
--- a/crates/uv-dispatch/src/lib.rs
+++ b/crates/uv-dispatch/src/lib.rs
@@ -214,7 +214,6 @@ impl<'a> BuildContext for BuildDispatch<'a> {
             &BuildOptions::default(),
             self.hasher,
             self.index_locations,
-            self.config_settings,
             self.cache(),
             venv,
             &markers,
diff --git a/crates/uv-distribution/Cargo.toml b/crates/uv-distribution/Cargo.toml
index 26d445d8a211b..4b798c0253796 100644
--- a/crates/uv-distribution/Cargo.toml
+++ b/crates/uv-distribution/Cargo.toml
@@ -13,7 +13,6 @@ license = { workspace = true }
 workspace = true
 
 [dependencies]
-cache-key = { workspace = true }
 distribution-filename = { workspace = true }
 distribution-types = { workspace = true }
 install-wheel-rs = { workspace = true }
diff --git a/crates/uv-distribution/src/index/built_wheel_index.rs b/crates/uv-distribution/src/index/built_wheel_index.rs
index 1f5caf94ce4bf..a7e83f7ecc7f8 100644
--- a/crates/uv-distribution/src/index/built_wheel_index.rs
+++ b/crates/uv-distribution/src/index/built_wheel_index.rs
@@ -7,7 +7,6 @@ use distribution_types::{
 use platform_tags::Tags;
 use uv_cache::{Cache, CacheBucket, CacheShard, WheelCache};
 use uv_cache_info::CacheInfo;
-use uv_configuration::ConfigSettings;
 use uv_fs::symlinks;
 use uv_types::HashStrategy;
 
@@ -17,22 +16,15 @@ pub struct BuiltWheelIndex<'a> {
     cache: &'a Cache,
     tags: &'a Tags,
     hasher: &'a HashStrategy,
-    build_configuration: &'a ConfigSettings,
 }
 
 impl<'a> BuiltWheelIndex<'a> {
     /// Initialize an index of built distributions.
-    pub fn new(
-        cache: &'a Cache,
-        tags: &'a Tags,
-        hasher: &'a HashStrategy,
-        build_configuration: &'a ConfigSettings,
-    ) -> Self {
+    pub fn new(cache: &'a Cache, tags: &'a Tags, hasher: &'a HashStrategy) -> Self {
         Self {
             cache,
             tags,
             hasher,
-            build_configuration,
         }
     }
 
@@ -61,13 +53,6 @@ impl<'a> BuiltWheelIndex<'a> {
 
         let cache_shard = cache_shard.shard(revision.id());
 
-        // If there are build settings, we need to scope to a cache shard.
-        let cache_shard = if self.build_configuration.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(self.build_configuration))
-        };
-
         Ok(self.find(&cache_shard))
     }
     /// Return the most compatible [`CachedWheel`] for a given source distribution at a local path.
@@ -98,13 +83,6 @@ impl<'a> BuiltWheelIndex<'a> {
 
         let cache_shard = cache_shard.shard(revision.id());
 
-        // If there are build settings, we need to scope to a cache shard.
-        let cache_shard = if self.build_configuration.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(self.build_configuration))
-        };
-
         Ok(self
             .find(&cache_shard)
             .map(|wheel| wheel.with_cache_info(cache_info)))
@@ -147,13 +125,6 @@ impl<'a> BuiltWheelIndex<'a> {
 
         let cache_shard = cache_shard.shard(revision.id());
 
-        // If there are build settings, we need to scope to a cache shard.
-        let cache_shard = if self.build_configuration.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(self.build_configuration))
-        };
-
         Ok(self
             .find(&cache_shard)
             .map(|wheel| wheel.with_cache_info(cache_info)))
@@ -173,13 +144,6 @@ impl<'a> BuiltWheelIndex<'a> {
             WheelCache::Git(&source_dist.url, &git_sha.to_short_string()).root(),
         );
 
-        // If there are build settings, we need to scope to a cache shard.
-        let cache_shard = if self.build_configuration.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(self.build_configuration))
-        };
-
         self.find(&cache_shard)
     }
 
diff --git a/crates/uv-distribution/src/source/mod.rs b/crates/uv-distribution/src/source/mod.rs
index cf908f2963aca..483e4619b5873 100644
--- a/crates/uv-distribution/src/source/mod.rs
+++ b/crates/uv-distribution/src/source/mod.rs
@@ -426,14 +426,6 @@ impl<'a, T: BuildContext> SourceDistributionBuilder<'a, T> {
         // freshness, since entries have to be fresher than the revision itself.
         let cache_shard = cache_shard.shard(revision.id());
 
-        // If there are build settings, we need to scope to a cache shard.
-        let config_settings = self.build_context.config_settings();
-        let cache_shard = if config_settings.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(config_settings))
-        };
-
         // If the cache contains a compatible wheel, return it.
         if let Some(built_wheel) = BuiltWheelMetadata::find_in_cache(tags, &cache_shard) {
             return Ok(built_wheel.with_hashes(revision.into_hashes()));
@@ -527,14 +519,6 @@ impl<'a, T: BuildContext> SourceDistributionBuilder<'a, T> {
             });
         }
 
-        // If there are build settings, we need to scope to a cache shard.
-        let config_settings = self.build_context.config_settings();
-        let cache_shard = if config_settings.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(config_settings))
-        };
-
         // Otherwise, we either need to build the metadata.
         // If the backend supports `prepare_metadata_for_build_wheel`, use it.
         if let Some(metadata) = self
@@ -687,14 +671,6 @@ impl<'a, T: BuildContext> SourceDistributionBuilder<'a, T> {
         // freshness, since entries have to be fresher than the revision itself.
         let cache_shard = cache_shard.shard(revision.id());
 
-        // If there are build settings, we need to scope to a cache shard.
-        let config_settings = self.build_context.config_settings();
-        let cache_shard = if config_settings.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(config_settings))
-        };
-
         // If the cache contains a compatible wheel, return it.
         if let Some(built_wheel) = BuiltWheelMetadata::find_in_cache(tags, &cache_shard) {
             return Ok(built_wheel);
@@ -805,14 +781,6 @@ impl<'a, T: BuildContext> SourceDistributionBuilder<'a, T> {
             });
         }
 
-        // If there are build settings, we need to scope to a cache shard.
-        let config_settings = self.build_context.config_settings();
-        let cache_shard = if config_settings.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(config_settings))
-        };
-
         // Otherwise, we need to build a wheel.
         let task = self
             .reporter
@@ -929,14 +897,6 @@ impl<'a, T: BuildContext> SourceDistributionBuilder<'a, T> {
         // freshness, since entries have to be fresher than the revision itself.
         let cache_shard = cache_shard.shard(revision.id());
 
-        // If there are build settings, we need to scope to a cache shard.
-        let config_settings = self.build_context.config_settings();
-        let cache_shard = if config_settings.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(config_settings))
-        };
-
         // If the cache contains a compatible wheel, return it.
         if let Some(built_wheel) = BuiltWheelMetadata::find_in_cache(tags, &cache_shard) {
             return Ok(built_wheel);
@@ -1060,14 +1020,6 @@ impl<'a, T: BuildContext> SourceDistributionBuilder<'a, T> {
             ));
         }
 
-        // If there are build settings, we need to scope to a cache shard.
-        let config_settings = self.build_context.config_settings();
-        let cache_shard = if config_settings.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(config_settings))
-        };
-
         // Otherwise, we need to build a wheel.
         let task = self
             .reporter
@@ -1179,14 +1131,6 @@ impl<'a, T: BuildContext> SourceDistributionBuilder<'a, T> {
 
         let _lock = lock_shard(&cache_shard).await?;
 
-        // If there are build settings, we need to scope to a cache shard.
-        let config_settings = self.build_context.config_settings();
-        let cache_shard = if config_settings.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(config_settings))
-        };
-
         // If the cache contains a compatible wheel, return it.
         if let Some(built_wheel) = BuiltWheelMetadata::find_in_cache(tags, &cache_shard) {
             return Ok(built_wheel);
@@ -1313,14 +1257,6 @@ impl<'a, T: BuildContext> SourceDistributionBuilder<'a, T> {
             ));
         }
 
-        // If there are build settings, we need to scope to a cache shard.
-        let config_settings = self.build_context.config_settings();
-        let cache_shard = if config_settings.is_empty() {
-            cache_shard
-        } else {
-            cache_shard.shard(cache_key::cache_digest(config_settings))
-        };
-
         // Otherwise, we need to build a wheel.
         let task = self
             .reporter
diff --git a/crates/uv-installer/src/plan.rs b/crates/uv-installer/src/plan.rs
index 26bcb051d4c6b..2c5c73d38cd43 100644
--- a/crates/uv-installer/src/plan.rs
+++ b/crates/uv-installer/src/plan.rs
@@ -15,7 +15,7 @@ use platform_tags::Tags;
 use pypi_types::{Requirement, RequirementSource, ResolverMarkerEnvironment};
 use uv_cache::{Cache, CacheBucket, WheelCache};
 use uv_cache_info::{CacheInfo, Timestamp};
-use uv_configuration::{BuildOptions, ConfigSettings, Reinstall};
+use uv_configuration::{BuildOptions, Reinstall};
 use uv_distribution::{
     BuiltWheelIndex, HttpArchivePointer, LocalArchivePointer, RegistryWheelIndex,
 };
@@ -57,7 +57,6 @@ impl<'a> Planner<'a> {
         build_options: &BuildOptions,
         hasher: &HashStrategy,
         index_locations: &IndexLocations,
-        config_settings: &ConfigSettings,
         cache: &Cache,
         venv: &PythonEnvironment,
         markers: &ResolverMarkerEnvironment,
@@ -65,7 +64,7 @@ impl<'a> Planner<'a> {
     ) -> Result<Plan> {
         // Index all the already-downloaded wheels in the cache.
         let mut registry_index = RegistryWheelIndex::new(cache, tags, index_locations, hasher);
-        let built_index = BuiltWheelIndex::new(cache, tags, hasher, config_settings);
+        let built_index = BuiltWheelIndex::new(cache, tags, hasher);
 
         let mut cached = vec![];
         let mut remote = vec![];
diff --git a/crates/uv/src/commands/pip/install.rs b/crates/uv/src/commands/pip/install.rs
index 4441c2ecc0249..7223c671e0d2d 100644
--- a/crates/uv/src/commands/pip/install.rs
+++ b/crates/uv/src/commands/pip/install.rs
@@ -407,7 +407,6 @@ pub(crate) async fn pip_install(
         link_mode,
         compile,
         &index_locations,
-        config_settings,
         &hasher,
         &markers,
         &tags,
diff --git a/crates/uv/src/commands/pip/operations.rs b/crates/uv/src/commands/pip/operations.rs
index 3663a8fe57a8f..9801290c4215b 100644
--- a/crates/uv/src/commands/pip/operations.rs
+++ b/crates/uv/src/commands/pip/operations.rs
@@ -21,8 +21,7 @@ use pypi_types::ResolverMarkerEnvironment;
 use uv_cache::Cache;
 use uv_client::{BaseClientBuilder, RegistryClient};
 use uv_configuration::{
-    BuildOptions, Concurrency, ConfigSettings, Constraints, ExtrasSpecification, Overrides,
-    Reinstall, Upgrade,
+    BuildOptions, Concurrency, Constraints, ExtrasSpecification, Overrides, Reinstall, Upgrade,
 };
 use uv_dispatch::BuildDispatch;
 use uv_distribution::DistributionDatabase;
@@ -350,7 +349,6 @@ pub(crate) async fn install(
     link_mode: LinkMode,
     compile: bool,
     index_urls: &IndexLocations,
-    config_settings: &ConfigSettings,
     hasher: &HashStrategy,
     markers: &ResolverMarkerEnvironment,
     tags: &Tags,
@@ -378,7 +376,6 @@ pub(crate) async fn install(
             build_options,
             hasher,
             index_urls,
-            config_settings,
             cache,
             venv,
             markers,
diff --git a/crates/uv/src/commands/pip/sync.rs b/crates/uv/src/commands/pip/sync.rs
index 4e1e102c9698f..383f5a880a872 100644
--- a/crates/uv/src/commands/pip/sync.rs
+++ b/crates/uv/src/commands/pip/sync.rs
@@ -359,7 +359,6 @@ pub(crate) async fn pip_sync(
         link_mode,
         compile,
         &index_locations,
-        config_settings,
         &hasher,
         &markers,
         &tags,
diff --git a/crates/uv/src/commands/project/mod.rs b/crates/uv/src/commands/project/mod.rs
index 20febff9c3c7c..8f5ed2dc5200e 100644
--- a/crates/uv/src/commands/project/mod.rs
+++ b/crates/uv/src/commands/project/mod.rs
@@ -807,7 +807,6 @@ pub(crate) async fn sync_environment(
         link_mode,
         compile_bytecode,
         index_locations,
-        config_setting,
         &hasher,
         &markers,
         tags,
@@ -1040,7 +1039,6 @@ pub(crate) async fn update_environment(
         *link_mode,
         *compile_bytecode,
         index_locations,
-        config_setting,
         &hasher,
         &markers,
         tags,
diff --git a/crates/uv/src/commands/project/sync.rs b/crates/uv/src/commands/project/sync.rs
index c177e55543aac..bedd907337021 100644
--- a/crates/uv/src/commands/project/sync.rs
+++ b/crates/uv/src/commands/project/sync.rs
@@ -304,7 +304,6 @@ pub(super) async fn do_sync(
         link_mode,
         compile_bytecode,
         index_locations,
-        config_setting,
         &hasher,
         &markers,
         tags,
diff --git a/crates/uv/tests/pip_install.rs b/crates/uv/tests/pip_install.rs
index 511461427bab6..de29a2923d015 100644
--- a/crates/uv/tests/pip_install.rs
+++ b/crates/uv/tests/pip_install.rs
@@ -2764,37 +2764,9 @@ fn config_settings() {
         .join("__editable___setuptools_editable_0_1_0_finder.py");
     assert!(finder.exists());
 
-    // Reinstalling with `--editable_mode=compat` should be a no-op; changes in build configuration
-    // don't invalidate the environment.
-    uv_snapshot!(context.filters(), context.pip_install()
-        .arg("-e")
-        .arg(context.workspace_root.join("scripts/packages/setuptools_editable"))
-        .arg("-C")
-        .arg("editable_mode=compat")
-        , @r###"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-
-    ----- stderr -----
-    Audited 1 package in [TIME]
-    "###
-    );
-
-    // Uninstall the package.
-    uv_snapshot!(context.filters(), context.pip_uninstall()
-        .arg("setuptools-editable"), @r###"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-
-    ----- stderr -----
-    Uninstalled 1 package in [TIME]
-     - setuptools-editable==0.1.0 (from file://[WORKSPACE]/scripts/packages/setuptools_editable)
-    "###);
+    // Install the editable package with `--editable_mode=compat`.
+    let context = TestContext::new("3.12");
 
-    // Install the editable package with `--editable_mode=compat`. We should ignore the cached
-    // build configuration and rebuild.
     uv_snapshot!(context.filters(), context.pip_install()
         .arg("-e")
         .arg(context.workspace_root.join("scripts/packages/setuptools_editable"))
@@ -2807,8 +2779,9 @@ fn config_settings() {
 
     ----- stderr -----
     Resolved 2 packages in [TIME]
-    Prepared 1 package in [TIME]
-    Installed 1 package in [TIME]
+    Prepared 2 packages in [TIME]
+    Installed 2 packages in [TIME]
+     + iniconfig==2.0.0
      + setuptools-editable==0.1.0 (from file://[WORKSPACE]/scripts/packages/setuptools_editable)
     "###
     );
@@ -2953,7 +2926,7 @@ requires-python = ">=3.8"
     "###
     );
 
-    // Re-installing should be a no-op.
+    // Installing again should be a no-op.
     uv_snapshot!(context.filters(), context.pip_install()
         .arg("--editable")
         .arg(editable_dir.path()), @r###"
@@ -3095,7 +3068,7 @@ requires-python = ">=3.8"
     "###
     );
 
-    // Re-installing should be a no-op.
+    // Installing again should be a no-op.
     uv_snapshot!(context.filters(), context.pip_install()
         .arg("example @ .")
         .current_dir(editable_dir.path()), @r###"
@@ -3186,7 +3159,7 @@ fn invalidate_path_on_cache_key() -> Result<()> {
     "###
     );
 
-    // Re-installing should be a no-op.
+    // Installing again should be a no-op.
     uv_snapshot!(context.filters(), context.pip_install()
         .arg("example @ .")
         .current_dir(editable_dir.path()), @r###"
@@ -3296,7 +3269,7 @@ fn invalidate_path_on_commit() -> Result<()> {
     "###
     );
 
-    // Re-installing should be a no-op.
+    // Installing again should be a no-op.
     uv_snapshot!(context.filters(), context.pip_install()
         .arg("example @ .")
         .current_dir(editable_dir.path()), @r###"
diff --git a/crates/uv/tests/pip_sync.rs b/crates/uv/tests/pip_sync.rs
index eceb189438557..791b0f2b1cf1a 100644
--- a/crates/uv/tests/pip_sync.rs
+++ b/crates/uv/tests/pip_sync.rs
@@ -3215,7 +3215,7 @@ requires-python = ">=3.8"
     "###
     );
 
-    // Re-installing should be a no-op.
+    // Installing again should be a no-op.
     uv_snapshot!(context.filters(), context.pip_sync()
         .arg("requirements.in"), @r###"
     success: true