diff --git a/.gitignore b/.gitignore
index 79d27d5bf..abcd6f2a8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,9 +9,6 @@ target/
 # MSVC Windows builds of rustc generate these, which store debugging information
 *.pdb
 
-# Use e.g. `--cache-dir cache-docker` to keep a cache across container invocations
-cache-*
-
 # Python tmp files
 __pycache__
 
diff --git a/Cargo.lock b/Cargo.lock
index 7a4d26f1f..6d16bfe49 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -391,6 +391,15 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a3e368af43e418a04d52505cf3dbc23dda4e3407ae2fa99fd0e4f308ce546acc"
 
+[[package]]
+name = "cache-key"
+version = "0.0.1"
+dependencies = [
+ "hex",
+ "seahash",
+ "url",
+]
+
 [[package]]
 name = "cachedir"
 version = "0.3.1"
@@ -847,11 +856,11 @@ name = "distribution-types"
 version = "0.0.1"
 dependencies = [
  "anyhow",
+ "cache-key",
  "distribution-filename",
  "fs-err",
  "pep440_rs 0.3.12",
  "pep508_rs",
- "puffin-cache",
  "puffin-git",
  "puffin-normalize",
  "pypi-types",
@@ -2291,15 +2300,14 @@ dependencies = [
 name = "puffin-cache"
 version = "0.0.1"
 dependencies = [
+ "cache-key",
  "cachedir",
  "clap",
  "directories",
  "fs-err",
- "hex",
  "puffin-fs",
  "puffin-normalize",
  "pypi-types",
- "seahash",
  "serde",
  "tempfile",
  "tracing",
@@ -2375,6 +2383,7 @@ dependencies = [
  "anyhow",
  "async_http_range_reader",
  "async_zip",
+ "cache-key",
  "distribution-filename",
  "distribution-types",
  "fs-err",
@@ -2483,6 +2492,7 @@ version = "0.0.1"
 dependencies = [
  "anyhow",
  "bytesize",
+ "cache-key",
  "distribution-filename",
  "distribution-types",
  "fs-err",
@@ -2541,12 +2551,12 @@ name = "puffin-git"
 version = "0.0.1"
 dependencies = [
  "anyhow",
+ "cache-key",
  "cargo-util",
  "git2",
  "glob",
  "hex",
  "once_cell",
- "puffin-cache",
  "rand",
  "reqwest",
  "serde",
@@ -2593,6 +2603,7 @@ dependencies = [
 name = "puffin-interpreter"
 version = "0.0.1"
 dependencies = [
+ "cache-key",
  "fs-err",
  "indoc",
  "once_cell",
@@ -2624,6 +2635,7 @@ version = "0.0.1"
 dependencies = [
  "anyhow",
  "bitflags 2.4.1",
+ "cache-key",
  "chrono",
  "clap",
  "colored",
diff --git a/crates/README.md b/crates/README.md
index 221877eb0..70badea53 100644
--- a/crates/README.md
+++ b/crates/README.md
@@ -4,6 +4,10 @@
 
 Functionality for benchmarking Puffin.
 
+## [cache-key](./cache-key)
+
+Generic functionality for caching paths, URLs, and other resources across platforms.
+
 ## [distribution-filename](./distribution-filename)
 
 Parse built distribution (wheel) and source distribution (sdist) filenames to extract structured
diff --git a/crates/cache-key/Cargo.toml b/crates/cache-key/Cargo.toml
new file mode 100644
index 000000000..2461eb3f1
--- /dev/null
+++ b/crates/cache-key/Cargo.toml
@@ -0,0 +1,19 @@
+[package]
+name = "cache-key"
+version = "0.0.1"
+description = "Generic functionality for caching paths, URLs, and other resources across platforms."
+edition = { workspace = true }
+rust-version = { workspace = true }
+homepage = { workspace = true }
+documentation = { workspace = true }
+repository = { workspace = true }
+authors = { workspace = true }
+license = { workspace = true }
+
+[lints]
+workspace = true
+
+[dependencies]
+hex = { workspace = true }
+seahash = { workspace = true }
+url = { workspace = true }
diff --git a/crates/puffin-cache/src/cache_key.rs b/crates/cache-key/src/cache_key.rs
similarity index 100%
rename from crates/puffin-cache/src/cache_key.rs
rename to crates/cache-key/src/cache_key.rs
diff --git a/crates/puffin-cache/src/canonical_url.rs b/crates/cache-key/src/canonical_url.rs
similarity index 100%
rename from crates/puffin-cache/src/canonical_url.rs
rename to crates/cache-key/src/canonical_url.rs
diff --git a/crates/puffin-cache/src/digest.rs b/crates/cache-key/src/digest.rs
similarity index 100%
rename from crates/puffin-cache/src/digest.rs
rename to crates/cache-key/src/digest.rs
diff --git a/crates/cache-key/src/lib.rs b/crates/cache-key/src/lib.rs
new file mode 100644
index 000000000..60b774462
--- /dev/null
+++ b/crates/cache-key/src/lib.rs
@@ -0,0 +1,8 @@
+pub use canonical_url::{CanonicalUrl, RepositoryUrl};
+pub use digest::digest;
+pub use stable_hash::{StableHash, StableHasher};
+
+mod cache_key;
+mod canonical_url;
+mod digest;
+mod stable_hash;
diff --git a/crates/puffin-cache/src/stable_hash.rs b/crates/cache-key/src/stable_hash.rs
similarity index 100%
rename from crates/puffin-cache/src/stable_hash.rs
rename to crates/cache-key/src/stable_hash.rs
diff --git a/crates/distribution-types/Cargo.toml b/crates/distribution-types/Cargo.toml
index 62fcaa6c6..0f1f8f953 100644
--- a/crates/distribution-types/Cargo.toml
+++ b/crates/distribution-types/Cargo.toml
@@ -13,10 +13,10 @@ license = { workspace = true }
 workspace = true
 
 [dependencies]
+cache-key = { path = "../cache-key" }
 distribution-filename = { path = "../distribution-filename" }
 pep440_rs = { path = "../pep440-rs" }
 pep508_rs = { path = "../pep508-rs" }
-puffin-cache = { path = "../puffin-cache" }
 puffin-git = { path = "../puffin-git" }
 puffin-normalize = { path = "../puffin-normalize" }
 pypi-types = { path = "../pypi-types" }
diff --git a/crates/distribution-types/src/lib.rs b/crates/distribution-types/src/lib.rs
index f25354f74..47efe5cc7 100644
--- a/crates/distribution-types/src/lib.rs
+++ b/crates/distribution-types/src/lib.rs
@@ -639,13 +639,11 @@ impl RemoteSource for Dist {
 
 impl Identifier for Url {
     fn distribution_id(&self) -> DistributionId {
-        DistributionId::new(puffin_cache::digest(&puffin_cache::CanonicalUrl::new(self)))
+        DistributionId::new(cache_key::digest(&cache_key::CanonicalUrl::new(self)))
     }
 
     fn resource_id(&self) -> ResourceId {
-        ResourceId::new(puffin_cache::digest(&puffin_cache::RepositoryUrl::new(
-            self,
-        )))
+        ResourceId::new(cache_key::digest(&cache_key::RepositoryUrl::new(self)))
     }
 }
 
@@ -661,11 +659,11 @@ impl Identifier for File {
 
 impl Identifier for Path {
     fn distribution_id(&self) -> DistributionId {
-        DistributionId::new(puffin_cache::digest(&self))
+        DistributionId::new(cache_key::digest(&self))
     }
 
     fn resource_id(&self) -> ResourceId {
-        ResourceId::new(puffin_cache::digest(&self))
+        ResourceId::new(cache_key::digest(&self))
     }
 }
 
diff --git a/crates/distribution-types/src/traits.rs b/crates/distribution-types/src/traits.rs
index 3cd6ea3b5..705b15e8c 100644
--- a/crates/distribution-types/src/traits.rs
+++ b/crates/distribution-types/src/traits.rs
@@ -3,7 +3,6 @@ use std::borrow::Cow;
 use anyhow::Result;
 
 use pep508_rs::VerbatimUrl;
-use puffin_cache::CanonicalUrl;
 use puffin_normalize::PackageName;
 
 use crate::error::Error;
@@ -38,7 +37,7 @@ pub trait DistributionMetadata: Name {
                 // `version` is normalized by its `ToString` impl
                 format!("{}-{}", self.name().as_dist_info_name(), version)
             }
-            VersionOrUrl::Url(url) => puffin_cache::digest(&CanonicalUrl::new(url)),
+            VersionOrUrl::Url(url) => cache_key::digest(&cache_key::CanonicalUrl::new(url)),
         })
     }
 }
diff --git a/crates/puffin-cache/Cargo.toml b/crates/puffin-cache/Cargo.toml
index a85339bae..0e66eabc0 100644
--- a/crates/puffin-cache/Cargo.toml
+++ b/crates/puffin-cache/Cargo.toml
@@ -14,6 +14,7 @@ license = { workspace = true }
 workspace = true
 
 [dependencies]
+cache-key = { path = "../cache-key" }
 puffin-fs = { path = "../puffin-fs" }
 puffin-normalize = { path = "../puffin-normalize" }
 pypi-types = { path = "../pypi-types" }
@@ -22,8 +23,6 @@ cachedir = { workspace = true }
 clap = { workspace = true, features = ["derive"], optional = true }
 directories = { workspace = true }
 fs-err = { workspace = true, features = ["tokio"] }
-hex = { workspace = true }
-seahash = { workspace = true }
 serde = { workspace = true, features = ["derive"] }
 tempfile = { workspace = true }
 tracing = { workspace = true }
diff --git a/crates/puffin-cache/src/lib.rs b/crates/puffin-cache/src/lib.rs
index 8171c0cca..3fa3a94a6 100644
--- a/crates/puffin-cache/src/lib.rs
+++ b/crates/puffin-cache/src/lib.rs
@@ -9,23 +9,17 @@ use fs_err as fs;
 use tempfile::{tempdir, TempDir};
 use tracing::debug;
 
-use crate::wheel::WheelCacheKind;
-pub use by_timestamp::CachedByTimestamp;
-pub use canonical_url::{CanonicalUrl, RepositoryUrl};
-#[cfg(feature = "clap")]
-pub use cli::CacheArgs;
-pub use digest::digest;
 use puffin_fs::{directories, force_remove_all};
 use puffin_normalize::PackageName;
-pub use stable_hash::{StableHash, StableHasher};
-pub use wheel::WheelCache;
+
+pub use crate::by_timestamp::CachedByTimestamp;
+#[cfg(feature = "clap")]
+pub use crate::cli::CacheArgs;
+pub use crate::wheel::WheelCache;
+use crate::wheel::WheelCacheKind;
 
 mod by_timestamp;
-mod cache_key;
-mod canonical_url;
 mod cli;
-mod digest;
-mod stable_hash;
 mod wheel;
 
 /// A cache entry which may or may not exist yet.
diff --git a/crates/puffin-cache/src/wheel.rs b/crates/puffin-cache/src/wheel.rs
index e560ce4b9..3acb34d60 100644
--- a/crates/puffin-cache/src/wheel.rs
+++ b/crates/puffin-cache/src/wheel.rs
@@ -2,11 +2,11 @@ use std::path::{Path, PathBuf};
 
 use url::Url;
 
+use cache_key::{digest, CanonicalUrl};
 use pypi_types::IndexUrl;
 
 #[allow(unused_imports)] // For rustdoc
 use crate::CacheBucket;
-use crate::{digest, CanonicalUrl};
 
 /// Cache wheels and their metadata, both from remote wheels and built from source distributions.
 ///
diff --git a/crates/puffin-client/Cargo.toml b/crates/puffin-client/Cargo.toml
index 53e36b34c..4c84a26d4 100644
--- a/crates/puffin-client/Cargo.toml
+++ b/crates/puffin-client/Cargo.toml
@@ -4,6 +4,7 @@ version = "0.0.1"
 edition = "2021"
 
 [dependencies]
+cache-key = { path = "../cache-key" }
 distribution-filename = { path = "../distribution-filename", features = ["serde"] }
 distribution-types = { path = "../distribution-types" }
 install-wheel-rs = { path = "../install-wheel-rs" }
diff --git a/crates/puffin-client/src/registry_client.rs b/crates/puffin-client/src/registry_client.rs
index d8c88dee6..2d17f5527 100644
--- a/crates/puffin-client/src/registry_client.rs
+++ b/crates/puffin-client/src/registry_client.rs
@@ -20,7 +20,7 @@ use distribution_filename::{DistFilename, SourceDistFilename, WheelFilename};
 use distribution_types::{BuiltDist, Name};
 use install_wheel_rs::find_dist_info;
 use pep440_rs::Version;
-use puffin_cache::{digest, Cache, CacheBucket, CanonicalUrl, WheelCache};
+use puffin_cache::{Cache, CacheBucket, WheelCache};
 use puffin_normalize::PackageName;
 use pypi_types::{File, IndexUrl, IndexUrls, Metadata21, SimpleJson};
 
@@ -143,7 +143,7 @@ impl RegistryClient {
                 CacheBucket::Simple,
                 Path::new(&match index {
                     IndexUrl::Pypi => "pypi".to_string(),
-                    IndexUrl::Url(url) => digest(&CanonicalUrl::new(url)),
+                    IndexUrl::Url(url) => cache_key::digest(&cache_key::CanonicalUrl::new(url)),
                 }),
                 format!("{}.msgpack", package_name.as_ref()),
             );
diff --git a/crates/puffin-distribution/Cargo.toml b/crates/puffin-distribution/Cargo.toml
index 9f9a2e8b6..7012bfeda 100644
--- a/crates/puffin-distribution/Cargo.toml
+++ b/crates/puffin-distribution/Cargo.toml
@@ -13,6 +13,7 @@ license = { workspace = true }
 workspace = true
 
 [dependencies]
+cache-key = { path = "../cache-key" }
 distribution-filename = { path = "../distribution-filename", features = ["serde"] }
 distribution-types = { path = "../distribution-types" }
 install-wheel-rs = { path = "../install-wheel-rs" }
diff --git a/crates/puffin-distribution/src/distribution_database.rs b/crates/puffin-distribution/src/distribution_database.rs
index ee9bd2c62..9fd3c0105 100644
--- a/crates/puffin-distribution/src/distribution_database.rs
+++ b/crates/puffin-distribution/src/distribution_database.rs
@@ -15,7 +15,7 @@ use url::Url;
 use distribution_filename::{WheelFilename, WheelFilenameError};
 use distribution_types::{BuiltDist, DirectGitUrl, Dist, LocalEditable, Name, SourceDist};
 use platform_tags::Tags;
-use puffin_cache::{digest, Cache, CacheBucket, WheelCache};
+use puffin_cache::{Cache, CacheBucket, WheelCache};
 use puffin_client::RegistryClient;
 use puffin_git::GitSource;
 use puffin_traits::BuildContext;
@@ -288,7 +288,7 @@ impl<'a, Context: BuildContext + Send + Sync> DistributionDatabase<'a, Context>
             dist,
             filename,
             path: editable_wheel_dir.join(disk_filename),
-            target: editable_wheel_dir.join(digest(&editable.path)),
+            target: editable_wheel_dir.join(cache_key::digest(&editable.path)),
         };
         Ok((LocalWheel::Built(built_wheel), metadata))
     }
diff --git a/crates/puffin-distribution/src/source_dist.rs b/crates/puffin-distribution/src/source_dist.rs
index 55d65b9b8..0705d97c2 100644
--- a/crates/puffin-distribution/src/source_dist.rs
+++ b/crates/puffin-distribution/src/source_dist.rs
@@ -26,9 +26,7 @@ use distribution_types::{
 };
 use install_wheel_rs::read_dist_info;
 use platform_tags::Tags;
-use puffin_cache::{
-    digest, CacheBucket, CacheEntry, CacheShard, CachedByTimestamp, CanonicalUrl, WheelCache,
-};
+use puffin_cache::{CacheBucket, CacheEntry, CacheShard, CachedByTimestamp, WheelCache};
 use puffin_client::{CachedClient, CachedClientError, DataWithCachePolicy};
 use puffin_fs::{write_atomic, LockedFile};
 use puffin_git::{Fetch, GitSource};
@@ -653,8 +651,11 @@ impl<'a, T: BuildContext> SourceDistCachedBuilder<'a, T> {
         // Avoid races between different processes, too.
         let lock_dir = git_dir.join("locks");
         fs::create_dir_all(&lock_dir).await?;
-        let canonical_url = CanonicalUrl::new(url);
-        let _lock = LockedFile::acquire(lock_dir.join(digest(&canonical_url)), &canonical_url)?;
+        let canonical_url = cache_key::CanonicalUrl::new(url);
+        let _lock = LockedFile::acquire(
+            lock_dir.join(cache_key::digest(&canonical_url)),
+            &canonical_url,
+        )?;
 
         let DirectGitUrl { url, subdirectory } =
             DirectGitUrl::try_from(url).map_err(SourceDistError::Git)?;
diff --git a/crates/puffin-git/Cargo.toml b/crates/puffin-git/Cargo.toml
index 75a175b3b..14d823832 100644
--- a/crates/puffin-git/Cargo.toml
+++ b/crates/puffin-git/Cargo.toml
@@ -13,7 +13,7 @@ license = { workspace = true }
 workspace = true
 
 [dependencies]
-puffin-cache = { path = "../puffin-cache" }
+cache-key = { path = "../cache-key" }
 
 anyhow = { workspace = true }
 cargo-util = { workspace = true }
diff --git a/crates/puffin-git/src/source.rs b/crates/puffin-git/src/source.rs
index 5a1c5150d..d2c4c143a 100644
--- a/crates/puffin-git/src/source.rs
+++ b/crates/puffin-git/src/source.rs
@@ -8,7 +8,7 @@ use reqwest::Client;
 use tracing::debug;
 use url::Url;
 
-use puffin_cache::{digest, RepositoryUrl};
+use cache_key::{digest, RepositoryUrl};
 
 use crate::git::GitRemote;
 use crate::{FetchStrategy, GitSha, GitUrl};
diff --git a/crates/puffin-interpreter/Cargo.toml b/crates/puffin-interpreter/Cargo.toml
index cc6d186c2..8317658bd 100644
--- a/crates/puffin-interpreter/Cargo.toml
+++ b/crates/puffin-interpreter/Cargo.toml
@@ -13,6 +13,7 @@ license = { workspace = true }
 workspace = true
 
 [dependencies]
+cache-key = { path = "../cache-key" }
 pep440_rs = { path = "../pep440-rs" }
 pep508_rs = { path = "../pep508-rs", features = ["serde"] }
 platform-host = { path = "../platform-host" }
diff --git a/crates/puffin-interpreter/src/interpreter.rs b/crates/puffin-interpreter/src/interpreter.rs
index fe719f839..660b6161e 100644
--- a/crates/puffin-interpreter/src/interpreter.rs
+++ b/crates/puffin-interpreter/src/interpreter.rs
@@ -6,12 +6,12 @@ use once_cell::sync::OnceCell;
 use serde::{Deserialize, Serialize};
 use tracing::{debug, warn};
 
+use cache_key::digest;
 use pep440_rs::Version;
 use pep508_rs::MarkerEnvironment;
 use platform_host::{Platform, PlatformError};
 use platform_tags::Tags;
-use puffin_cache::CachedByTimestamp;
-use puffin_cache::{digest, Cache, CacheBucket};
+use puffin_cache::{Cache, CacheBucket, CachedByTimestamp};
 use puffin_fs::write_atomic_sync;
 
 use crate::python_platform::PythonPlatform;
diff --git a/crates/puffin-resolver/Cargo.toml b/crates/puffin-resolver/Cargo.toml
index 43b0c36c9..a3aa72ea6 100644
--- a/crates/puffin-resolver/Cargo.toml
+++ b/crates/puffin-resolver/Cargo.toml
@@ -13,6 +13,7 @@ license = { workspace = true }
 workspace = true
 
 [dependencies]
+cache-key = { path = "../cache-key" }
 distribution-filename = { path = "../distribution-filename", features = ["serde"] }
 distribution-types = { path = "../distribution-types" }
 install-wheel-rs = { path = "../install-wheel-rs" }
diff --git a/crates/puffin-resolver/src/pubgrub/dependencies.rs b/crates/puffin-resolver/src/pubgrub/dependencies.rs
index 201142046..4eac6caf6 100644
--- a/crates/puffin-resolver/src/pubgrub/dependencies.rs
+++ b/crates/puffin-resolver/src/pubgrub/dependencies.rs
@@ -4,7 +4,6 @@ use pubgrub::type_aliases::DependencyConstraints;
 use tracing::warn;
 
 use pep508_rs::{MarkerEnvironment, Requirement, VersionOrUrl};
-use puffin_cache::CanonicalUrl;
 use puffin_normalize::{ExtraName, PackageName};
 
 use crate::overrides::Overrides;
@@ -235,7 +234,7 @@ fn merge_package(
             PubGrubPackage::Package(name, _extra, Some(left)),
             PubGrubPackage::Package(.., Some(right)),
         ) => {
-            if CanonicalUrl::new(left) == CanonicalUrl::new(right) {
+            if cache_key::CanonicalUrl::new(left) == cache_key::CanonicalUrl::new(right) {
                 Ok(None)
             } else {
                 Err(ResolveError::ConflictingUrls(
diff --git a/crates/puffin-resolver/src/resolver.rs b/crates/puffin-resolver/src/resolver.rs
index 257b2bb64..6face7e78 100644
--- a/crates/puffin-resolver/src/resolver.rs
+++ b/crates/puffin-resolver/src/resolver.rs
@@ -23,7 +23,6 @@ use distribution_types::{
 };
 use pep508_rs::{MarkerEnvironment, Requirement};
 use platform_tags::Tags;
-use puffin_cache::CanonicalUrl;
 use puffin_client::RegistryClient;
 use puffin_distribution::{DistributionDatabase, DistributionDatabaseError};
 use puffin_normalize::PackageName;
@@ -868,17 +867,17 @@ pub(crate) struct Index {
 }
 
 #[derive(Debug, Default)]
-struct AllowedUrls(FxHashSet<CanonicalUrl>);
+struct AllowedUrls(FxHashSet<cache_key::CanonicalUrl>);
 
 impl AllowedUrls {
     fn contains(&self, url: &Url) -> bool {
-        self.0.contains(&CanonicalUrl::new(url))
+        self.0.contains(&cache_key::CanonicalUrl::new(url))
     }
 }
 
 impl<'a> FromIterator<&'a Url> for AllowedUrls {
     fn from_iter<T: IntoIterator<Item = &'a Url>>(iter: T) -> Self {
-        Self(iter.into_iter().map(CanonicalUrl::new).collect())
+        Self(iter.into_iter().map(cache_key::CanonicalUrl::new).collect())
     }
 }