diff --git a/src/error.rs b/src/error.rs
new file mode 100644
index 0000000..2e82d7e
--- /dev/null
+++ b/src/error.rs
@@ -0,0 +1,106 @@
+use std::{ffi::OsString, fmt, path::PathBuf};
+
+
+/// Type describing all errors that can occur in this library.
+pub struct Error {
+    pub(crate) inner: Box<ErrorInner>,
+}
+
+pub(crate) enum ErrorInner {
+    /// Returned by `Config::from_partial` when the partial does not contain
+    /// values for all required configuration values. The string is a
+    /// human-readable path to the value, e.g. `http.port`.
+    MissingValue(String),
+
+    /// An IO error occured, e.g. when reading a file.
+    Io {
+        path: Option<PathBuf>,
+        err: std::io::Error,
+    },
+
+    /// Returned by `Source::load` implementations when deserialization fails.
+    Deserialization {
+        /// A human readable description for the error message, describing from
+        /// what source it was attempted to deserialize. Completes the sentence
+        /// "failed to deserialize configuration from ". E.g. "file 'foo.toml'"
+        /// or "environment variable 'FOO_PORT'".
+        source: Option<String>,
+        err: Box<dyn std::error::Error + Send + Sync>,
+    },
+
+    /// Returned by the [`Source`] impls for `Path` and `PathBuf` if the file
+    /// extension is not supported by confique or if the corresponding Cargo
+    /// feature of confique was not enabled.
+    UnsupportedFileFormat {
+        path: PathBuf,
+        extension: OsString,
+    },
+
+    /// Returned by the [`Source`] impls for `Path` and `PathBuf` if the path
+    /// does not contain a file extension.
+    MissingFileExtension {
+        path: PathBuf,
+    }
+}
+
+impl std::error::Error for Error {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        match &*self.inner {
+            ErrorInner::Io { err, .. } => Some(err),
+            ErrorInner::Deserialization { err, .. } => Some(&**err),
+            ErrorInner::MissingValue(_)
+            | ErrorInner::UnsupportedFileFormat { .. }
+            | ErrorInner::MissingFileExtension { .. } => None,
+        }
+    }
+}
+
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match &*self.inner {
+            ErrorInner::MissingValue(path) => {
+                std::write!(f, "required configuration value is missing: '{}'", path)
+            }
+            ErrorInner::Io { path: Some(path), .. } => {
+                std::write!(f,
+                    "IO error occured while reading configuration file '{}'",
+                    path.display(),
+                )
+            }
+            ErrorInner::Io { path: None, .. } => {
+                std::write!(f, "IO error occured while loading configuration")
+            }
+            ErrorInner::Deserialization { source: Some(source), .. } => {
+                std::write!(f, "failed to deserialize configuration from {}", source)
+            }
+            ErrorInner::Deserialization { source: None, .. } => {
+                std::write!(f, "failed to deserialize configuration")
+            }
+            ErrorInner::UnsupportedFileFormat { path, extension } => {
+                std::write!(f,
+                    "unknown configuration file format '{}' of '{}'",
+                    extension.to_string_lossy(),
+                    path.display(),
+                )
+            }
+            ErrorInner::MissingFileExtension { path } => {
+                std::write!(f,
+                    "cannot guess configuration file format due to missing file extension in '{}'",
+                    path.display(),
+                )
+            }
+        }
+    }
+}
+
+impl fmt::Debug for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fmt::Display::fmt(self, f)
+    }
+}
+
+impl From<ErrorInner> for Error {
+    fn from(inner: ErrorInner) -> Self {
+        Self { inner: Box::new(inner) }
+    }
+}
diff --git a/src/file.rs b/src/file.rs
index 524c03b..93829c1 100644
--- a/src/file.rs
+++ b/src/file.rs
@@ -1,6 +1,6 @@
 use std::{ffi::OsStr, fs, io, path::{Path, PathBuf}};
 
-use crate::{Config, Error, ErrorInner, Partial, Source};
+use crate::{Config, Error, Partial, Source, error::ErrorInner};
 
 
 impl<C: Config> Source<C> for &Path {
diff --git a/src/internal.rs b/src/internal.rs
index 734810e..3ee4e75 100644
--- a/src/internal.rs
+++ b/src/internal.rs
@@ -2,7 +2,7 @@
 //! intended to be used directly. None of this is covered by semver! Do not use
 //! any of this directly.
 
-use crate::{Error, ErrorInner};
+use crate::{Error, error::ErrorInner};
 
 pub fn deserialize_default<I, O>(src: I) -> Result<O, serde::de::value::Error>
 where
diff --git a/src/lib.rs b/src/lib.rs
index fa39e34..83522fd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,16 +1,19 @@
-use std::{ffi::OsString, fmt, path::PathBuf};
-
 use serde::Deserialize;
 
 #[doc(hidden)]
 pub mod internal;
 
+mod error;
 mod file;
 
 
 pub use serde;
 pub use confique_macro::Config;
-pub use self::file::{File, FileFormat};
+pub use self::{
+    error::Error,
+    file::{File, FileFormat},
+};
+
 
 
 /// A configuration object that can be deserialized in layers via `serde`.
@@ -83,107 +86,3 @@ pub trait Source<C: Config> {
     /// Attempts to load a potentially partially configuration object.
     fn load(&self) -> Result<C::Partial, Error>;
 }
-
-/// Type describing all errors that can occur in this library.
-pub struct Error {
-    inner: Box<ErrorInner>,
-}
-
-enum ErrorInner {
-    /// Returned by `Config::from_partial` when the partial does not contain
-    /// values for all required configuration values. The string is a
-    /// human-readable path to the value, e.g. `http.port`.
-    MissingValue(String),
-
-    /// An IO error occured, e.g. when reading a file.
-    Io {
-        path: Option<PathBuf>,
-        err: std::io::Error,
-    },
-
-    /// Returned by `Source::load` implementations when deserialization fails.
-    Deserialization {
-        /// A human readable description for the error message, describing from
-        /// what source it was attempted to deserialize. Completes the sentence
-        /// "failed to deserialize configuration from ". E.g. "file 'foo.toml'"
-        /// or "environment variable 'FOO_PORT'".
-        source: Option<String>,
-        err: Box<dyn std::error::Error + Send + Sync>,
-    },
-
-    /// Returned by the [`Source`] impls for `Path` and `PathBuf` if the file
-    /// extension is not supported by confique or if the corresponding Cargo
-    /// feature of confique was not enabled.
-    UnsupportedFileFormat {
-        path: PathBuf,
-        extension: OsString,
-    },
-
-    /// Returned by the [`Source`] impls for `Path` and `PathBuf` if the path
-    /// does not contain a file extension.
-    MissingFileExtension {
-        path: PathBuf,
-    }
-}
-
-impl std::error::Error for Error {
-    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
-        match &*self.inner {
-            ErrorInner::Io { err, .. } => Some(err),
-            ErrorInner::Deserialization { err, .. } => Some(&**err),
-            ErrorInner::MissingValue(_)
-            | ErrorInner::UnsupportedFileFormat { .. }
-            | ErrorInner::MissingFileExtension { .. } => None,
-        }
-    }
-}
-
-impl fmt::Display for Error {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match &*self.inner {
-            ErrorInner::MissingValue(path) => {
-                std::write!(f, "required configuration value is missing: '{}'", path)
-            }
-            ErrorInner::Io { path: Some(path), .. } => {
-                std::write!(f,
-                    "IO error occured while reading configuration file '{}'",
-                    path.display(),
-                )
-            }
-            ErrorInner::Io { path: None, .. } => {
-                std::write!(f, "IO error occured while loading configuration")
-            }
-            ErrorInner::Deserialization { source: Some(source), .. } => {
-                std::write!(f, "failed to deserialize configuration from {}", source)
-            }
-            ErrorInner::Deserialization { source: None, .. } => {
-                std::write!(f, "failed to deserialize configuration")
-            }
-            ErrorInner::UnsupportedFileFormat { path, extension } => {
-                std::write!(f,
-                    "unknown configuration file format '{}' of '{}'",
-                    extension.to_string_lossy(),
-                    path.display(),
-                )
-            }
-            ErrorInner::MissingFileExtension { path } => {
-                std::write!(f,
-                    "cannot guess configuration file format due to missing file extension in '{}'",
-                    path.display(),
-                )
-            }
-        }
-    }
-}
-
-impl fmt::Debug for Error {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        fmt::Display::fmt(self, f)
-    }
-}
-
-impl From<ErrorInner> for Error {
-    fn from(inner: ErrorInner) -> Self {
-        Self { inner: Box::new(inner) }
-    }
-}