diff --git a/Cargo.toml b/Cargo.toml
index 32bfee8..099f65f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -31,12 +31,12 @@ default = ["database-json", "library-beets"]
 bin = ["structopt"]
 database-json = ["serde", "serde_json"]
 library-beets = []
-ssh-library = ["openssh", "tokio"]
+library-beets-ssh = ["openssh", "tokio"]
 tui = ["aho-corasick", "crossterm", "once_cell", "ratatui"]
 
 [[bin]]
 name = "musichoard"
-required-features = ["bin", "database-json", "library-beets", "ssh-library", "tui"]
+required-features = ["bin", "database-json", "library-beets", "library-beets-ssh", "tui"]
 
 [[bin]]
 name = "musichoard-edit"
diff --git a/src/core/database/mod.rs b/src/core/interface/database/mod.rs
similarity index 97%
rename from src/core/database/mod.rs
rename to src/core/interface/database/mod.rs
index b3882c1..9ae7435 100644
--- a/src/core/database/mod.rs
+++ b/src/core/interface/database/mod.rs
@@ -1,10 +1,5 @@
 //! Module for storing MusicHoard data in a database.
 
-#[cfg(feature = "database-json")]
-pub mod json;
-#[cfg(feature = "database-json")]
-mod serde;
-
 use std::fmt;
 
 #[cfg(test)]
diff --git a/src/core/library/mod.rs b/src/core/interface/library/mod.rs
similarity index 93%
rename from src/core/library/mod.rs
rename to src/core/interface/library/mod.rs
index 7797c07..448e063 100644
--- a/src/core/library/mod.rs
+++ b/src/core/interface/library/mod.rs
@@ -1,8 +1,5 @@
 //! Module for interacting with the music library.
 
-#[cfg(feature = "library-beets")]
-pub mod beets;
-
 use std::{collections::HashSet, fmt, num::ParseIntError, str::Utf8Error};
 
 #[cfg(test)]
@@ -59,26 +56,16 @@ pub enum Field {
 }
 
 /// A library query. Can include or exclude particular fields.
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Debug, Default, PartialEq, Eq)]
 pub struct Query {
-    include: HashSet<Field>,
-    exclude: HashSet<Field>,
-}
-
-impl Default for Query {
-    /// Create an empty query.
-    fn default() -> Self {
-        Self::new()
-    }
+    pub include: HashSet<Field>,
+    pub exclude: HashSet<Field>,
 }
 
 impl Query {
     /// Create an empty query.
     pub fn new() -> Self {
-        Query {
-            include: HashSet::new(),
-            exclude: HashSet::new(),
-        }
+        Query::default()
     }
 
     /// Refine the query to include a particular search term.
diff --git a/src/core/library/testmod.rs b/src/core/interface/library/testmod.rs
similarity index 99%
rename from src/core/library/testmod.rs
rename to src/core/interface/library/testmod.rs
index 09e56b8..2649422 100644
--- a/src/core/library/testmod.rs
+++ b/src/core/interface/library/testmod.rs
@@ -2,7 +2,7 @@ use once_cell::sync::Lazy;
 
 use crate::core::{
     collection::{album::AlbumMonth, track::TrackFormat},
-    library::Item,
+    interface::library::Item,
 };
 
 pub static LIBRARY_ITEMS: Lazy<Vec<Item>> = Lazy::new(|| -> Vec<Item> {
diff --git a/src/core/interface/mod.rs b/src/core/interface/mod.rs
new file mode 100644
index 0000000..2b9c4cf
--- /dev/null
+++ b/src/core/interface/mod.rs
@@ -0,0 +1,2 @@
+pub mod database;
+pub mod library;
diff --git a/src/core/mod.rs b/src/core/mod.rs
index 8739da3..8899a5d 100644
--- a/src/core/mod.rs
+++ b/src/core/mod.rs
@@ -1,6 +1,5 @@
 pub mod collection;
-pub mod database;
-pub mod library;
+pub mod interface;
 pub mod musichoard;
 
 #[cfg(test)]
diff --git a/src/core/musichoard/mod.rs b/src/core/musichoard/mod.rs
index d12bc43..41dc276 100644
--- a/src/core/musichoard/mod.rs
+++ b/src/core/musichoard/mod.rs
@@ -6,7 +6,10 @@ pub mod musichoard_builder;
 
 use std::fmt::{self, Display};
 
-use crate::core::{collection, database, library};
+use crate::core::{
+    collection,
+    interface::{database, library},
+};
 
 /// Error type for `musichoard`.
 #[derive(Debug, PartialEq, Eq)]
diff --git a/src/core/musichoard/musichoard.rs b/src/core/musichoard/musichoard.rs
index 86d2ba8..2eafef3 100644
--- a/src/core/musichoard/musichoard.rs
+++ b/src/core/musichoard/musichoard.rs
@@ -8,8 +8,10 @@ use crate::core::{
         track::{Track, TrackId, TrackNum, TrackQuality},
         Collection, MergeCollections,
     },
-    database::IDatabase,
-    library::{ILibrary, Item, Query},
+    interface::{
+        database::IDatabase,
+        library::{ILibrary, Item, Query},
+    },
     musichoard::Error,
 };
 
@@ -468,8 +470,10 @@ mod tests {
 
     use crate::core::{
         collection::{artist::ArtistId, musicbrainz::MusicBrainz},
-        database::{self, MockIDatabase},
-        library::{self, testmod::LIBRARY_ITEMS, MockILibrary},
+        interface::{
+            database::{self, MockIDatabase},
+            library::{self, testmod::LIBRARY_ITEMS, MockILibrary},
+        },
         testmod::{FULL_COLLECTION, LIBRARY_COLLECTION},
     };
 
diff --git a/src/core/musichoard/musichoard_builder.rs b/src/core/musichoard/musichoard_builder.rs
index af48922..5b1bc5f 100644
--- a/src/core/musichoard/musichoard_builder.rs
+++ b/src/core/musichoard/musichoard_builder.rs
@@ -1,7 +1,6 @@
 use crate::{
     core::{
-        database::IDatabase,
-        library::ILibrary,
+        interface::{database::IDatabase, library::ILibrary},
         musichoard::musichoard::{MusicHoard, NoDatabase, NoLibrary},
     },
     Error,
@@ -79,7 +78,7 @@ impl<LIB: ILibrary, DB: IDatabase> MusicHoardBuilder<LIB, DB> {
 
 #[cfg(test)]
 mod tests {
-    use crate::core::{database::NullDatabase, library::NullLibrary};
+    use crate::core::interface::{database::NullDatabase, library::NullLibrary};
 
     use super::*;
 
diff --git a/src/core/database/json/backend.rs b/src/database/json/backend.rs
similarity index 94%
rename from src/core/database/json/backend.rs
rename to src/database/json/backend.rs
index 8c99542..07a0a1c 100644
--- a/src/core/database/json/backend.rs
+++ b/src/database/json/backend.rs
@@ -3,7 +3,7 @@
 use std::fs;
 use std::path::PathBuf;
 
-use crate::core::database::json::IJsonDatabaseBackend;
+use crate::database::json::IJsonDatabaseBackend;
 
 /// JSON database backend that uses a local file for persistent storage.
 pub struct JsonDatabaseFileBackend {
diff --git a/src/core/database/json/mod.rs b/src/database/json/mod.rs
similarity index 98%
rename from src/core/database/json/mod.rs
rename to src/database/json/mod.rs
index 5eec609..80cc6c7 100644
--- a/src/core/database/json/mod.rs
+++ b/src/database/json/mod.rs
@@ -7,7 +7,7 @@ use mockall::automock;
 
 use crate::core::{
     collection::Collection,
-    database::{IDatabase, LoadError, SaveError},
+    interface::database::{IDatabase, LoadError, SaveError},
 };
 
 use super::serde::{deserialize::DeserializeDatabase, serialize::SerializeDatabase};
diff --git a/src/core/database/json/testmod.rs b/src/database/json/testmod.rs
similarity index 100%
rename from src/core/database/json/testmod.rs
rename to src/database/json/testmod.rs
diff --git a/src/database/mod.rs b/src/database/mod.rs
new file mode 100644
index 0000000..8bc349c
--- /dev/null
+++ b/src/database/mod.rs
@@ -0,0 +1,4 @@
+#[cfg(feature = "database-json")]
+pub mod json;
+#[cfg(feature = "database-json")]
+mod serde;
diff --git a/src/core/database/serde/deserialize.rs b/src/database/serde/deserialize.rs
similarity index 98%
rename from src/core/database/serde/deserialize.rs
rename to src/database/serde/deserialize.rs
index 718601e..55bfbe9 100644
--- a/src/core/database/serde/deserialize.rs
+++ b/src/database/serde/deserialize.rs
@@ -9,7 +9,7 @@ use crate::core::{
         musicbrainz::MusicBrainz,
         Collection,
     },
-    database::LoadError,
+    interface::database::LoadError,
 };
 
 #[derive(Debug, Deserialize)]
diff --git a/src/core/database/serde/mod.rs b/src/database/serde/mod.rs
similarity index 100%
rename from src/core/database/serde/mod.rs
rename to src/database/serde/mod.rs
diff --git a/src/core/database/serde/serialize.rs b/src/database/serde/serialize.rs
similarity index 100%
rename from src/core/database/serde/serialize.rs
rename to src/database/serde/serialize.rs
diff --git a/src/lib.rs b/src/lib.rs
index 6277808..af8688a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,10 +1,11 @@
 //! MusicHoard - a music collection manager.
 
 mod core;
+pub mod database;
+pub mod library;
 
 pub use core::collection;
-pub use core::database;
-pub use core::library;
+pub use core::interface;
 
 pub use core::musichoard::{
     musichoard::{MusicHoard, NoDatabase, NoLibrary},
diff --git a/src/core/library/beets/executor.rs b/src/library/beets/executor.rs
similarity index 97%
rename from src/core/library/beets/executor.rs
rename to src/library/beets/executor.rs
index 4a9632e..68e799e 100644
--- a/src/core/library/beets/executor.rs
+++ b/src/library/beets/executor.rs
@@ -8,7 +8,8 @@ use std::{
     str,
 };
 
-use crate::core::library::{beets::IBeetsLibraryExecutor, Error};
+use crate::core::interface::library::Error;
+use crate::library::beets::IBeetsLibraryExecutor;
 
 const BEET_DEFAULT: &str = "beet";
 
@@ -74,7 +75,7 @@ impl IBeetsLibraryExecutor for BeetsLibraryProcessExecutor {
 impl IBeetsLibraryExecutorPrivate for BeetsLibraryProcessExecutor {}
 
 // GRCOV_EXCL_START
-#[cfg(feature = "ssh-library")]
+#[cfg(feature = "library-beets-ssh")]
 pub mod ssh {
     //! Module for interacting with the music library via
     //! [beets](https://beets.readthedocs.io/en/stable/) over SSH.
diff --git a/src/core/library/beets/mod.rs b/src/library/beets/mod.rs
similarity index 98%
rename from src/core/library/beets/mod.rs
rename to src/library/beets/mod.rs
index d67d90d..90c5307 100644
--- a/src/core/library/beets/mod.rs
+++ b/src/library/beets/mod.rs
@@ -8,7 +8,7 @@ use mockall::automock;
 
 use crate::core::{
     collection::track::TrackFormat,
-    library::{Error, Field, ILibrary, Item, Query},
+    interface::library::{Error, Field, ILibrary, Item, Query},
 };
 
 macro_rules! list_format_separator {
@@ -201,7 +201,7 @@ mod testmod;
 mod tests {
     use mockall::predicate;
 
-    use crate::{collection::album::AlbumMonth, core::library::testmod::LIBRARY_ITEMS};
+    use crate::{collection::album::AlbumMonth, core::interface::library::testmod::LIBRARY_ITEMS};
 
     use super::*;
     use testmod::LIBRARY_BEETS;
diff --git a/src/core/library/beets/testmod.rs b/src/library/beets/testmod.rs
similarity index 100%
rename from src/core/library/beets/testmod.rs
rename to src/library/beets/testmod.rs
diff --git a/src/library/mod.rs b/src/library/mod.rs
new file mode 100644
index 0000000..d0ca87d
--- /dev/null
+++ b/src/library/mod.rs
@@ -0,0 +1,2 @@
+#[cfg(feature = "library-beets")]
+pub mod beets;
diff --git a/src/main.rs b/src/main.rs
index 5c3dfa5..87e3140 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -10,16 +10,14 @@ use ratatui::{backend::CrosstermBackend, Terminal};
 use structopt::StructOpt;
 
 use musichoard::{
-    database::{
-        json::{backend::JsonDatabaseFileBackend, JsonDatabase},
-        IDatabase, NullDatabase,
+    database::json::{backend::JsonDatabaseFileBackend, JsonDatabase},
+    interface::{
+        database::{IDatabase, NullDatabase},
+        library::{ILibrary, NullLibrary},
     },
-    library::{
-        beets::{
-            executor::{ssh::BeetsLibrarySshExecutor, BeetsLibraryProcessExecutor},
-            BeetsLibrary,
-        },
-        ILibrary, NullLibrary,
+    library::beets::{
+        executor::{ssh::BeetsLibrarySshExecutor, BeetsLibraryProcessExecutor},
+        BeetsLibrary,
     },
     MusicHoardBuilder, NoDatabase, NoLibrary,
 };
diff --git a/src/tui/lib.rs b/src/tui/lib.rs
index 990851c..d75ddc8 100644
--- a/src/tui/lib.rs
+++ b/src/tui/lib.rs
@@ -1,4 +1,7 @@
-use musichoard::{collection::Collection, database::IDatabase, library::ILibrary, MusicHoard};
+use musichoard::{
+    collection::Collection, interface::database::IDatabase, interface::library::ILibrary,
+    MusicHoard,
+};
 
 #[cfg(test)]
 use mockall::automock;
diff --git a/tests/database/json.rs b/tests/database/json.rs
index f2c6c52..a72657a 100644
--- a/tests/database/json.rs
+++ b/tests/database/json.rs
@@ -5,10 +5,8 @@ use tempfile::NamedTempFile;
 
 use musichoard::{
     collection::{album::AlbumDate, artist::Artist, Collection},
-    database::{
-        json::{backend::JsonDatabaseFileBackend, JsonDatabase},
-        IDatabase,
-    },
+    database::json::{backend::JsonDatabaseFileBackend, JsonDatabase},
+    interface::database::IDatabase,
 };
 
 use crate::testlib::COLLECTION;
diff --git a/tests/library/beets.rs b/tests/library/beets.rs
index 74dcd12..0a7a066 100644
--- a/tests/library/beets.rs
+++ b/tests/library/beets.rs
@@ -7,9 +7,9 @@ use std::{
 
 use once_cell::sync::Lazy;
 
-use musichoard::library::{
-    beets::{executor::BeetsLibraryProcessExecutor, BeetsLibrary},
-    Field, ILibrary, Item, Query,
+use musichoard::{
+    interface::library::{Field, ILibrary, Item, Query},
+    library::beets::{executor::BeetsLibraryProcessExecutor, BeetsLibrary},
 };
 
 use crate::library::testmod::LIBRARY_ITEMS;
diff --git a/tests/library/testmod.rs b/tests/library/testmod.rs
index cb85c50..aa6e671 100644
--- a/tests/library/testmod.rs
+++ b/tests/library/testmod.rs
@@ -2,7 +2,7 @@ use once_cell::sync::Lazy;
 
 use musichoard::{
     collection::{album::AlbumMonth, track::TrackFormat},
-    library::Item,
+    interface::library::Item,
 };
 
 pub static LIBRARY_ITEMS: Lazy<Vec<Item>> = Lazy::new(|| -> Vec<Item> {