diff --git a/crates/ely_browser_core/src/state.rs b/crates/ely_browser_core/src/state.rs
index a744695..6abd085 100644
--- a/crates/ely_browser_core/src/state.rs
+++ b/crates/ely_browser_core/src/state.rs
@@ -304,186 +304,3 @@ fn search_url(query: &str) -> Result<UrlText, CoreError> {
     url.query_pairs_mut().append_pair("q", query);
     UrlText::parse(url.to_string()).map_err(CoreError::from)
 }
-
-#[cfg(test)]
-mod tests {
-    use std::error::Error;
-
-    use ely_domain::{CommandIntent, CommandScope, UrlText};
-
-    use super::{BrowserCore, InitialBrowserConfig};
-    use crate::CoreError;
-
-    #[test]
-    fn opens_new_tab_below_active_tab() -> Result<(), Box<dyn Error>> {
-        let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
-        let first_tab_id = core.active_tab()?.id().clone();
-        let second_tab_id = core.open_tab(UrlText::parse("https://example.com")?);
-
-        core.select_tab(&first_tab_id)?;
-        let third_tab_id = core.open_tab(UrlText::parse("https://servo.org")?);
-
-        let snapshot = core.snapshot()?;
-        let ordered_ids = snapshot.tabs.iter().map(|tab| tab.id().clone()).collect::<Vec<_>>();
-
-        assert_eq!(ordered_ids, vec![first_tab_id, third_tab_id.clone(), second_tab_id]);
-        assert_eq!(snapshot.active_tab_id, third_tab_id);
-        Ok(())
-    }
-
-    #[test]
-    fn closes_active_tab_and_selects_next_neighbor() -> Result<(), Box<dyn Error>> {
-        let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
-        let first_tab_id = core.active_tab()?.id().clone();
-        let second_tab_id = core.open_tab(UrlText::parse("https://example.com")?);
-        let third_tab_id = core.open_tab(UrlText::parse("https://servo.org")?);
-
-        core.select_tab(&second_tab_id)?;
-        let active_tab_id = core.close_active_tab()?;
-
-        let snapshot = core.snapshot()?;
-        let ordered_ids = snapshot.tabs.iter().map(|tab| tab.id().clone()).collect::<Vec<_>>();
-
-        assert_eq!(active_tab_id, third_tab_id);
-        assert_eq!(ordered_ids, vec![first_tab_id, active_tab_id.clone()]);
-        assert_eq!(snapshot.active_tab_id, active_tab_id);
-        Ok(())
-    }
-
-    #[test]
-    fn closing_last_tab_replaces_it_with_new_tab() -> Result<(), Box<dyn Error>> {
-        let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
-        let closed_tab_id = core.active_tab()?.id().clone();
-
-        let active_tab_id = core.close_tab(&closed_tab_id)?;
-
-        let snapshot = core.snapshot()?;
-        assert_eq!(snapshot.tabs.len(), 1);
-        assert_eq!(snapshot.active_tab_id, active_tab_id);
-        let replacement_tab = snapshot.tabs.first().ok_or(CoreError::MissingActiveTab)?;
-        assert_eq!(replacement_tab.url().as_str(), "ely://new-tab");
-        Ok(())
-    }
-
-    #[test]
-    fn selects_next_tab_with_wraparound() -> Result<(), Box<dyn Error>> {
-        let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
-        let first_tab_id = core.active_tab()?.id().clone();
-        let second_tab_id = core.open_tab(UrlText::parse("https://example.com")?);
-        let third_tab_id = core.open_tab(UrlText::parse("https://servo.org")?);
-
-        core.select_tab(&first_tab_id)?;
-        let next_tab_id = core.select_next_tab()?;
-        assert_eq!(next_tab_id, second_tab_id);
-
-        core.select_tab(&third_tab_id)?;
-        let wrapped_tab_id = core.select_next_tab()?;
-        assert_eq!(wrapped_tab_id, first_tab_id);
-        Ok(())
-    }
-
-    #[test]
-    fn selects_previous_tab_with_wraparound() -> Result<(), Box<dyn Error>> {
-        let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
-        let first_tab_id = core.active_tab()?.id().clone();
-        let second_tab_id = core.open_tab(UrlText::parse("https://example.com")?);
-        let third_tab_id = core.open_tab(UrlText::parse("https://servo.org")?);
-
-        let previous_tab_id = core.select_previous_tab()?;
-        assert_eq!(previous_tab_id, second_tab_id);
-
-        core.select_tab(&first_tab_id)?;
-        let wrapped_tab_id = core.select_previous_tab()?;
-        assert_eq!(wrapped_tab_id, third_tab_id);
-        Ok(())
-    }
-
-    #[test]
-    fn tab_scoped_search_selects_matching_open_tab() -> Result<(), Box<dyn Error>> {
-        let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
-        let first_tab_id = core.active_tab()?.id().clone();
-        core.open_tab(UrlText::parse("https://example.com")?);
-        let servo_tab_id = core.open_tab(UrlText::parse("https://servo.org")?);
-
-        core.select_tab(&first_tab_id)?;
-        core.set_command_query("@tabs servo");
-        let intent = core.submit_command()?;
-
-        let snapshot = core.snapshot()?;
-        assert!(matches!(
-            intent,
-            Some(CommandIntent::ScopedSearch { scope: CommandScope::Tabs, query }) if query == "servo"
-        ));
-        assert_eq!(snapshot.active_tab_id, servo_tab_id);
-        assert_eq!(snapshot.command_query, "");
-        Ok(())
-    }
-
-    #[test]
-    fn tab_scoped_search_preserves_query_without_match() -> Result<(), Box<dyn Error>> {
-        let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
-        let active_tab_id = core.active_tab()?.id().clone();
-
-        core.set_command_query("@tabs absent");
-        core.submit_command()?;
-
-        let snapshot = core.snapshot()?;
-        assert_eq!(snapshot.active_tab_id, active_tab_id);
-        assert_eq!(snapshot.command_query, "@tabs absent");
-        Ok(())
-    }
-
-    #[test]
-    fn search_command_opens_default_search_url() -> Result<(), Box<dyn Error>> {
-        let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
-
-        core.set_command_query("? rust async book");
-        let intent = core.submit_command()?;
-
-        let active_tab = core.active_tab()?;
-        assert_eq!(intent, Some(CommandIntent::Search("rust async book".to_string())));
-        assert_eq!(active_tab.url().as_str(), "https://duckduckgo.com/?q=rust+async+book");
-        assert_eq!(core.command_query(), "");
-        Ok(())
-    }
-
-    #[test]
-    fn toggles_active_tab_favorite() -> Result<(), Box<dyn Error>> {
-        let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
-
-        let favorite = core.toggle_active_tab_favorite()?;
-        let snapshot = core.snapshot()?;
-
-        assert!(favorite);
-        assert_eq!(snapshot.favorites.len(), 1);
-        assert_eq!(snapshot.favorites[0].id(), &snapshot.active_tab_id);
-
-        let favorite = core.toggle_active_tab_favorite()?;
-        let snapshot = core.snapshot()?;
-
-        assert!(!favorite);
-        assert!(snapshot.favorites.is_empty());
-        Ok(())
-    }
-
-    #[test]
-    fn enforces_default_favorite_limit() -> Result<(), Box<dyn Error>> {
-        let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
-
-        core.toggle_active_tab_favorite()?;
-        for index in 1..12 {
-            core.open_tab(UrlText::parse(format!("https://example.com/{index}"))?);
-            core.toggle_active_tab_favorite()?;
-        }
-
-        core.open_tab(UrlText::parse("https://example.com/overflow")?);
-        let error = match core.toggle_active_tab_favorite() {
-            Err(error) => error,
-            Ok(_) => return Err("favorite limit should apply".into()),
-        };
-
-        assert_eq!(error, CoreError::FavoriteLimitReached { limit: 12 });
-        assert_eq!(core.snapshot()?.favorites.len(), 12);
-        Ok(())
-    }
-}
diff --git a/crates/ely_browser_core/tests/tabs.rs b/crates/ely_browser_core/tests/tabs.rs
new file mode 100644
index 0000000..1e33a59
--- /dev/null
+++ b/crates/ely_browser_core/tests/tabs.rs
@@ -0,0 +1,177 @@
+use std::error::Error;
+
+use ely_browser_core::{BrowserCore, CoreError, InitialBrowserConfig};
+use ely_domain::{CommandIntent, CommandScope, UrlText};
+
+#[test]
+fn opens_new_tab_below_active_tab() -> Result<(), Box<dyn Error>> {
+    let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
+    let first_tab_id = core.active_tab()?.id().clone();
+    let second_tab_id = core.open_tab(UrlText::parse("https://example.com")?);
+
+    core.select_tab(&first_tab_id)?;
+    let third_tab_id = core.open_tab(UrlText::parse("https://servo.org")?);
+
+    let snapshot = core.snapshot()?;
+    let ordered_ids = snapshot.tabs.iter().map(|tab| tab.id().clone()).collect::<Vec<_>>();
+
+    assert_eq!(ordered_ids, vec![first_tab_id, third_tab_id.clone(), second_tab_id]);
+    assert_eq!(snapshot.active_tab_id, third_tab_id);
+    Ok(())
+}
+
+#[test]
+fn closes_active_tab_and_selects_next_neighbor() -> Result<(), Box<dyn Error>> {
+    let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
+    let first_tab_id = core.active_tab()?.id().clone();
+    let second_tab_id = core.open_tab(UrlText::parse("https://example.com")?);
+    let third_tab_id = core.open_tab(UrlText::parse("https://servo.org")?);
+
+    core.select_tab(&second_tab_id)?;
+    let active_tab_id = core.close_active_tab()?;
+
+    let snapshot = core.snapshot()?;
+    let ordered_ids = snapshot.tabs.iter().map(|tab| tab.id().clone()).collect::<Vec<_>>();
+
+    assert_eq!(active_tab_id, third_tab_id);
+    assert_eq!(ordered_ids, vec![first_tab_id, active_tab_id.clone()]);
+    assert_eq!(snapshot.active_tab_id, active_tab_id);
+    Ok(())
+}
+
+#[test]
+fn closing_last_tab_replaces_it_with_new_tab() -> Result<(), Box<dyn Error>> {
+    let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
+    let closed_tab_id = core.active_tab()?.id().clone();
+
+    let active_tab_id = core.close_tab(&closed_tab_id)?;
+
+    let snapshot = core.snapshot()?;
+    assert_eq!(snapshot.tabs.len(), 1);
+    assert_eq!(snapshot.active_tab_id, active_tab_id);
+    let replacement_tab = snapshot.tabs.first().ok_or(CoreError::MissingActiveTab)?;
+    assert_eq!(replacement_tab.url().as_str(), "ely://new-tab");
+    Ok(())
+}
+
+#[test]
+fn selects_next_tab_with_wraparound() -> Result<(), Box<dyn Error>> {
+    let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
+    let first_tab_id = core.active_tab()?.id().clone();
+    let second_tab_id = core.open_tab(UrlText::parse("https://example.com")?);
+    let third_tab_id = core.open_tab(UrlText::parse("https://servo.org")?);
+
+    core.select_tab(&first_tab_id)?;
+    let next_tab_id = core.select_next_tab()?;
+    assert_eq!(next_tab_id, second_tab_id);
+
+    core.select_tab(&third_tab_id)?;
+    let wrapped_tab_id = core.select_next_tab()?;
+    assert_eq!(wrapped_tab_id, first_tab_id);
+    Ok(())
+}
+
+#[test]
+fn selects_previous_tab_with_wraparound() -> Result<(), Box<dyn Error>> {
+    let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
+    let first_tab_id = core.active_tab()?.id().clone();
+    let second_tab_id = core.open_tab(UrlText::parse("https://example.com")?);
+    let third_tab_id = core.open_tab(UrlText::parse("https://servo.org")?);
+
+    let previous_tab_id = core.select_previous_tab()?;
+    assert_eq!(previous_tab_id, second_tab_id);
+
+    core.select_tab(&first_tab_id)?;
+    let wrapped_tab_id = core.select_previous_tab()?;
+    assert_eq!(wrapped_tab_id, third_tab_id);
+    Ok(())
+}
+
+#[test]
+fn tab_scoped_search_selects_matching_open_tab() -> Result<(), Box<dyn Error>> {
+    let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
+    let first_tab_id = core.active_tab()?.id().clone();
+    core.open_tab(UrlText::parse("https://example.com")?);
+    let servo_tab_id = core.open_tab(UrlText::parse("https://servo.org")?);
+
+    core.select_tab(&first_tab_id)?;
+    core.set_command_query("@tabs servo");
+    let intent = core.submit_command()?;
+
+    let snapshot = core.snapshot()?;
+    assert!(matches!(
+        intent,
+        Some(CommandIntent::ScopedSearch { scope: CommandScope::Tabs, query }) if query == "servo"
+    ));
+    assert_eq!(snapshot.active_tab_id, servo_tab_id);
+    assert_eq!(snapshot.command_query, "");
+    Ok(())
+}
+
+#[test]
+fn tab_scoped_search_preserves_query_without_match() -> Result<(), Box<dyn Error>> {
+    let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
+    let active_tab_id = core.active_tab()?.id().clone();
+
+    core.set_command_query("@tabs absent");
+    core.submit_command()?;
+
+    let snapshot = core.snapshot()?;
+    assert_eq!(snapshot.active_tab_id, active_tab_id);
+    assert_eq!(snapshot.command_query, "@tabs absent");
+    Ok(())
+}
+
+#[test]
+fn search_command_opens_default_search_url() -> Result<(), Box<dyn Error>> {
+    let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
+
+    core.set_command_query("? rust async book");
+    let intent = core.submit_command()?;
+
+    let active_tab = core.active_tab()?;
+    assert_eq!(intent, Some(CommandIntent::Search("rust async book".to_string())));
+    assert_eq!(active_tab.url().as_str(), "https://duckduckgo.com/?q=rust+async+book");
+    assert_eq!(core.command_query(), "");
+    Ok(())
+}
+
+#[test]
+fn toggles_active_tab_favorite() -> Result<(), Box<dyn Error>> {
+    let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
+
+    let favorite = core.toggle_active_tab_favorite()?;
+    let snapshot = core.snapshot()?;
+
+    assert!(favorite);
+    assert_eq!(snapshot.favorites.len(), 1);
+    assert_eq!(snapshot.favorites[0].id(), &snapshot.active_tab_id);
+
+    let favorite = core.toggle_active_tab_favorite()?;
+    let snapshot = core.snapshot()?;
+
+    assert!(!favorite);
+    assert!(snapshot.favorites.is_empty());
+    Ok(())
+}
+
+#[test]
+fn enforces_default_favorite_limit() -> Result<(), Box<dyn Error>> {
+    let mut core = BrowserCore::new(InitialBrowserConfig::ely_defaults()?)?;
+
+    core.toggle_active_tab_favorite()?;
+    for index in 1..12 {
+        core.open_tab(UrlText::parse(format!("https://example.com/{index}"))?);
+        core.toggle_active_tab_favorite()?;
+    }
+
+    core.open_tab(UrlText::parse("https://example.com/overflow")?);
+    let error = match core.toggle_active_tab_favorite() {
+        Err(error) => error,
+        Ok(_) => return Err("favorite limit should apply".into()),
+    };
+
+    assert_eq!(error, CoreError::FavoriteLimitReached { limit: 12 });
+    assert_eq!(core.snapshot()?.favorites.len(), 12);
+    Ok(())
+}