diff --git a/kiln-core/src/map_file.rs b/kiln-core/src/map_file.rs
index 8cc06c0..cacb52f 100644
--- a/kiln-core/src/map_file.rs
+++ b/kiln-core/src/map_file.rs
@@ -583,9 +583,9 @@ impl From<&Board> for MapFile {
             for x in 0..board.width {
                 let (glyph, arch) = board.get(x, y);
                 let key = (*glyph, *arch);
-                if !cell_to_key.contains_key(&key) {
+                if let std::collections::hash_map::Entry::Vacant(e) = cell_to_key.entry(key) {
                     if key == canonical_empty {
-                        cell_to_key.insert(key, ' ');
+                        e.insert(' ');
                         palette.insert(
                             " ".to_string(),
                             PaletteEntry {
@@ -599,7 +599,7 @@ impl From<&Board> for MapFile {
                         let ch = *pool_iter
                             .next()
                             .expect("board has more than 92 unique non-canonical cell types");
-                        cell_to_key.insert(key, ch);
+                        e.insert(ch);
                         palette.insert(
                             ch.to_string(),
                             PaletteEntry {
diff --git a/kiln-core/src/script.rs b/kiln-core/src/script.rs
index 743a3f4..5ff7b96 100644
--- a/kiln-core/src/script.rs
+++ b/kiln-core/src/script.rs
@@ -430,7 +430,7 @@ fn register_read_api(engine: &mut Engine, board: &BoardRef, board_queue: &BoardQ
     let b = board.clone();
     engine.register_fn("has_tag", move |ctx: NativeCallContext, tag: ImmutableString| {
         let src = source_of(&ctx);
-        b.borrow().objects.get(&src).map_or(false, |o| o.tags.contains(tag.as_str()))
+        b.borrow().objects.get(&src).is_some_and(|o| o.tags.contains(tag.as_str()))
     });
 
     // get_tags() -> Array of strings: the calling object's current tag set.
diff --git a/kiln-core/src/tests/actions.rs b/kiln-core/src/tests/actions.rs
index 48201d7..539153f 100644
--- a/kiln-core/src/tests/actions.rs
+++ b/kiln-core/src/tests/actions.rs
@@ -2,7 +2,6 @@ use std::time::Duration;
 use crate::archetype::Archetype;
 use crate::board::tests::{crate_at, open_board, wall_at};
 use crate::game::GameState;
-use crate::script::Direction;
 use super::{scripted_object, log_texts};
 
 #[test]