diff --git a/package/origlang-compiler-entrypoint/src/lib.rs b/package/origlang-compiler-entrypoint/src/lib.rs
index 4d7a8c6..fb17f03 100644
--- a/package/origlang-compiler-entrypoint/src/lib.rs
+++ b/package/origlang-compiler-entrypoint/src/lib.rs
@@ -63,8 +63,8 @@ impl TheCompiler {
         self
     }
 
-    pub fn compile(&self, source: String) -> Result<Vec<IR1>, PartialCompilation> {
-        let x = Parser::create(&source);
+    pub fn compile(&self, source: &str) -> Result<Vec<IR1>, PartialCompilation> {
+        let x = Parser::create(source);
         let root = x.parse()?;
         let typeck = TypeChecker::new().check(root)?;
         let ir0_seq = typeck.into_ir();
diff --git a/package/origlang-compiler-scanner-example/src/lib.rs b/package/origlang-compiler-scanner-example/src/lib.rs
index c95c892..2dba939 100644
--- a/package/origlang-compiler-scanner-example/src/lib.rs
+++ b/package/origlang-compiler-scanner-example/src/lib.rs
@@ -77,7 +77,7 @@ mod tests {
                 s.ir1_scanner.push(PreOrPost::Pre(Box::new(MyScanner)));
             })
             .register_diagnostic_receiver(Box::new(tdr))
-            .compile("var foo = 1i32\n".to_string());
+            .compile("var foo = 1i32\n");
 
         assert!(a.is_ok());
     }
diff --git a/package/origlang-interop/src/lib.rs b/package/origlang-interop/src/lib.rs
index d4902d1..bf815ba 100644
--- a/package/origlang-interop/src/lib.rs
+++ b/package/origlang-interop/src/lib.rs
@@ -35,6 +35,7 @@ struct PseudoStdout;
 
 impl OutputAccumulator for PseudoStdout {
     fn output(&mut self, tb: TypeBox) {
+        // TODO: this shall be Box<str> whenever possible.
         let s: String = match tb {
             TypeBox::NonCoercedInteger(x) => x.to_string(),
             TypeBox::Int8(i) => i.to_string(),
diff --git a/package/origlang-lexer/src/tests.rs b/package/origlang-lexer/src/tests.rs
index 9f291a6..23fa8ac 100644
--- a/package/origlang-lexer/src/tests.rs
+++ b/package/origlang-lexer/src/tests.rs
@@ -9,11 +9,11 @@ fn test(str_lit: &str) {
     assert_eq!(
         p.next().data,
         Token::Identifier {
-            inner: Identifier::new("x".to_string()),
+            inner: Identifier::new("x".to_string().into_boxed_str()),
         }
     );
     assert_eq!(p.next().data, Token::SymEq);
-    assert_eq!(p.next().data, Token::StringLiteral(str_lit.to_string()));
+    assert_eq!(p.next().data, Token::StringLiteral(str_lit.to_string().into_boxed_str()));
 }
 
 #[test]
@@ -117,7 +117,7 @@ fn token_location() {
         lexer.next(),
         Pointed {
             data: Token::Identifier {
-                inner: Identifier::new("x".to_string())
+                inner: Identifier::new("x".to_string().into_boxed_str())
             },
             position: SourcePosition::try_new((1, 5)).unwrap()
         }
@@ -162,7 +162,7 @@ fn token_location() {
         lexer.next(),
         Pointed {
             data: Token::Identifier {
-                inner: Identifier::new("y".to_string())
+                inner: Identifier::new("y".to_string().into_boxed_str())
             },
             position: SourcePosition::try_new((2, 5)).unwrap()
         }
diff --git a/package/origlang-runtime/src/tests.rs b/package/origlang-runtime/src/tests.rs
index 80e1f34..f4c7f58 100644
--- a/package/origlang-runtime/src/tests.rs
+++ b/package/origlang-runtime/src/tests.rs
@@ -6,7 +6,7 @@ mod display {
         #[test]
         fn empty() {
             let x = DisplayRecordValue {
-                name: Identifier::new("abcdef".to_string()),
+                name: Identifier::new("abcdef".to_string().into_boxed_str()),
                 values: vec![],
             };
 
@@ -17,9 +17,9 @@ mod display {
         #[test]
         fn one() {
             let x = DisplayRecordValue {
-                name: Identifier::new("abcdef".to_string()),
+                name: Identifier::new("abcdef".to_string().into_boxed_str()),
                 values: vec![
-                    TypeBox::String("defg".to_string())
+                    TypeBox::String("defg".to_string().into_boxed_str())
                 ],
             };
 
@@ -30,11 +30,11 @@ mod display {
         #[test]
         fn many() {
             let x = DisplayRecordValue {
-                name: Identifier::new("abcdef".to_string()),
+                name: Identifier::new("abcdef".to_string().into_boxed_str()),
                 values: vec![
-                    TypeBox::String("abcdef".to_string()),
-                    TypeBox::String("ghijkl".to_string()),
-                    TypeBox::String("alice".to_string())
+                    TypeBox::String("abcdef".to_string().into_boxed_str()),
+                    TypeBox::String("ghijkl".to_string().into_boxed_str()),
+                    TypeBox::String("alice".to_string().into_boxed_str())
                 ],
             };
 
@@ -59,7 +59,7 @@ mod display {
         #[test]
         fn one() {
             let x = DisplayTupleValue {
-                boxes: Box::new([TypeBox::String("abcd".to_string())]),
+                boxes: Box::new([TypeBox::String("abcd".to_string().into_boxed_str())]),
             };
 
             let x = format!("{x}");
@@ -69,7 +69,7 @@ mod display {
         #[test]
         fn many() {
             let x = DisplayTupleValue {
-                boxes: Box::new([TypeBox::String("abcd".to_string()), TypeBox::String("defg".to_string())]),
+                boxes: Box::new([TypeBox::String("abcd".to_string().into_boxed_str()), TypeBox::String("defg".to_string().into_boxed_str())]),
             };
 
             let x = format!("{x}");
diff --git a/package/origlang-typecheck/src/type_check.rs b/package/origlang-typecheck/src/type_check.rs
index e84cd88..bbdda4a 100644
--- a/package/origlang-typecheck/src/type_check.rs
+++ b/package/origlang-typecheck/src/type_check.rs
@@ -208,7 +208,7 @@ impl TryIntoTypeCheckedForm for Expression {
                     }
                 } else {
                     Err(TypeCheckError::GenericTypeMismatch {
-                        context: "The condition of if-expression".to_string(),
+                        context: "The condition of if-expression".to_string().into_boxed_str(),
                         expected_type: Type::Boolean,
                         actual_type: cond_type,
                     })
@@ -490,7 +490,7 @@ impl TryIntoTypeCheckedForm for Statement {
                     }])
                 } else {
                     Err(TypeCheckError::GenericTypeMismatch {
-                        context: "variable assignment".to_string(),
+                        context: "variable assignment".to_string().into_boxed_str(),
                         expected_type,
                         actual_type: checked.actual_type(),
                     })
diff --git a/package/origlang-typecheck/src/type_check/error.rs b/package/origlang-typecheck/src/type_check/error.rs
index ca9b97f..a04d176 100644
--- a/package/origlang-typecheck/src/type_check/error.rs
+++ b/package/origlang-typecheck/src/type_check/error.rs
@@ -30,7 +30,7 @@ pub enum TypeCheckError {
     },
     #[error("{context} must be {expected_type}, got {actual_type}")]
     GenericTypeMismatch {
-        context: String,
+        context: Box<str>,
         expected_type: Type,
         actual_type: Type,
     },