diff --git a/libs/braillify/src/fraction.rs b/libs/braillify/src/fraction.rs
index a6d71cd..78b8514 100644
--- a/libs/braillify/src/fraction.rs
+++ b/libs/braillify/src/fraction.rs
@@ -94,12 +94,9 @@ fn read_braced_content(iter: &mut std::iter::Peekable<std::str::Chars>) -> Optio
                 iter.next();
             }
             _ => {
-                if let Some(digit) = normalize_digit(*c) {
-                    content.push(digit);
-                    iter.next();
-                } else {
-                    return None;
-                }
+                let digit = normalize_digit(*c)?;
+                content.push(digit);
+                iter.next();
             }
         }
     }
diff --git a/libs/braillify/src/rules/english_ueb/engine.rs b/libs/braillify/src/rules/english_ueb/engine.rs
index d8a700c..809e833 100644
--- a/libs/braillify/src/rules/english_ueb/engine.rs
+++ b/libs/braillify/src/rules/english_ueb/engine.rs
@@ -4244,10 +4244,9 @@ fn push_spatial_char(out: &mut Vec<u8>, c: char) -> Option<()> {
         out.extend([CAPITAL, decode_unicode('⠜')]);
     } else if c == '<' {
         out.extend([CAPITAL, decode_unicode('⠣')]);
-    } else if let Some(cells) = super::rule_16::spatial_symbol(c) {
-        out.extend(cells);
     } else {
-        return None;
+        let cells = super::rule_16::spatial_symbol(c)?;
+        out.extend(cells);
     }
     Some(())
 }
diff --git a/libs/braillify/src/rules/english_ueb/rule_11.rs b/libs/braillify/src/rules/english_ueb/rule_11.rs
index 74bead5..df1df47 100644
--- a/libs/braillify/src/rules/english_ueb/rule_11.rs
+++ b/libs/braillify/src/rules/english_ueb/rule_11.rs
@@ -330,7 +330,7 @@ fn encode_expr_with_options(
             let (next, item) = if chars.get(i) == Some(&'{') {
                 take_braced(chars, i)?
             } else {
-                (i + 1, &chars[i..i + 1])
+                (i + 1, chars.get(i..i + 1)?)
             };
             let need_grouping = item_needs_braille_grouping(item);
             if need_grouping {
@@ -736,6 +736,13 @@ mod tests {
         assert_eq!(encode_technical(&"@".chars().collect::<Vec<_>>()), None);
     }
 
+    #[rstest::rstest]
+    #[case::dangling_superscript('^')]
+    #[case::dangling_subscript('_')]
+    fn rejects_dangling_script_marker_without_panicking(#[case] marker: char) {
+        assert_eq!(encode_technical(&[marker]), None);
+    }
+
     #[test]
     fn helper_primitives_reject_invalid_inputs() {
         let mut out = Vec::new();
diff --git a/package.json b/package.json
index 01704bf..02c8b4e 100644
--- a/package.json
+++ b/package.json
@@ -7,7 +7,10 @@
   "scripts": {
     "lint": "oxlint . && cargo fmt --all -- --check && cargo clippy --workspace --all-targets -- -D warnings",
     "lint:fix": "oxlint . --fix && cargo fmt --all && cargo clippy --workspace --all-targets --fix --allow-dirty --allow-staged -- -D warnings && cargo clippy --workspace --all-targets -- -D warnings",
-    "test": "cargo tarpaulin --engine llvm --out xml --out stdout -- --skip test_by_testcase && bun test --coverage && cd py-test && uv run pytest",
+    "test": "bun run test:rust && bun run test:node && bun run test:python",
+    "test:rust": "cargo tarpaulin --engine llvm --out xml --out stdout -- --skip test_by_testcase",
+    "test:node": "bun test --coverage",
+    "test:python": "cd py-test && uv run --locked pytest",
     "test:testcase": "cargo test -p braillify test_by_testcase -- --nocapture",
     "preinstall": "uv sync && (cargo install wasm-pack || node -e \"process.exit(0)\") && (pip install maturin || \"process.exit(0)\")",
     "build": "cargo build --release -p braillify && bun -F braillify build && cd packages/python && maturin build --release --out dist",
diff --git a/py-test/pyproject.toml b/py-test/pyproject.toml
index 25816da..9d003b4 100644
--- a/py-test/pyproject.toml
+++ b/py-test/pyproject.toml
@@ -4,7 +4,7 @@ version = "0.1.0"
 description = ""
 authors = [{ name = "owjs3901", email = "owjs3901@gmail.com" }]
 readme = "README.md"
-requires-python = ">=3.13"
+requires-python = ">=3.11"
 dependencies = ["braillify"]
 
 [tool.uv.sources]
diff --git a/pyproject.toml b/pyproject.toml
index af6934b..7328d22 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ version = "0.1.0"
 description = ""
 authors = [{ name = "owjs3901", email = "owjs3901@gmail.com" }]
 readme = "README.md"
-requires-python = ">=3.13"
+requires-python = ">=3.11"
 
 [tool.uv.workspace]
 members = ["packages/python", "py-test"]
diff --git a/uv.lock b/uv.lock
index 2ba0b4a..447865b 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1,6 +1,6 @@
 version = 1
 revision = 3
-requires-python = ">=3.13"
+requires-python = ">=3.11"
 
 [manifest]
 members = [