diff --git a/crates/aiken-lang/src/builtins.rs b/crates/aiken-lang/src/builtins.rs
index 06a2f859..5c841b71 100644
--- a/crates/aiken-lang/src/builtins.rs
+++ b/crates/aiken-lang/src/builtins.rs
@@ -505,10 +505,13 @@ pub fn plutus(id_gen: &IdGenerator) -> TypeInfo {
         annotations: HashMap::new(),
     };
 
-    for builtin in DefaultFunction::iter().take(75) {
-        let value = from_default_function(builtin, id_gen);
-
-        plutus.values.insert(builtin.aiken_name(), value);
+    for builtin in DefaultFunction::iter() {
+        // FIXME: Disabling WriteBits for now, since its signature requires the ability to create
+        // list of raw integers, which isn't possible through Aiken at the moment.
+        if !matches!(builtin, DefaultFunction::WriteBits) {
+            let value = from_default_function(builtin, id_gen);
+            plutus.values.insert(builtin.aiken_name(), value);
+        }
     }
 
     plutus
diff --git a/crates/aiken-lang/src/gen_uplc.rs b/crates/aiken-lang/src/gen_uplc.rs
index e03e6407..c38fa805 100644
--- a/crates/aiken-lang/src/gen_uplc.rs
+++ b/crates/aiken-lang/src/gen_uplc.rs
@@ -44,7 +44,6 @@ use builder::{
     introduce_name, introduce_pattern, pop_pattern, softcast_data_to_type_otherwise,
     unknown_data_to_type, DISCARDED,
 };
-
 use decision_tree::{get_tipo_by_path, Assigned, CaseTest, DecisionTree, TreeGen};
 use indexmap::IndexMap;
 use interner::AirInterner;
diff --git a/crates/uplc/src/machine/error.rs b/crates/uplc/src/machine/error.rs
index 5c132bb5..3df2e519 100644
--- a/crates/uplc/src/machine/error.rs
+++ b/crates/uplc/src/machine/error.rs
@@ -136,6 +136,8 @@ pub enum Error {
     ReadBitOutOfBounds,
     #[error("writeBits: index out of bounds")]
     WriteBitsOutOfBounds,
+    #[error("illegal operation on empty ByteArray")]
+    EmptyByteArray,
     #[error("blst error {0:?}")]
     Blst(blst::BLST_ERROR),
     #[error("blst::hashToGroup")]
diff --git a/crates/uplc/src/machine/runtime.rs b/crates/uplc/src/machine/runtime.rs
index 8b101a09..faeef8d4 100644
--- a/crates/uplc/src/machine/runtime.rs
+++ b/crates/uplc/src/machine/runtime.rs
@@ -1592,6 +1592,10 @@ impl DefaultFunction {
                 let bytes = args[0].unwrap_byte_string()?;
                 let bit_index = args[1].unwrap_integer()?;
 
+                if bytes.is_empty() {
+                    return Err(Error::EmptyByteArray);
+                }
+
                 // This ensures there is at least one byte in bytes
                 if *bit_index < 0.into() || *bit_index >= (bytes.len() * 8).into() {
                     return Err(Error::ReadBitOutOfBounds);