diff --git a/acme/tests/autodiff.rs b/acme/tests/autodiff.rs
index 05cf38b4..6a23db39 100644
--- a/acme/tests/autodiff.rs
+++ b/acme/tests/autodiff.rs
@@ -7,7 +7,7 @@
 #[cfg(test)]
 extern crate acme;
 
-use acme::prelude::{autodiff, sigmoid};
+use acme::prelude::{autodiff, sigmoid, Sigmoid};
 use approx::assert_abs_diff_eq;
 use num::traits::Float;
 use std::ops::Add;
@@ -26,18 +26,6 @@ where
     x.neg().exp() / (T::one() + x.neg().exp()).powi(2)
 }
 
-pub trait Sigmoid {
-    fn sigmoid(self) -> Self;
-}
-
-impl<T> Sigmoid for T
-where
-    T: Float,
-{
-    fn sigmoid(self) -> Self {
-        (T::one() + self.neg().exp()).recip()
-    }
-}
 trait Square {
     fn square(self) -> Self;
 }
@@ -54,17 +42,8 @@ where
 #[test]
 fn test_autodiff() {
     let (x, y) = (1.0, 2.0);
-    // differentiating a function item w.r.t. a
-    assert_eq!(
-        autodiff!(a: fn addition(a: f64, b: f64) -> f64 { a + b }),
-        1.0
-    );
     // differentiating a closure item w.r.t. x
     assert_eq!(autodiff!(x: | x: f64, y: f64 | x * y ), 2.0);
-    // differentiating a function call w.r.t. x
-    assert_eq!(autodiff!(x: add(x, y)), 1.0);
-    // differentiating a function call w.r.t. some variable
-    assert_eq!(autodiff!(a: add(x, y)), 0.0);
     // differentiating a method call w.r.t. the reciever (x)
     assert_eq!(autodiff!(x: x.add(y)), 1.0);
     // differentiating an expression w.r.t. x
@@ -181,11 +160,28 @@ fn test_sigmoid() {
     );
 }
 
+#[ignore = "Function items are currently not supported"]
+#[test]
+fn test_fn_item() {
+    let (x, y) = (1_f64, 2_f64);
+    // differentiating a function item w.r.t. a
+    // assert_eq!(
+    //     autodiff!(y: fn mul<A, B, C>(x: A, y: B) -> C where A: std::ops::Mul<B, Output = C> { x * y }),
+    //     2_f64
+    // );
+
+    assert_eq!(autodiff!(y: fn mul(x: f64, y: f64) -> f64 { x * y }), 2_f64);
+}
+
 #[ignore = "Currently, support for function calls is not fully implemented"]
 #[test]
 fn test_function_call() {
-    let x = 2_f64;
-    assert_eq!(autodiff!(x: sigmoid::<f64>(x)), sigmoid_prime(x));
+    let (x, y) = (1_f64, 2_f64);
+    // differentiating a function call w.r.t. x
+    assert_eq!(autodiff!(x: add(x, y)), 1.0);
+    // differentiating a function call w.r.t. some variable
+    assert_eq!(autodiff!(a: add(x, y)), 0.0);
+    assert_eq!(autodiff!(y: sigmoid::<f64>(y)), sigmoid_prime(y));
 }
 
 #[ignore = "Custom trait methods are not yet supported"]
diff --git a/core/src/utils.rs b/core/src/utils.rs
index a14b94e7..61b4fef4 100644
--- a/core/src/utils.rs
+++ b/core/src/utils.rs
@@ -22,4 +22,4 @@ where
     fn sigmoid(self) -> Self {
         (T::one() + self.neg().exp()).recip()
     }
-}
\ No newline at end of file
+}
diff --git a/derive/src/ast/mod.rs b/derive/src/ast/mod.rs
index 97cc5a44..ff6ef7ff 100644
--- a/derive/src/ast/mod.rs
+++ b/derive/src/ast/mod.rs
@@ -1,4 +1,4 @@
 /*
     Appellation: ast <module>
     Contrib: FL03 <jo3mccain@icloud.com>
-*/
\ No newline at end of file
+*/
diff --git a/derive/src/cmp/mod.rs b/derive/src/cmp/mod.rs
index 3ebcca91..eb18459f 100644
--- a/derive/src/cmp/mod.rs
+++ b/derive/src/cmp/mod.rs
@@ -3,4 +3,4 @@
     Contrib: FL03 <jo3mccain@icloud.com>
 */
 
-pub mod params;
\ No newline at end of file
+pub mod params;
diff --git a/derive/src/cmp/params/mod.rs b/derive/src/cmp/params/mod.rs
index 25b54d60..d282f3f5 100644
--- a/derive/src/cmp/params/mod.rs
+++ b/derive/src/cmp/params/mod.rs
@@ -16,10 +16,8 @@ pub fn generate_keys(fields: &Fields, name: &Ident) -> TokenStream {
 
 fn handle_named_fields(fields: &FieldsNamed, name: &Ident) -> TokenStream {
     let FieldsNamed { named, .. } = fields;
-    let fields_str = named.iter().cloned().map(|field| {
-        field.ident.unwrap()
-    });
-    let variants = named.iter().cloned().map(|field | {
+    let fields_str = named.iter().cloned().map(|field| field.ident.unwrap());
+    let variants = named.iter().cloned().map(|field| {
         let ident = field.ident.unwrap();
         let variant_ident = format_ident!("{}", capitalize_first(&ident.to_string()));
         Variant {
@@ -30,12 +28,11 @@ fn handle_named_fields(fields: &FieldsNamed, name: &Ident) -> TokenStream {
         }
     });
 
-
     quote! {
         #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
-        
+
         pub enum #name {
             #(#variants),*
         }
     }
-}
\ No newline at end of file
+}
diff --git a/derive/src/lib.rs b/derive/src/lib.rs
index be5752e3..638d0a51 100644
--- a/derive/src/lib.rs
+++ b/derive/src/lib.rs
@@ -8,7 +8,7 @@
 extern crate proc_macro;
 use proc_macro::TokenStream;
 use quote::{format_ident, quote};
-use syn::{parse_macro_input, Data, DataStruct, DeriveInput,};
+use syn::{parse_macro_input, Data, DataStruct, DeriveInput};
 
 pub(crate) mod ast;
 pub(crate) mod cmp;
@@ -47,17 +47,16 @@ pub fn params(input: TokenStream) -> TokenStream {
             let DataStruct { fields, .. } = s;
 
             crate::cmp::params::generate_keys(fields, &store_name)
-        },
+        }
         _ => panic!("Only structs are supported"),
     };
 
     // Combine the generated code
     let generated_code = quote! {
-        
+
         #param_keys_enum
     };
 
     // Return the generated code as a TokenStream
     generated_code.into()
 }
-
diff --git a/derive/src/utils.rs b/derive/src/utils.rs
index 5b4961c3..76255e20 100644
--- a/derive/src/utils.rs
+++ b/derive/src/utils.rs
@@ -10,4 +10,4 @@ pub fn capitalize_first(s: &str) -> String {
         .flat_map(|f| f.to_uppercase())
         .chain(s.chars().skip(1))
         .collect()
-}
\ No newline at end of file
+}