diff --git a/crates/env/src/api.rs b/crates/env/src/api.rs
index 065d4112978..b5d351448de 100644
--- a/crates/env/src/api.rs
+++ b/crates/env/src/api.rs
@@ -21,7 +21,6 @@ use crate::{
         TypedEnvBackend,
     },
     call::{
-        utils::ReturnType,
         CallParams,
         CreateParams,
     },
@@ -216,33 +215,7 @@ pub fn clear_contract_storage(key: &Key) {
     })
 }
 
-/// Invokes a contract message.
-///
-/// # Note
-///
-/// - Prefer using this over [`eval_contract`] if possible. [`invoke_contract`]
-///   will generally have a better performance since it won't try to fetch any results.
-/// - This is a low level way to invoke another smart contract.
-///   Prefer to use the ink! guided and type safe approach to using this.
-///
-/// # Errors
-///
-/// - If the called account does not exist.
-/// - If the called account is not a contract.
-/// - If arguments passed to the called contract message are invalid.
-/// - If the called contract execution has trapped.
-/// - If the called contract ran out of gas upon execution.
-pub fn invoke_contract<T, Args>(params: &CallParams<T, Args, ()>) -> Result<()>
-where
-    T: Environment,
-    Args: scale::Encode,
-{
-    <EnvInstance as OnInstance>::on_instance(|instance| {
-        TypedEnvBackend::invoke_contract::<T, Args>(instance, params)
-    })
-}
-
-/// Evaluates a contract message and returns its result.
+/// Invokes a contract message and returns its result.
 ///
 /// # Note
 ///
@@ -257,14 +230,14 @@ where
 /// - If the called contract execution has trapped.
 /// - If the called contract ran out of gas upon execution.
 /// - If the returned value failed to decode properly.
-pub fn eval_contract<T, Args, R>(params: &CallParams<T, Args, ReturnType<R>>) -> Result<R>
+pub fn invoke_contract<T, Args, R>(params: &CallParams<T, Args, R>) -> Result<R>
 where
     T: Environment,
     Args: scale::Encode,
     R: scale::Decode,
 {
     <EnvInstance as OnInstance>::on_instance(|instance| {
-        TypedEnvBackend::eval_contract::<T, Args, R>(instance, params)
+        TypedEnvBackend::invoke_contract::<T, Args, R>(instance, params)
     })
 }
 
diff --git a/crates/env/src/backend.rs b/crates/env/src/backend.rs
index 7182d6ad9a8..5fed490a2c9 100644
--- a/crates/env/src/backend.rs
+++ b/crates/env/src/backend.rs
@@ -14,7 +14,6 @@
 
 use crate::{
     call::{
-        utils::ReturnType,
         CallParams,
         CreateParams,
     },
@@ -359,27 +358,14 @@ pub trait TypedEnvBackend: EnvBackend {
         T: Environment,
         Event: Topics + scale::Encode;
 
-    /// Invokes a contract message.
+    /// Invokes a contract message and returns its result.
     ///
     /// # Note
     ///
     /// For more details visit: [`invoke_contract`][`crate::invoke_contract`]
-    fn invoke_contract<T, Args>(
+    fn invoke_contract<T, Args, R>(
         &mut self,
-        call_data: &CallParams<T, Args, ()>,
-    ) -> Result<()>
-    where
-        T: Environment,
-        Args: scale::Encode;
-
-    /// Evaluates a contract message and returns its result.
-    ///
-    /// # Note
-    ///
-    /// For more details visit: [`eval_contract`][`crate::eval_contract`]
-    fn eval_contract<T, Args, R>(
-        &mut self,
-        call_data: &CallParams<T, Args, ReturnType<R>>,
+        call_data: &CallParams<T, Args, R>,
     ) -> Result<R>
     where
         T: Environment,
diff --git a/crates/env/src/call/call_builder.rs b/crates/env/src/call/call_builder.rs
index b7a37a1177e..3bef7651301 100644
--- a/crates/env/src/call/call_builder.rs
+++ b/crates/env/src/call/call_builder.rs
@@ -84,38 +84,17 @@ where
     }
 }
 
-impl<E, Args> CallParams<E, Args, ()>
-where
-    E: Environment,
-    Args: scale::Encode,
-{
-    /// Invokes the contract with the given built-up call parameters.
-    ///
-    /// # Note
-    ///
-    /// Prefer [`invoke`](`Self::invoke`) over [`eval`](`Self::eval`) if the
-    /// called contract message does not return anything because it is more efficient.
-    pub fn invoke(&self) -> Result<(), crate::Error> {
-        crate::invoke_contract(self)
-    }
-}
-
-impl<E, Args, R> CallParams<E, Args, ReturnType<R>>
+impl<E, Args, R> CallParams<E, Args, R>
 where
     E: Environment,
     Args: scale::Encode,
     R: scale::Decode,
 {
-    /// Evaluates the contract with the given built-up call parameters.
+    /// Invokes the contract with the given built-up call parameters.
     ///
     /// Returns the result of the contract execution.
-    ///
-    /// # Note
-    ///
-    /// Prefer [`invoke`](`Self::invoke`) over [`eval`](`Self::eval`) if the
-    /// called contract message does not return anything because it is more efficient.
-    pub fn eval(&self) -> Result<R, crate::Error> {
-        crate::eval_contract(self)
+    pub fn invoke(&self) -> Result<R, crate::Error> {
+        crate::invoke_contract(self)
     }
 }
 
@@ -179,7 +158,7 @@ where
 /// # use ::ink_env::{
 /// #     Environment,
 /// #     DefaultEnvironment,
-/// #     call::{build_call, Selector, ExecutionInput, utils::ReturnType},
+/// #     call::{build_call, Selector, ExecutionInput},
 /// # };
 /// # type AccountId = <DefaultEnvironment as Environment>::AccountId;
 /// let my_return_value: i32 = build_call::<DefaultEnvironment>()
@@ -192,7 +171,7 @@ where
 ///             .push_arg(true)
 ///             .push_arg(&[0x10; 32])
 ///     )
-///     .returns::<ReturnType<i32>>()
+///     .returns::<i32>()
 ///     .fire()
 ///     .unwrap();
 /// ```
@@ -328,18 +307,6 @@ where
     }
 }
 
-mod seal {
-    /// Used to prevent users from implementing `IndicateReturnType` for their own types.
-    pub trait Sealed {}
-    impl Sealed for () {}
-    impl<T> Sealed for super::ReturnType<T> {}
-}
-
-/// Types that can be used in [`CallBuilder::returns`] to signal return type.
-pub trait IndicateReturnType: Default + self::seal::Sealed {}
-impl IndicateReturnType for () {}
-impl<T> IndicateReturnType for ReturnType<T> {}
-
 impl<E, Callee, GasLimit, TransferredValue, Args>
     CallBuilder<E, Callee, GasLimit, TransferredValue, Args, Unset<ReturnType<()>>>
 where
@@ -350,14 +317,11 @@ where
     /// # Note
     ///
     /// Either use `.returns::<()>` to signal that the call does not return a value
-    /// or use `.returns::<ReturnType<T>>` to signal that the call returns a value of
-    /// type `T`.
+    /// or use `.returns::<T>` to signal that the call returns a value of type `T`.
     #[inline]
     pub fn returns<R>(
         self,
-    ) -> CallBuilder<E, Callee, GasLimit, TransferredValue, Args, Set<R>>
-    where
-        R: IndicateReturnType,
+    ) -> CallBuilder<E, Callee, GasLimit, TransferredValue, Args, Set<ReturnType<R>>>
     {
         CallBuilder {
             env: Default::default(),
@@ -414,7 +378,7 @@ impl<E, GasLimit, TransferredValue, Args, RetType>
         GasLimit,
         TransferredValue,
         Set<ExecutionInput<Args>>,
-        Set<RetType>,
+        Set<ReturnType<RetType>>,
     >
 where
     E: Environment,
@@ -465,27 +429,6 @@ where
     }
 }
 
-impl<E, GasLimit, TransferredValue, Args>
-    CallBuilder<
-        E,
-        Set<E::AccountId>,
-        GasLimit,
-        TransferredValue,
-        Set<ExecutionInput<Args>>,
-        Set<()>,
-    >
-where
-    E: Environment,
-    GasLimit: Unwrap<Output = u64>,
-    Args: scale::Encode,
-    TransferredValue: Unwrap<Output = E::Balance>,
-{
-    /// Invokes the cross-chain function call.
-    pub fn fire(self) -> Result<(), Error> {
-        self.params().invoke()
-    }
-}
-
 impl<E, GasLimit, TransferredValue>
     CallBuilder<
         E,
@@ -524,6 +467,6 @@ where
 {
     /// Invokes the cross-chain function call and returns the result.
     pub fn fire(self) -> Result<R, Error> {
-        self.params().eval()
+        self.params().invoke()
     }
 }
diff --git a/crates/env/src/call/common.rs b/crates/env/src/call/common.rs
index 94cf6c7bfcb..e1cc4171a2d 100644
--- a/crates/env/src/call/common.rs
+++ b/crates/env/src/call/common.rs
@@ -18,7 +18,7 @@ use core::marker::PhantomData;
 
 /// Represents a return type.
 ///
-/// Used as a marker type to differentiate at compile-time between invoke and evaluate.
+/// Used as a marker type to define the return type of an ink! message in call builders.
 #[derive(Debug)]
 pub struct ReturnType<T>(PhantomData<fn() -> T>);
 
diff --git a/crates/env/src/call/mod.rs b/crates/env/src/call/mod.rs
index 7cb8c4fa97c..a4c6fa653f8 100644
--- a/crates/env/src/call/mod.rs
+++ b/crates/env/src/call/mod.rs
@@ -23,7 +23,6 @@ mod selector;
 /// Utility types for the cross-contract calling API.
 pub mod utils {
     pub use super::{
-        call_builder::IndicateReturnType,
         common::{
             ReturnType,
             Set,
diff --git a/crates/env/src/engine/off_chain/impls.rs b/crates/env/src/engine/off_chain/impls.rs
index 2ecf10a0acd..d8a98edb6a5 100644
--- a/crates/env/src/engine/off_chain/impls.rs
+++ b/crates/env/src/engine/off_chain/impls.rs
@@ -15,7 +15,6 @@
 use super::EnvInstance;
 use crate::{
     call::{
-        utils::ReturnType,
         CallParams,
         CreateParams,
     },
@@ -387,10 +386,14 @@ impl TypedEnvBackend for EnvInstance {
         self.engine.deposit_event(&enc_topics[..], enc_data);
     }
 
-    fn invoke_contract<T, Args>(&mut self, params: &CallParams<T, Args, ()>) -> Result<()>
+    fn invoke_contract<T, Args, R>(
+        &mut self,
+        params: &CallParams<T, Args, R>,
+    ) -> Result<R>
     where
         T: Environment,
         Args: scale::Encode,
+        R: scale::Decode,
     {
         let _gas_limit = params.gas_limit();
         let _callee = params.callee();
@@ -400,18 +403,6 @@ impl TypedEnvBackend for EnvInstance {
         unimplemented!("off-chain environment does not support contract invocation")
     }
 
-    fn eval_contract<T, Args, R>(
-        &mut self,
-        _call_params: &CallParams<T, Args, ReturnType<R>>,
-    ) -> Result<R>
-    where
-        T: Environment,
-        Args: scale::Encode,
-        R: scale::Decode,
-    {
-        unimplemented!("off-chain environment does not support contract evaluation")
-    }
-
     fn instantiate_contract<T, Args, Salt, C>(
         &mut self,
         params: &CreateParams<T, Args, Salt, C>,
diff --git a/crates/env/src/engine/on_chain/impls.rs b/crates/env/src/engine/on_chain/impls.rs
index 4ee4b5e0864..548bf0dab7e 100644
--- a/crates/env/src/engine/on_chain/impls.rs
+++ b/crates/env/src/engine/on_chain/impls.rs
@@ -20,7 +20,6 @@ use super::{
 };
 use crate::{
     call::{
-        utils::ReturnType,
         CallParams,
         CreateParams,
     },
@@ -215,45 +214,6 @@ impl EnvInstance {
         ext_fn(full_scope);
         scale::Decode::decode(&mut &full_scope[..]).map_err(Into::into)
     }
-
-    /// Reusable implementation for invoking another contract message.
-    fn invoke_contract_impl<T, Args, RetType, R>(
-        &mut self,
-        params: &CallParams<T, Args, RetType>,
-    ) -> Result<R>
-    where
-        T: Environment,
-        Args: scale::Encode,
-        R: scale::Decode,
-    {
-        let mut scope = self.scoped_buffer();
-        let gas_limit = params.gas_limit();
-        let enc_callee = scope.take_encoded(params.callee());
-        let enc_transferred_value = scope.take_encoded(params.transferred_value());
-        let call_flags = params.call_flags();
-        let enc_input = if !call_flags.forward_input() && !call_flags.clone_input() {
-            scope.take_encoded(params.exec_input())
-        } else {
-            &mut []
-        };
-        let output = &mut scope.take_rest();
-        let flags = params.call_flags().into_u32();
-        let call_result = ext::call(
-            flags,
-            enc_callee,
-            gas_limit,
-            enc_transferred_value,
-            enc_input,
-            output,
-        );
-        match call_result {
-            Ok(()) | Err(ext::Error::CalleeReverted) => {
-                let decoded = scale::Decode::decode(&mut &output[..])?;
-                Ok(decoded)
-            }
-            Err(actual_error) => Err(actual_error.into()),
-        }
-    }
 }
 
 impl EnvBackend for EnvInstance {
@@ -396,27 +356,42 @@ impl TypedEnvBackend for EnvInstance {
         ext::deposit_event(enc_topics, enc_data);
     }
 
-    fn invoke_contract<T, Args>(
+    fn invoke_contract<T, Args, R>(
         &mut self,
-        call_params: &CallParams<T, Args, ()>,
-    ) -> Result<()>
-    where
-        T: Environment,
-        Args: scale::Encode,
-    {
-        self.invoke_contract_impl(call_params)
-    }
-
-    fn eval_contract<T, Args, R>(
-        &mut self,
-        call_params: &CallParams<T, Args, ReturnType<R>>,
+        params: &CallParams<T, Args, R>,
     ) -> Result<R>
     where
         T: Environment,
         Args: scale::Encode,
         R: scale::Decode,
     {
-        self.invoke_contract_impl(call_params)
+        let mut scope = self.scoped_buffer();
+        let gas_limit = params.gas_limit();
+        let enc_callee = scope.take_encoded(params.callee());
+        let enc_transferred_value = scope.take_encoded(params.transferred_value());
+        let call_flags = params.call_flags();
+        let enc_input = if !call_flags.forward_input() && !call_flags.clone_input() {
+            scope.take_encoded(params.exec_input())
+        } else {
+            &mut []
+        };
+        let output = &mut scope.take_rest();
+        let flags = params.call_flags().into_u32();
+        let call_result = ext::call(
+            flags,
+            enc_callee,
+            gas_limit,
+            enc_transferred_value,
+            enc_input,
+            output,
+        );
+        match call_result {
+            Ok(()) | Err(ext::Error::CalleeReverted) => {
+                let decoded = scale::Decode::decode(&mut &output[..])?;
+                Ok(decoded)
+            }
+            Err(actual_error) => Err(actual_error.into()),
+        }
     }
 
     fn instantiate_contract<T, Args, Salt, C>(
diff --git a/crates/lang/codegen/src/generator/as_dependency/call_builder.rs b/crates/lang/codegen/src/generator/as_dependency/call_builder.rs
index 57750e47a84..757d15ae2f5 100644
--- a/crates/lang/codegen/src/generator/as_dependency/call_builder.rs
+++ b/crates/lang/codegen/src/generator/as_dependency/call_builder.rs
@@ -372,10 +372,8 @@ impl CallBuilder<'_> {
         let arg_list = generator::generate_argument_list(input_types.iter().cloned());
         let mut_tok = callable.receiver().is_ref_mut().then(|| quote! { mut });
         let output = message.output();
-        let output_sig = output.map_or_else(
-            || quote! { () },
-            |output| quote! { ::ink_env::call::utils::ReturnType<#output> },
-        );
+        let return_type =
+            output.map_or_else(|| quote! { () }, |output| quote! { #output });
         let output_span = output.span();
         let output_type = quote_spanned!(output_span=>
             ::ink_env::call::CallBuilder<
@@ -384,7 +382,7 @@ impl CallBuilder<'_> {
                 ::ink_env::call::utils::Unset< ::core::primitive::u64 >,
                 ::ink_env::call::utils::Unset< <Environment as ::ink_env::Environment>::Balance >,
                 ::ink_env::call::utils::Set< ::ink_env::call::ExecutionInput<#arg_list> >,
-                ::ink_env::call::utils::Set<#output_sig>,
+                ::ink_env::call::utils::Set< ::ink_env::call::utils::ReturnType<#return_type> >,
             >
         );
         quote_spanned!(span=>
@@ -405,7 +403,7 @@ impl CallBuilder<'_> {
                             .push_arg(#input_bindings)
                         )*
                     )
-                    .returns::<#output_sig>()
+                    .returns::<#return_type>()
             }
         )
     }
diff --git a/crates/lang/codegen/src/generator/trait_def/call_builder.rs b/crates/lang/codegen/src/generator/trait_def/call_builder.rs
index 3f820c98095..21414335e8b 100644
--- a/crates/lang/codegen/src/generator/trait_def/call_builder.rs
+++ b/crates/lang/codegen/src/generator/trait_def/call_builder.rs
@@ -365,10 +365,8 @@ impl CallBuilder<'_> {
             .filter_attr(message.attrs());
         let output_ident = generator::output_ident(message_ident);
         let output = message.output();
-        let output_sig = output.map_or_else(
-            || quote! { () },
-            |output| quote! { ::ink_env::call::utils::ReturnType<#output> },
-        );
+        let output_type =
+            output.map_or_else(|| quote! { () }, |output| quote! { #output });
         let selector_bytes = selector.hex_lits();
         let input_bindings = generator::input_bindings(message.inputs());
         let input_types = generator::input_types(message.inputs());
@@ -382,7 +380,7 @@ impl CallBuilder<'_> {
                 ::ink_env::call::utils::Unset< ::core::primitive::u64 >,
                 ::ink_env::call::utils::Unset< <Self::Env as ::ink_env::Environment>::Balance >,
                 ::ink_env::call::utils::Set< ::ink_env::call::ExecutionInput<#arg_list> >,
-                ::ink_env::call::utils::Set<#output_sig>,
+                ::ink_env::call::utils::Set< ::ink_env::call::utils::ReturnType<#output_type> >,
             >;
 
             #( #attrs )*
@@ -401,7 +399,7 @@ impl CallBuilder<'_> {
                             .push_arg(#input_bindings)
                         )*
                     )
-                    .returns::<#output_sig>()
+                    .returns::<#output_type>()
             }
         )
     }
diff --git a/crates/lang/src/env_access.rs b/crates/lang/src/env_access.rs
index 11ca46d40ef..572a529795a 100644
--- a/crates/lang/src/env_access.rs
+++ b/crates/lang/src/env_access.rs
@@ -16,7 +16,6 @@ use crate::ChainExtensionInstance;
 use core::marker::PhantomData;
 use ink_env::{
     call::{
-        utils::ReturnType,
         CallParams,
         CreateParams,
     },
@@ -504,7 +503,7 @@ where
         ink_env::instantiate_contract::<T, Args, Salt, C>(params)
     }
 
-    /// Invokes a contract message without fetching its result.
+    /// Invokes a contract message and returns its result.
     ///
     /// # Example
     ///
@@ -527,9 +526,9 @@ where
     /// #             Self {}
     /// #         }
     /// #
-    /// /// Invokes another contract message without fetching the result.
+    /// /// Invokes a contract message and fetches the result.
     /// #[ink(message)]
-    /// pub fn invoke_contract(&self) {
+    /// pub fn invoke_contract(&self) -> i32 {
     ///     let call_params = build_call::<DefaultEnvironment>()
     ///         .callee(AccountId::from([0x42; 32]))
     ///         .gas_limit(5000)
@@ -540,9 +539,9 @@ where
     ///                 .push_arg(true)
     ///                 .push_arg(&[0x10u8; 32])
     ///         )
-    ///         .returns::<()>()
+    ///         .returns::<i32>()
     ///         .params();
-    ///     self.env().invoke_contract(&call_params).expect("call invocation must succeed");
+    ///     self.env().invoke_contract(&call_params).expect("call invocation must succeed")
     /// }
     /// #
     /// #     }
@@ -552,70 +551,12 @@ where
     /// # Note
     ///
     /// For more details visit: [`ink_env::invoke_contract`]
-    pub fn invoke_contract<Args>(self, params: &CallParams<T, Args, ()>) -> Result<()>
-    where
-        Args: scale::Encode,
-    {
-        ink_env::invoke_contract::<T, Args>(params)
-    }
-
-    /// Evaluates a contract message and returns its result.
-    ///
-    /// # Example
-    ///
-    /// ```
-    /// # use ink_lang as ink;
-    /// # #[ink::contract]
-    /// # pub mod my_contract {
-    /// use ink_env::{
-    ///     DefaultEnvironment,
-    ///     call::{build_call, Selector, ExecutionInput, utils::ReturnType}
-    /// };
-    ///
-    /// #
-    /// #     #[ink(storage)]
-    /// #     pub struct MyContract { }
-    /// #
-    /// #     impl MyContract {
-    /// #         #[ink(constructor)]
-    /// #         pub fn new() -> Self {
-    /// #             Self {}
-    /// #         }
-    /// #
-    /// /// Evaluates a contract message and fetches the result.
-    /// #[ink(message)]
-    /// pub fn evaluate_contract(&self) -> i32 {
-    ///     let call_params = build_call::<DefaultEnvironment>()
-    ///         .callee(AccountId::from([0x42; 32]))
-    ///         .gas_limit(5000)
-    ///         .transferred_value(10)
-    ///         .exec_input(
-    ///             ExecutionInput::new(Selector::new([0xCA, 0xFE, 0xBA, 0xBE]))
-    ///                 .push_arg(42)
-    ///                 .push_arg(true)
-    ///                 .push_arg(&[0x10u8; 32])
-    ///         )
-    ///         .returns::<ReturnType<i32>>()
-    ///         .params();
-    ///     self.env().eval_contract(&call_params).expect("call invocation must succeed")
-    /// }
-    /// #
-    /// #     }
-    /// # }
-    /// ```
-    ///
-    /// # Note
-    ///
-    /// For more details visit: [`ink_env::eval_contract`]
-    pub fn eval_contract<Args, R>(
-        self,
-        params: &CallParams<T, Args, ReturnType<R>>,
-    ) -> Result<R>
+    pub fn invoke_contract<Args, R>(self, params: &CallParams<T, Args, R>) -> Result<R>
     where
         Args: scale::Encode,
         R: scale::Decode,
     {
-        ink_env::eval_contract::<T, Args, R>(params)
+        ink_env::invoke_contract::<T, Args, R>(params)
     }
 
     /// Terminates the existence of a contract.
diff --git a/crates/lang/tests/ui/contract/fail/message-input-non-codec.stderr b/crates/lang/tests/ui/contract/fail/message-input-non-codec.stderr
index 9299baed8f3..853f789bf6d 100644
--- a/crates/lang/tests/ui/contract/fail/message-input-non-codec.stderr
+++ b/crates/lang/tests/ui/contract/fail/message-input-non-codec.stderr
@@ -32,11 +32,11 @@ note: required by a bound in `ExecutionInput::<ArgumentList<ArgumentListEnd, Arg
    |         T: scale::Encode,
    |            ^^^^^^^^^^^^^ required by this bound in `ExecutionInput::<ArgumentList<ArgumentListEnd, ArgumentListEnd>>::push_arg`
 
-error[E0599]: the method `fire` exists for struct `ink_env::call::CallBuilder<DefaultEnvironment, Set<ink_env::AccountId>, Unset<u64>, Unset<u128>, Set<ExecutionInput<ArgumentList<ink_env::call::utils::Argument<NonCodecType>, ArgumentList<ArgumentListEnd, ArgumentListEnd>>>>, Set<()>>`, but its trait bounds were not satisfied
+error[E0599]: the method `fire` exists for struct `ink_env::call::CallBuilder<DefaultEnvironment, Set<ink_env::AccountId>, Unset<u64>, Unset<u128>, Set<ExecutionInput<ArgumentList<ink_env::call::utils::Argument<NonCodecType>, ArgumentList<ArgumentListEnd, ArgumentListEnd>>>>, Set<ReturnType<()>>>`, but its trait bounds were not satisfied
   --> tests/ui/contract/fail/message-input-non-codec.rs:18:9
    |
 18 |         pub fn message(&self, _input: NonCodecType) {}
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ method cannot be called on `ink_env::call::CallBuilder<DefaultEnvironment, Set<ink_env::AccountId>, Unset<u64>, Unset<u128>, Set<ExecutionInput<ArgumentList<ink_env::call::utils::Argument<NonCodecType>, ArgumentList<ArgumentListEnd, ArgumentListEnd>>>>, Set<()>>` due to unsatisfied trait bounds
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ method cannot be called on `ink_env::call::CallBuilder<DefaultEnvironment, Set<ink_env::AccountId>, Unset<u64>, Unset<u128>, Set<ExecutionInput<ArgumentList<ink_env::call::utils::Argument<NonCodecType>, ArgumentList<ArgumentListEnd, ArgumentListEnd>>>>, Set<ReturnType<()>>>` due to unsatisfied trait bounds
    |
   ::: $WORKSPACE/crates/env/src/call/execution_input.rs
    |
diff --git a/crates/lang/tests/ui/trait_def/fail/message_input_non_codec.stderr b/crates/lang/tests/ui/trait_def/fail/message_input_non_codec.stderr
index 2b0fe21ef79..75e38274408 100644
--- a/crates/lang/tests/ui/trait_def/fail/message_input_non_codec.stderr
+++ b/crates/lang/tests/ui/trait_def/fail/message_input_non_codec.stderr
@@ -25,12 +25,12 @@ note: required by a bound in `ExecutionInput::<ArgumentList<ArgumentListEnd, Arg
    |         T: scale::Encode,
    |            ^^^^^^^^^^^^^ required by this bound in `ExecutionInput::<ArgumentList<ArgumentListEnd, ArgumentListEnd>>::push_arg`
 
-error[E0599]: the method `fire` exists for struct `CallBuilder<E, Set<<E as Environment>::AccountId>, Unset<u64>, Unset<<E as Environment>::Balance>, Set<ExecutionInput<ArgumentList<ink_env::call::utils::Argument<NonCodec>, ArgumentList<ArgumentListEnd, ArgumentListEnd>>>>, Set<()>>`, but its trait bounds were not satisfied
+error[E0599]: the method `fire` exists for struct `CallBuilder<E, Set<<E as Environment>::AccountId>, Unset<u64>, Unset<<E as Environment>::Balance>, Set<ExecutionInput<ArgumentList<ink_env::call::utils::Argument<NonCodec>, ArgumentList<ArgumentListEnd, ArgumentListEnd>>>>, Set<ReturnType<()>>>`, but its trait bounds were not satisfied
   --> tests/ui/trait_def/fail/message_input_non_codec.rs:7:5
    |
 7  | /     #[ink(message)]
 8  | |     fn message(&self, input: NonCodec);
-   | |_______________________________________^ method cannot be called on `CallBuilder<E, Set<<E as Environment>::AccountId>, Unset<u64>, Unset<<E as Environment>::Balance>, Set<ExecutionInput<ArgumentList<ink_env::call::utils::Argument<NonCodec>, ArgumentList<ArgumentListEnd, ArgumentListEnd>>>>, Set<()>>` due to unsatisfied trait bounds
+   | |_______________________________________^ method cannot be called on `CallBuilder<E, Set<<E as Environment>::AccountId>, Unset<u64>, Unset<<E as Environment>::Balance>, Set<ExecutionInput<ArgumentList<ink_env::call::utils::Argument<NonCodec>, ArgumentList<ArgumentListEnd, ArgumentListEnd>>>>, Set<ReturnType<()>>>` due to unsatisfied trait bounds
    |
   ::: $WORKSPACE/crates/env/src/call/execution_input.rs
    |
diff --git a/examples/erc1155/lib.rs b/examples/erc1155/lib.rs
index 60a643eb32f..7060f57e9e5 100644
--- a/examples/erc1155/lib.rs
+++ b/examples/erc1155/lib.rs
@@ -381,13 +381,12 @@ mod erc1155 {
             value: Balance,
             data: Vec<u8>,
         ) {
-            // This is disabled during tests due to the use of `eval_contract()` not being
+            // This is disabled during tests due to the use of `invoke_contract()` not being
             // supported (tests end up panicking).
             #[cfg(not(test))]
             {
                 use ink_env::call::{
                     build_call,
-                    utils::ReturnType,
                     ExecutionInput,
                     Selector,
                 };
@@ -405,10 +404,10 @@ mod erc1155 {
                             .push_arg(value)
                             .push_arg(data),
                     )
-                    .returns::<ReturnType<Vec<u8>>>()
+                    .returns::<Vec<u8>>()
                     .params();
 
-                match ink_env::eval_contract(&params) {
+                match ink_env::invoke_contract(&params) {
                     Ok(v) => {
                         ink_env::debug_println!(
                             "Received return value \"{:?}\" from contract {:?}",
diff --git a/examples/multisig/lib.rs b/examples/multisig/lib.rs
index 365834cc30c..e6e643e8d9b 100755
--- a/examples/multisig/lib.rs
+++ b/examples/multisig/lib.rs
@@ -66,7 +66,6 @@ use ink_lang as ink;
 mod multisig {
     use ink_env::call::{
         build_call,
-        utils::ReturnType,
         ExecutionInput,
     };
     use ink_prelude::vec::Vec;
@@ -551,7 +550,7 @@ mod multisig {
                 .exec_input(
                     ExecutionInput::new(t.selector.into()).push_arg(CallInput(&t.input)),
                 )
-                .returns::<ReturnType<Vec<u8>>>()
+                .returns::<Vec<u8>>()
                 .fire()
                 .map_err(|_| Error::TransactionFailed);
             self.env().emit_event(Execution {