diff --git a/src/routing/error.rs b/src/routing/error.rs
new file mode 100644
index 0000000..7a2c94b
--- /dev/null
+++ b/src/routing/error.rs
@@ -0,0 +1,22 @@
+use axum::Json;
+use axum::response::{IntoResponse, Response};
+use serde::Serialize;
+
+#[derive(Serialize)]
+pub struct Error {
+    pub message: String,
+}
+
+impl Error {
+    pub fn new(message: impl Into<String>) -> Self {
+        Self {
+            message: message.into(),
+        }
+    }
+}
+
+impl IntoResponse for Error {
+    fn into_response(self) -> Response {
+        Json(self).into_response()
+    }
+}
diff --git a/src/routing/mod.rs b/src/routing/mod.rs
index 0a968e6..41f8a26 100644
--- a/src/routing/mod.rs
+++ b/src/routing/mod.rs
@@ -1,3 +1,5 @@
 pub(crate) mod simplify;
 pub(crate) mod table;
-pub(crate) mod index;
\ No newline at end of file
+pub(crate) mod index;
+mod response;
+mod error;
\ No newline at end of file
diff --git a/src/routing/response.rs b/src/routing/response.rs
new file mode 100644
index 0000000..fc08402
--- /dev/null
+++ b/src/routing/response.rs
@@ -0,0 +1,56 @@
+use axum::Json;
+use axum::response::{IntoResponse, Response};
+use serde::Serialize;
+use crate::expressions::expression::Expression;
+use crate::expressions::truth_table::TruthTable;
+
+#[derive(Serialize)]
+struct BaseResponse<T: Serialize> {
+    version: String,
+    #[serde(flatten)]
+    result: T,
+}
+
+impl<T: Serialize> BaseResponse<T> {
+    fn create(result: T) -> Response {
+        Self {
+            version: env!("CARGO_PKG_VERSION").to_string(),
+            result,
+        }.into_response()
+    }
+}
+
+impl<T: Serialize> IntoResponse for BaseResponse<T> {
+    fn into_response(self) -> Response {
+        Json(self).into_response()
+    }
+}
+
+#[derive(Serialize)]
+enum Law {
+    // TODO
+}
+
+#[derive(Serialize)]
+pub struct OrderOfOperation {
+    before: String,
+    after: String,
+    law: Law, // TODO
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct SimplifyResponse {
+    pub before: String,
+    pub after: String,
+    pub order_of_operations: Vec<OrderOfOperation>,
+    pub expression: Expression,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub truth_table: Option<TruthTable>,
+}
+
+impl IntoResponse for SimplifyResponse {
+    fn into_response(self) -> Response {
+        BaseResponse::create(self)
+    }
+}
\ No newline at end of file
diff --git a/src/routing/simplify.rs b/src/routing/simplify.rs
index 87b91f5..87f241c 100644
--- a/src/routing/simplify.rs
+++ b/src/routing/simplify.rs
@@ -1,13 +1,15 @@
-use axum::{Json, Router, routing::get};
+use axum::{Router, routing::get};
 use axum::extract::{Path, Query};
 use axum::http::StatusCode;
 use axum::response::{IntoResponse, Response};
-use serde::{Deserialize, Serialize};
+use serde::Deserialize;
 
 use crate::expressions::expression::Expression;
 use crate::expressions::simplify::Simplify;
 use crate::expressions::truth_table::{TruthTable, TruthTableOptions};
 use crate::language::{AcceptLanguage, Language};
+use crate::routing::error::Error;
+use crate::routing::response::SimplifyResponse;
 
 pub fn router() -> Router<()> {
     Router::new()
@@ -22,7 +24,7 @@ const fn default_true() -> bool {
     true
 }
 
-#[derive(Deserialize, Debug)]
+#[derive(Deserialize)]
 struct QueryOptions {
     #[serde(default)]
     lang: Language,
@@ -32,35 +34,6 @@ struct QueryOptions {
     case_sensitive: bool,
 }
 
-#[derive(Serialize)]
-enum Law {
-    // TODO
-}
-
-#[derive(Serialize)]
-struct OrderOfOperation {
-    before: String,
-    after: String,
-    law: Law, // TODO
-}
-
-#[derive(Serialize)]
-#[serde(rename_all = "camelCase")]
-struct SimplifyResponse {
-    version: String,  // TODO better versioning
-    before: String,
-    after: String,
-    order_of_operations: Vec<OrderOfOperation>,
-    expression: Expression,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    truth_table: Option<TruthTable>,
-}
-
-#[derive(Serialize)]
-struct Error {
-    message: String,
-}
-
 // TODO
 async fn simplify(Path(path): Path<String>, query: Query<QueryOptions>, accept_language: Option<AcceptLanguage>) -> Response {
     if let Ok(mut expression) = Expression::try_from(path.as_str()) {
@@ -68,16 +41,15 @@ async fn simplify(Path(path): Path<String>, query: Query<QueryOptions>, accept_l
         if query.simplify {
             expression = expression.simplify();
         }
-        Json(SimplifyResponse {
-            version: "2.0.0".to_string(),
+        SimplifyResponse {
             before,
             after: expression.to_string(),
             order_of_operations: vec![], // TODO
             expression,
             truth_table: None,
-        }).into_response()
+        }.into_response()
     } else {
-        (StatusCode::BAD_REQUEST, Json(Error { message: "Invalid expression".into() })).into_response()
+        (StatusCode::BAD_REQUEST, Error::new("Invalid expression")).into_response()
     }
 }
 
@@ -89,15 +61,14 @@ async fn simplify_and_table(Path(path): Path<String>, query: Query<QueryOptions>
         }
         // TODO options
         let truth_table = TruthTable::new(&expression, TruthTableOptions::default());
-        Json(SimplifyResponse {
-            version: "2.0.0".to_string(),
+        SimplifyResponse {
             before,
             after: expression.to_string(),
             order_of_operations: vec![], // TODO
             expression,
             truth_table: Some(truth_table),
-        }).into_response()
+        }.into_response()
     } else {
-        (StatusCode::BAD_REQUEST, Json(Error { message: "Invalid expression".into() })).into_response()
+        (StatusCode::BAD_REQUEST, Error::new("Invalid expression")).into_response()
     }
 }