diff --git a/src/executor.rs b/src/executor.rs
index 6c88403..6cbb152 100644
--- a/src/executor.rs
+++ b/src/executor.rs
@@ -6,6 +6,8 @@ use std::{
 
 use crate::{Algorithm, Maze, Pos};
 
+use self::builder::{new_builder, BuildableMazeState, ExecutorBuilder, Unprovided};
+
 /// A guess to pass to the current [`Executor`] at the end of every `progress` call.
 pub struct Guess(Vec<Pos>);
 
@@ -79,11 +81,14 @@ impl<'m> Context<'m> {
     }
 }
 
+mod builder;
+
 /// A structure holding a [`Maze`] and iteratively solving it with a provided [`Algorithm`].
 pub struct Executor<Algo>
 where
     Algo: Algorithm,
 {
+    delay: Duration,
     maze: Maze,
     algorithm: Algo,
 }
@@ -93,13 +98,32 @@ where
     A: Algorithm,
 {
     /// Constructor.
-    pub fn new(maze: Maze, algorithm: A) -> Self {
-        Self { maze, algorithm }
+    fn new(maze: Maze, algorithm: A, delay: Duration) -> Self {
+        Self {
+            maze,
+            algorithm,
+            delay,
+        }
+    }
+
+    pub fn build<'f, F, MS>(algorithm: A, builder: F) -> Self
+    where
+        MS: BuildableMazeState,
+        F: Fn(ExecutorBuilder<Unprovided>) -> ExecutorBuilder<MS>,
+    {
+        let operation = builder;
+        let mut builder = (operation)(new_builder());
+        let (maze, delay) = builder.build();
+        Self::new(maze, algorithm, delay)
     }
 
     /// Submit the maze to the [`Algorithm`] and iteratively progress through the maze driven by said algorithm.
     pub fn run(&mut self) {
-        let Self { maze, algorithm } = self;
+        let Self {
+            maze,
+            algorithm,
+            delay,
+        } = self;
         let mut insight = Insight::from_position(maze.start(), &maze);
         let mut tick = 0;
         let mut tried = HashSet::new();
@@ -116,7 +140,7 @@ where
 
             // draw
             Self::draw(maze, &tried, tick, &guess);
-            thread::sleep(Duration::from_millis(100));
+            thread::sleep(*delay);
             tick += 1;
 
             // check for next iteration
diff --git a/src/executor/builder.rs b/src/executor/builder.rs
new file mode 100644
index 0000000..a0d5d74
--- /dev/null
+++ b/src/executor/builder.rs
@@ -0,0 +1,57 @@
+use std::time::Duration;
+
+use crate::{labyrinth::generator::MazeGenerator, Maze};
+
+pub trait MazeState {}
+pub trait BuildableMazeState: MazeState {
+    fn get(self) -> Maze;
+}
+
+pub struct Unprovided;
+
+impl MazeState for Unprovided {}
+
+struct Provided {
+    maze: Maze,
+}
+
+impl MazeState for Provided {}
+impl BuildableMazeState for Provided {
+    fn get(self) -> Maze {
+        self.maze
+    }
+}
+
+struct Generated {
+    generator: Box<dyn MazeGenerator>,
+}
+
+impl MazeState for Generated {}
+impl BuildableMazeState for Generated {
+    fn get(mut self) -> Maze {
+        self.generator.generate()
+    }
+}
+
+pub struct ExecutorBuilder<MS>
+where
+    MS: MazeState,
+{
+    maze_state: MS,
+    delay: Duration,
+}
+
+pub fn new_builder() -> ExecutorBuilder<Unprovided> {
+    ExecutorBuilder {
+        maze_state: Unprovided,
+        delay: Duration::from_millis(100),
+    }
+}
+
+impl<MS: BuildableMazeState> ExecutorBuilder<MS> {
+    pub fn build(self) -> (Maze, Duration) {
+        let maze = self.maze_state.get();
+        let delay = self.delay;
+        (maze, delay)
+    }
+}
diff --git a/src/implementations.rs b/src/implementations.rs
index 1f5d035..54fbc40 100644
--- a/src/implementations.rs
+++ b/src/implementations.rs
@@ -15,8 +15,8 @@ fn depth_first() {
     use crate::{generate, Executor};
     let algorithm = DepthFirst::new();
     let maze = generate(20, 20);
-    let mut executor = Executor::new(maze, algorithm);
-    executor.run();
+    // let mut executor = Executor::new(maze, algorithm);
+    // executor.run();
 }
 
 #[test]
@@ -24,6 +24,6 @@ fn breath_first() {
     use crate::{generate, Executor};
     let algorithm = BreathFirst::new();
     let maze = generate(20, 20);
-    let mut executor = Executor::new(maze, algorithm);
-    executor.run();
+    // let mut executor = Executor::new(maze, algorithm);
+    // executor.run();
 }
diff --git a/src/labyrinth/generator.rs b/src/labyrinth/generator.rs
index f4bdfb5..81e76be 100644
--- a/src/labyrinth/generator.rs
+++ b/src/labyrinth/generator.rs
@@ -44,3 +44,7 @@ fn generation() {
     let text = maze.display(None);
     println!("{text}");
 }
+
+pub trait MazeGenerator {
+    fn generate(&mut self) -> Maze;
+}