diff --git a/Cargo.lock b/Cargo.lock
index e97cb16..123e4ca 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -66,6 +66,7 @@ dependencies = [
  "eval",
  "ir",
  "owo-colors",
+ "prowocessing",
  "ron",
  "serde",
  "serde_json",
diff --git a/crates/app/Cargo.toml b/crates/app/Cargo.toml
index 10182c2..d316efc 100644
--- a/crates/app/Cargo.toml
+++ b/crates/app/Cargo.toml
@@ -12,6 +12,7 @@ clap = { workspace = true, features = [ "derive", "env" ] }
 dirs = "5"
 eval = { path = "../eval" }
 ir = { path = "../ir" }
+prowocessing = { path = "../prowocessing"}
 owo-colors = "4"
 ron = "0.8"
 serde = { workspace = true, features = [ "derive" ] }
diff --git a/crates/app/src/main.rs b/crates/app/src/main.rs
index 7d7eff2..2caaa2f 100644
--- a/crates/app/src/main.rs
+++ b/crates/app/src/main.rs
@@ -2,6 +2,7 @@ use std::{fs, path::PathBuf};
 
 use clap::{Parser, Subcommand};
 use config::{CliConfigs, Config};
+use dev::DevCommands;
 use welcome_msg::print_startup_msg;
 
 mod config;
@@ -24,7 +25,10 @@ enum Commands {
         /// What file contains the pipeline to evaluate.
         source: PathBuf,
     },
-    Dev,
+    Dev {
+        #[command(subcommand)]
+        dev_command: DevCommands,
+    },
 }
 
 fn main() {
@@ -46,8 +50,34 @@ fn main() {
             machine.feed(ir);
             machine.eval_full();
         }
-        Commands::Dev => {
-            println!("Hello world!");
+        Commands::Dev { dev_command } => dev_command.run(),
+    }
+}
+
+mod dev {
+    use clap::Subcommand;
+    use prowocessing::experimental::enum_based::{Pipeline, PipelineBuilder};
+
+    #[derive(Subcommand)]
+    pub(crate) enum DevCommands {
+        Enums { test_str: String },
+    }
+
+    impl DevCommands {
+        pub fn run(self) {
+            match self {
+                DevCommands::Enums { test_str } => {
+                    let upr = PipelineBuilder::new()
+                        .insert(prowocessing::experimental::enum_based::Instruction::Uppercase)
+                        .build();
+                    let lwr = PipelineBuilder::new()
+                        .insert(prowocessing::experimental::enum_based::Instruction::Lowercase)
+                        .build();
+
+                    println!("Upr: {}", upr.run(test_str.clone()));
+                    println!("Lwr: {}", lwr.run(test_str.clone()));
+                }
+            }
         }
     }
 }
diff --git a/crates/prowocessing/src/lib.rs b/crates/prowocessing/src/lib.rs
index 8affe30..778d544 100644
--- a/crates/prowocessing/src/lib.rs
+++ b/crates/prowocessing/src/lib.rs
@@ -7,7 +7,7 @@ use experimental::enum_based::{Instruction, PipelineBuilder};
 
 /// just some experiments, to test whether the architecture i want is even possible (or how to do it). probably temporary.
 /// Gonna first try string processing...
-mod experimental {
+pub mod experimental {
     pub mod enum_based {
         pub enum Instruction {
             Uppercase,
@@ -41,6 +41,7 @@ mod experimental {
                 }
             }
 
+            #[must_use]
             pub fn insert(mut self, instr: Instruction) -> Self {
                 self.pipeline.push(instr);
                 self
@@ -66,6 +67,12 @@ mod experimental {
                 Pipeline { pipeline: res }
             }
         }
+
+        impl Default for PipelineBuilder {
+            fn default() -> Self {
+                Self::new()
+            }
+        }
     }
 }