diff --git a/src/repo/hooks.rs b/src/repo/hooks.rs
index 83e2e06..7567874 100644
--- a/src/repo/hooks.rs
+++ b/src/repo/hooks.rs
@@ -1,5 +1,6 @@
 use embed_nu::{CommandGroupConfig, Context};
 use rusty_value::*;
+use serde::Serialize;
 use std::{
     fs, mem,
     path::{Path, PathBuf},
@@ -23,13 +24,13 @@ impl std::fmt::Debug for HookScript {
     }
 }
 
-#[derive(Clone, Debug, RustyValue)]
+#[derive(Clone, Debug, RustyValue, Serialize)]
 pub struct ApplyAllContext {
     pub repo: PathBuf,
     pub paths: Vec<PathBuf>,
 }
 
-#[derive(Clone, Debug, RustyValue)]
+#[derive(Clone, Debug, RustyValue, Serialize)]
 pub struct ApplyEachContext {
     pub repo: PathBuf,
     pub src: PathBuf,
diff --git a/src/scripting/utils_module.rs b/src/scripting/utils_module.rs
index 4c04a1a..e9b42ef 100644
--- a/src/scripting/utils_module.rs
+++ b/src/scripting/utils_module.rs
@@ -1,16 +1,46 @@
-use std::fs;
+use std::{
+    fs,
+    process::{Command, Stdio},
+};
 
-use mlua::{Lua, LuaSerdeExt, Result, Table};
+use mlua::{Function, Lua, LuaSerdeExt, Result, Table};
+use serde::Serialize;
 
+/// Utility functions
 pub fn utils_module(lua: &Lua) -> Result<Table> {
     let exports = lua.create_table()?;
 
     exports.set("merge", lua.create_function(lua_merge)?)?;
-    exports.set("load_toml", lua.create_function(lua_read_toml)?)?;
+    exports.set("from_json", lua.create_function(lua_from_json)?)?;
+    exports.set("load_json", lua.create_function(lua_load_json)?)?;
+    exports.set("from_toml", lua.create_function(lua_from_toml)?)?;
+    exports.set("load_toml", lua.create_function(lua_load_toml)?)?;
+    exports.set("ext", lua.create_function(lua_ext)?)?;
+    exports.set("ext_piped", lua.create_function(lua_ext_piped)?)?;
+
+    if let Ok(nu_path) = which::which("nu") {
+        exports.set(
+            "nu",
+            lua.create_function(move |lua, expr| {
+                let output = Command::new(&nu_path)
+                    .arg("-c")
+                    .arg::<String>(expr)
+                    .stdout(Stdio::piped())
+                    .spawn()?
+                    .wait_with_output()?;
+
+                let output_string =
+                    String::from_utf8(output.stdout).map_err(mlua::Error::external)?;
+
+                lua.to_value(&output_string)
+            })?,
+        )?;
+    }
 
     Ok(exports)
 }
 
+/// Merges two values
 fn lua_merge<'a>(lua: &'a Lua, (a, b): (mlua::Value, mlua::Value)) -> Result<mlua::Value<'a>> {
     let val_a: serde_json::Value = lua.from_value(a)?;
     let val_b: serde_json::Value = lua.from_value(b)?;
@@ -19,9 +49,74 @@ fn lua_merge<'a>(lua: &'a Lua, (a, b): (mlua::Value, mlua::Value)) -> Result<mlu
     lua.to_value(&merged)
 }
 
-fn lua_read_toml<'a>(lua: &'a Lua, path: String) -> Result<mlua::Value<'a>> {
+/// Parse a json string into a lua value
+fn lua_from_json<'a>(lua: &'a Lua, json_string: String) -> Result<mlua::Value<'a>> {
+    let toml_value: serde_json::Value =
+        serde_json::from_str(&json_string).map_err(mlua::Error::external)?;
+
+    lua.to_value(&toml_value)
+}
+
+/// Reads a json file and parses it as a lua value
+fn lua_load_json<'a>(lua: &'a Lua, path: String) -> Result<mlua::Value<'a>> {
     let contents = fs::read_to_string(path)?;
-    let toml_value: toml::Value = toml::from_str(&contents).map_err(mlua::Error::external)?;
+    lua_from_json(lua, contents)
+}
+
+/// Parse a toml string into a lua value
+fn lua_from_toml<'a>(lua: &'a Lua, toml_string: String) -> Result<mlua::Value<'a>> {
+    let toml_value: toml::Value = toml::from_str(&toml_string).map_err(mlua::Error::external)?;
 
     lua.to_value(&toml_value)
 }
+
+/// Reads a toml file and parses it as a lua value
+fn lua_load_toml<'a>(lua: &'a Lua, path: String) -> Result<mlua::Value<'a>> {
+    let contents = fs::read_to_string(path)?;
+    lua_from_toml(lua, contents)
+}
+
+/// Creates a new executable that can be called with a variable number of args
+fn lua_ext<'a>(lua: &'a Lua, program: String) -> Result<Function<'a>> {
+    lua.create_function(move |_lua, args| {
+        let exit_status = Command::new(&program)
+            .args::<Vec<String>, _>(args)
+            .stdout(Stdio::inherit())
+            .stderr(Stdio::inherit())
+            .spawn()?
+            .wait()?;
+        if exit_status.success() {
+            Ok(())
+        } else {
+            Err(mlua::Error::external(format!(
+                "External command `{program}` failed"
+            )))
+        }
+    })
+}
+
+#[derive(Serialize)]
+struct CommandOutput {
+    code: i32,
+    stdout: String,
+    stderr: String,
+}
+
+/// Creates a new executable that can be called with a variable number of args
+fn lua_ext_piped<'a>(lua: &'a Lua, program: String) -> Result<Function<'a>> {
+    lua.create_function(move |lua, args| {
+        let cmd = Command::new(&program)
+            .args::<Vec<String>, _>(args)
+            .stdout(Stdio::piped())
+            .stderr(Stdio::piped())
+            .spawn()?;
+        let output = cmd.wait_with_output()?;
+        let output = CommandOutput {
+            code: output.status.code().unwrap_or(0),
+            stdout: String::from_utf8(output.stdout).map_err(mlua::Error::external)?,
+            stderr: String::from_utf8(output.stderr).map_err(mlua::Error::external)?,
+        };
+
+        lua.to_value(&output)
+    })
+}