diff --git a/Cargo.lock b/Cargo.lock
index 67aa6d3..d079217 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -414,7 +414,7 @@ dependencies = [
 
 [[package]]
 name = "sccmod"
-version = "0.6.2"
+version = "0.6.3"
 dependencies = [
  "anstyle",
  "clap",
diff --git a/Cargo.toml b/Cargo.toml
index 2179dbc..340037f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "sccmod"
 authors = ["Toby Davis \"Pencilcaseman\""]
-version = "0.6.2"
+version = "0.6.3"
 edition = "2021"
 readme = "README.md"
 license = "MIT OR Apache-2.0"
diff --git a/src/builders/cmake.rs b/src/builders/cmake.rs
index a5648f4..33474fe 100644
--- a/src/builders/cmake.rs
+++ b/src/builders/cmake.rs
@@ -18,7 +18,7 @@ pub enum CMakeBuildType {
 #[derive(Debug, Clone)]
 pub struct CMake {
     pub build_type: CMakeBuildType,
-    pub jobs: usize,
+    pub jobs: Option<usize>,
     pub prefix_args: Option<Vec<String>>,
     pub configure_flags: Option<Vec<String>>,
     pub cmake_root: Option<String>,
@@ -101,8 +101,13 @@ impl CMake {
         }
 
         shell.add_command(&format!(
-            "cmake --build . --config {:?} --parallel {:?}",
-            self.build_type, self.jobs
+            "cmake --build . --config {:?} --parallel {}",
+            self.build_type,
+            if let Some(jobs) = &self.jobs {
+                format!("{jobs}")
+            } else {
+                "".to_string()
+            }
         ));
 
         let (result, stdout, stderr) = shell.exec();
@@ -142,11 +147,20 @@ impl BuilderImpl for CMake {
             other => log::error(&format!("Unknown CMake build type {other}")),
         };
 
-        let jobs: usize = object
+        // let jobs: usize = object
+        //     .getattr("jobs")
+        //     .map_err(|_| "Failed to read attribute 'jobs' of Builder
+        // object")?     .extract()
+        //     .map_err(|_| "Failed to convert attribute 'jobs' to Rust
+        // usize")?;
+
+        let jobs: Option<usize> = object
             .getattr("jobs")
             .map_err(|_| "Failed to read attribute 'jobs' of Builder object")?
             .extract()
-            .map_err(|_| "Failed to convert attribute 'jobs' to Rust usize")?;
+            .map_err(|_| {
+                "Failed to convert attribute 'jobs' to Rust Option<usize>"
+            })?;
 
         let prefix_args: Option<Vec<String>> = object
             .getattr("prefix_args")
diff --git a/src/builders/make.rs b/src/builders/make.rs
index c1a6f71..1a03506 100644
--- a/src/builders/make.rs
+++ b/src/builders/make.rs
@@ -10,7 +10,7 @@ use crate::{
 #[derive(Debug, Clone)]
 pub struct Make {
     pub configure: bool,
-    pub jobs: usize,
+    pub jobs: Option<usize>,
     pub prefix_args: Option<Vec<String>>,
     pub configure_flags: Option<Vec<String>>,
     pub make_root: Option<String>,
@@ -50,8 +50,6 @@ impl Make {
             shell.add_command(&format!("module load {dep}"));
         }
 
-        // let mut configure_cmd = format!("{source_path:?}/configure");
-
         // Apply prefix args
         let mut configure_cmd = String::new();
         if let Some(args) = &self.prefix_args {
@@ -101,7 +99,15 @@ impl Make {
         }
 
         shell.set_current_dir(&path.as_ref().to_str().unwrap());
-        shell.add_command(&format!("make -j {}", self.jobs));
+
+        shell.add_command(&format!(
+            "make -j {}",
+            if let Some(jobs) = &self.jobs {
+                format!("{jobs}")
+            } else {
+                "".to_string()
+            }
+        ));
 
         let (result, stdout, stderr) = shell.exec();
         let result = result.map_err(|_| "Failed to run make")?;
@@ -130,11 +136,20 @@ impl BuilderImpl for Make {
                 "Failed to convert attribute 'configure' to Rust bool"
             })?;
 
-        let jobs: usize = object
+        // let jobs: usize = object
+        //     .getattr("jobs")
+        //     .map_err(|_| "Failed to read attribute 'jobs' of Builder
+        // object")?     .extract()
+        //     .map_err(|_| "Failed to convert attribute 'jobs' to Rust
+        // usize")?;
+
+        let jobs: Option<usize> = object
             .getattr("jobs")
             .map_err(|_| "Failed to read attribute 'jobs' of Builder object")?
             .extract()
-            .map_err(|_| "Failed to convert attribute 'jobs' to Rust usize")?;
+            .map_err(|_| {
+                "Failed to convert attribute 'jobs' to Rust Option<usize>"
+            })?;
 
         let prefix_args: Option<Vec<String>> = object
             .getattr("prefix_args")