diff --git a/tests/steps/process_steps.rs b/tests/steps/process_steps.rs
index be67517a..7edbc961 100644
--- a/tests/steps/process_steps.rs
+++ b/tests/steps/process_steps.rs
@@ -5,7 +5,7 @@ use cucumber::{given, then, when};
 use netsuke::runner::{self, BuildTargets};
 use std::fs;
 use std::path::{Path, PathBuf};
-use tempfile::TempDir;
+use tempfile::{NamedTempFile, TempDir};
 
 /// Installs a test-specific ninja binary and updates the `PATH`.
 #[expect(
@@ -79,6 +79,29 @@ fn build_dir_exists(world: &mut CliWorld) {
 )]
 #[when("the ninja process is run")]
 fn run(world: &mut CliWorld) {
+    let dir = world.temp.as_ref().expect("temp dir");
+    let manifest_path = {
+        let cli = world.cli.as_ref().expect("cli");
+        if cli.file.is_absolute() {
+            cli.file.clone()
+        } else {
+            dir.path().join(&cli.file)
+        }
+    };
+
+    if !manifest_path.exists() {
+        let mut file =
+            NamedTempFile::new_in(dir.path()).expect("Failed to create temporary manifest file");
+        support::write_manifest(&mut file).expect("Failed to write manifest content");
+        file.persist(&manifest_path)
+            .expect("Failed to persist manifest file");
+    }
+
+    {
+        let cli = world.cli.as_mut().expect("cli");
+        cli.file.clone_from(&manifest_path);
+    }
+
     let cli = world.cli.as_ref().expect("cli");
     let program = if let Some(ninja) = &world.ninja {
         Path::new(ninja)
diff --git a/tests/support/mod.rs b/tests/support/mod.rs
index bd051cd2..caba6283 100644
--- a/tests/support/mod.rs
+++ b/tests/support/mod.rs
@@ -1,4 +1,7 @@
-//! Test utilities for process management and log capture.
+//! Test utilities for process management.
+//!
+//! This module provides helpers for creating fake executables and
+//! generating minimal manifests used in behavioural tests.
 
 use std::fs::{self, File};
 use std::io::{self, Write};
@@ -134,3 +137,23 @@ pub fn fake_ninja_pwd() -> (TempDir, PathBuf) {
     }
     (dir, path)
 }
+
+/// Write a minimal manifest to `file`.
+///
+/// The manifest declares a single `hello` target that prints a greeting.
+/// This must be `allow` as `expect` will trigger an unfulfilled warning
+/// despite the lint violation arising.
+#[allow(dead_code, reason = "shared test utility not used in all crates")]
+pub fn write_manifest(file: &mut impl Write) -> io::Result<()> {
+    writeln!(
+        file,
+        concat!(
+            "netsuke_version: \"1.0.0\"\n",
+            "targets:\n",
+            "  - name: hello\n",
+            "    recipe:\n",
+            "      kind: command\n",
+            "      command: \"echo hi\"\n"
+        ),
+    )
+}