diff --git a/vitest.config.mts b/vitest.config.mts
index 357a96c8..a0c8e476 100644
--- a/vitest.config.mts
+++ b/vitest.config.mts
@@ -18,5 +18,8 @@ export default defineConfig({
     include: ["**/*.test.ts"],
     exclude: ["**/node_modules/**", "**/build/**"],
     globals: true,
+    // Mirrors the `test:unit` npm script so tests run with NODE_ENV=unit no matter how they're launched (CLI, IDE/Vitest extension). Code under test (e.g. ssh.ts) skips process-exiting side effects when NODE_ENV === "unit".
+    // TODO we should fix the unit tests to not set NODE_ENV and when we do we can remove this
+    env: { NODE_ENV: "unit" },
   },
 });