diff --git a/services/api/src/config.ts b/services/api/src/config.ts
index 2f4dbf1..acf9c47 100644
--- a/services/api/src/config.ts
+++ b/services/api/src/config.ts
@@ -23,6 +23,14 @@ const OptionalGithubOrganization = z.preprocess(
     .optional(),
 );
 
+// .env templates ship optional keys as blank assignments (KEY=), which dotenv
+// delivers as empty strings — those must parse as unset, while a value that is
+// actually set must still be non-empty.
+const OptionalNonEmpty = z.preprocess(
+  (value) => (typeof value === "string" && value.trim() === "" ? undefined : value),
+  z.string().trim().min(1).optional(),
+);
+
 const EnvSchema = z
   .object({
     DATABASE_URL: z.string().url(),
@@ -69,13 +77,13 @@ const EnvSchema = z
     S3_SECRET_KEY: z.string().optional(),
     S3_BUCKET: z.string().optional(),
     AWS_REGION: z.string().optional(),
-    FACILITY_AWS_CODEBUILD_PROJECT: z.string().trim().min(1).optional(),
-    FACILITY_AWS_CODEBUILD_CACHE_BASE_LOCATION: z.string().trim().min(1).optional(),
-    VERCEL_TOKEN: z.string().trim().min(1).optional(),
-    VERCEL_OIDC_TOKEN: z.string().trim().min(1).optional(),
-    VERCEL_TEAM_ID: z.string().trim().min(1).optional(),
-    VERCEL_PROJECT_ID: z.string().trim().min(1).optional(),
-    PACKAGE_REGISTRY_TOKEN: z.string().trim().min(1).optional(),
+    FACILITY_AWS_CODEBUILD_PROJECT: OptionalNonEmpty,
+    FACILITY_AWS_CODEBUILD_CACHE_BASE_LOCATION: OptionalNonEmpty,
+    VERCEL_TOKEN: OptionalNonEmpty,
+    VERCEL_OIDC_TOKEN: OptionalNonEmpty,
+    VERCEL_TEAM_ID: OptionalNonEmpty,
+    VERCEL_PROJECT_ID: OptionalNonEmpty,
+    PACKAGE_REGISTRY_TOKEN: OptionalNonEmpty,
     GITHUB_APP_ID: z.string().optional(),
     GITHUB_APP_PRIVATE_KEY: z.string().optional(),
     GITHUB_APP_WEBHOOK_SECRET: z.string().optional(),
diff --git a/services/api/test/config.test.ts b/services/api/test/config.test.ts
index 890af7a..50339d3 100644
--- a/services/api/test/config.test.ts
+++ b/services/api/test/config.test.ts
@@ -193,6 +193,34 @@ describe("API configuration", () => {
     });
   });
 
+  it("boots when .env-template blanks leave optional non-empty vars empty", () => {
+    // .env.example ships these as `KEY=`, which dotenv delivers as empty
+    // strings — a fresh `pnpm dev` copies them verbatim, so blank must mean
+    // unset or the first boot crashes.
+    const config = readConfig({
+      ...validEnv,
+      VERCEL_TOKEN: "",
+      VERCEL_OIDC_TOKEN: "",
+      VERCEL_TEAM_ID: "",
+      VERCEL_PROJECT_ID: "",
+      PACKAGE_REGISTRY_TOKEN: "",
+      FACILITY_AWS_CODEBUILD_PROJECT: "",
+      FACILITY_AWS_CODEBUILD_CACHE_BASE_LOCATION: "",
+    });
+    expect(config.vercelToken).toBeUndefined();
+    expect(config.vercelTeamId).toBeUndefined();
+    expect(config.vercelProjectId).toBeUndefined();
+    expect(config.packageRegistryToken).toBeUndefined();
+    expect(config.awsCodeBuildProject).toBeUndefined();
+    expect(config.awsCodeBuildCacheBaseLocation).toBeUndefined();
+  });
+
+  it("treats whitespace-only optional non-empty vars as unset, matching absence", () => {
+    expect(readConfig({ ...validEnv, VERCEL_TOKEN: "   " }).vercelToken).toBe(
+      readConfig(validEnv).vercelToken,
+    );
+  });
+
   it("rejects the direct GitHub organization restriction in broker mode", () => {
     expect(() =>
       readConfig({