diff --git a/tools/src/caserun-native-service.ts b/tools/src/caserun-native-service.ts
index 25a01248..8cbff8b7 100644
--- a/tools/src/caserun-native-service.ts
+++ b/tools/src/caserun-native-service.ts
@@ -106,8 +106,7 @@ async function releaseStaleServicePort(service: ServiceName, env: Record<string,
   const port = Number(requiredEnv(env, service === "worker" ? "CASERUN_WORKER_HEALTH_PORT" : `${prefix}_PORT`));
   if (await portAvailable(bindHost, port)) return;
   const expectedPortKey = service === "api" ? "HARNESSRL_API_PORT" : service === "worker" ? "HARNESSRL_WORKER_HEALTH_PORT" : "WORKBENCH_WEB_PORT";
-  const commandMarker = service === "api" ? "hwlab-harnessrl-api/main.ts" : service === "worker" ? "hwlab-harnessrl-worker/main.ts" : "dev:native-caserun";
-  const candidates = await matchingServiceGroups(commandMarker, expectedPortKey, String(port));
+  const candidates = await matchingServiceGroups(expectedPortKey, String(port));
   if (candidates.length === 0) {
     throw codedError("native_port_owned_by_other_service", `CaseRun ${service} port ${port} is occupied by another service`);
   }
@@ -125,17 +124,15 @@ async function releaseStaleServicePort(service: ServiceName, env: Record<string,
   if (!await waitForPort(bindHost, port, 1_000)) throw codedError("native_port_release_timeout", `CaseRun ${service} port ${port} did not become available`);
 }
 
-async function matchingServiceGroups(commandMarker: string, portKey: string, port: string): Promise<number[]> {
+async function matchingServiceGroups(portKey: string, port: string): Promise<number[]> {
   const groups = new Set<number>();
   for (const entry of await readdir("/proc").catch(() => [])) {
     if (!/^\d+$/u.test(entry)) continue;
     const base = `/proc/${entry}`;
-    const [cmdline, environ, stat] = await Promise.all([
-      readFile(`${base}/cmdline`, "utf8").catch(() => ""),
+    const [environ, stat] = await Promise.all([
       readFile(`${base}/environ`, "utf8").catch(() => ""),
       readFile(`${base}/stat`, "utf8").catch(() => ""),
     ]);
-    if (!cmdline.replace(/\0/gu, " ").includes(commandMarker)) continue;
     const variables = environ.split("\0");
     if (!variables.includes("HWLAB_CASERUN_NATIVE_TEST=1") || !variables.includes(`${portKey}=${port}`)) continue;
     const fields = stat.slice(stat.lastIndexOf(") ") + 2).trim().split(/\s+/u);