Function start

packages/computer/src/retry.test.ts:70–73

(controller)

                id: "command-1",
                events: new ReadableStream({
                  start(controller) {
                    controller.enqueue({ id: "command-1", seq: 1, name: "exit", value: 0 });
                    controller.close();
                  },
                }),
              };
            },