How can you stream responses from a route handler?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of Next.js conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
Use the Web Streams API (ReadableStream) in a route handler to stream data progressively to the client. This is useful for large payloads or server-sent updates.
export async function GET() {
const stream = new ReadableStream({
start(controller) {
controller.enqueue(new TextEncoder().encode("chunk1"));
controller.enqueue(new TextEncoder().encode("chunk2"));
controller.close();
},
});
return new Response(stream, {
headers: { "Content-Type": "text/plain" },
});
}
Candidate Response Strategy & Interview Tips
- Start with a concise one-sentence summary: Deliver a direct, confident answer first before expanding into nuances.
- Demonstrate real-world trade-offs: Discuss where this approach excels and when you would avoid it in production systems.
- Discuss complexity & edge cases: Proactively explain time/space complexity or boundary conditions (null values, scale limits).
- Prepare for interviewer follow-ups: Technical hiring panels frequently probe deeper into concurrency, backward compatibility, or alternative libraries.