Glossary term
What is Backpressure? Meaning for developers
In System Design
Slowing producers when consumers can't keep up. Example: Rejecting non-urgent jobs when the queue is too long.
Learn it properly · System DesignLesson 18: Message Queues: A Gentle IntroductionPlacing an order shouldn't wait on the email provider — or fail because SMS is down. How message queues let you do the essential work now and everything else reliably a moment later, with acks, retries, dead-letter queues and back pressure.In Backend in Depth
A slow reader tells the sender to pause, so data does not pile up in memory. Node streams do this for you.
Learn it properly · Backend in DepthLesson 10: Node.js Performance Basics: Event Loop Blocking, Streams, WorkersWhy one heavy CPU job can stop every request, plus streams for large data and worker threads.In Full-Stack Questions
A slow reader telling a fast writer to wait, so memory does not fill up. Streams do this for you.
Learn it properly · Full-Stack QuestionsLesson 6: Node.js & Express Interview QuestionsEvent loop, streams, workers, Express 5, security, graceful shutdown and performance.In Node.js From Zero
The signal from a slow reader or writer telling a fast source to wait, shown when write() returns false.
Learn it properly · Node.js From ZeroLesson 3: Streams and BackpressureReadable, writable and transform streams, pipeline, backpressure shown with real memory numbers, and when streams beat reading whole files.In Networking for Developers
Slowing down a sender because the receiver cannot keep up.
Learn it properly · Networking for DevelopersLesson 7: WebSockets, Server-Sent Events and Real-Time NetworkingPolling versus long polling, WebSockets, SSE, scaling real-time connections, and a working example of each.