@Fdawgs Do you have time to helps me check the document changes?

Sorry @climba03003, missed this. Will take a look next week.

Did you evaluate res.destroy instead?

The only difference is whether or not emit an error from the request object. Can't recall any other differences

Not quite understand what you means.

I needed to refresh this

const { fastify } = require('fastify')
const app = fastify()

app.get('/destroy', async (request, reply) => {
  reply.hijack()
  reply.raw.destroy('hello world')
})

app.get('/end', async (request, reply) => {
  reply.hijack()
  reply.raw.end('hello world')
})

app.inject('/end', check)
  .then(() => app.inject('/destroy', check))

function check (err, res) {
  console.log(err)
  console.log(res?.statusCode)
  console.log(res?.payload)
}

.destory cannot and will not send any payload to the client. Instead, it close the socket immediately.
.end return a proper error message to the client and they can deal with it other than just wait for browser socket timeout.