AdonisJS v7 Transmit Setup (you must uninstall the official package then register the custom provider and preload file).

transmit.ts

import type { HttpContext } from '@adonisjs/core/http'
import app from '@adonisjs/core/services/app'
import router from '@adonisjs/core/services/router'
import { RuntimeException } from '@poppinss/utils/exception'

const transmit = await app.container.make('transmit')

transmit.authorize<{ id: string }>('users/:id', async (ctx: HttpContext, params) => {
  const userId = ctx.auth.user?.id

  if (!userId) {
    return false
  }

  return userId === params.id
})

router.get('/__transmit/events', async (ctx) => {
  const uid = ctx.request.input('uid')

  if (!uid) {
    throw new RuntimeException('Missing required field "uid" in the request body')
  }

  const stream = transmit.createStream({
    uid,
    context: ctx,
    request: ctx.request.request,
    response: ctx.response.response,
    injectResponseHeaders: ctx.response.getHeaders(),
  })

  return ctx.response.stream(stream)
})

router.post('/__transmit/subscribe', async (ctx) => {
  const uid = ctx.request.input('uid')

  const channel = ctx.request.input('channel')

  const success = await transmit.subscribe({
    uid,
    channel,
    context: ctx,
  })

  if (!success) {
    return ctx.response.badRequest()
  }

  return ctx.response.noContent()
})

router.post('/__transmit/unsubscribe', async (ctx) => {
  const uid = ctx.request.input('uid')

  const channel = ctx.request.input('channel')

  const success = await transmit.unsubscribe({
    uid,
    channel,
    context: ctx,
  })

  if (!success) {
    return ctx.response.badRequest()
  }

  return ctx.response.noContent()
})

transmit_provider.ts

import type { ApplicationService } from '@adonisjs/core/types'
import type { HttpContext } from '@adonisjs/core/http'
import { Transmit } from '@boringnode/transmit'
import { TransmitConfig } from '@boringnode/transmit/types'

declare module '@adonisjs/core/types' {
  interface ContainerBindings {
    'transmit': Transmit<HttpContext>
  }
}

export default class TransmitProvider {
  constructor(protected app: ApplicationService) {}

  /**
   * Register bindings to the container
   */
  register() {
    this.app.container.singleton('transmit', async () => {
      const config = this.app.config.get<TransmitConfig>('transmit', {})

      let transport: Transport | null = null

      if (config.transport) {
        transport = config.transport.driver()
      }

      return new Transmit(config, transport)
    })
  }

  /**
   * The container bindings have booted
   */
  async boot() {
    //
  }

  /**
   * The application has been booted
   */
  async start() {
    //
  }

  /**
   * The process has been started
   */
  async ready() {
    //
  }

  /**
   * Preparing to shut down the app
   */
  async shutdown() {
    const transmit = await this.app.container.make('transmit')

    await transmit.shutdown()
  }
}