Promise pipeline with context object...

pipeline.js

const { assign } = Object

const mergeResults = (pipeline, step) => (
  pipeline.then((context) => (
    step(context).then((result) => (
      assign({}, context, result)
    ))
  ))
)

const createPipeline = (...steps) => (context) => (
  steps.reduce(mergeResults, Promise.resolve(context))
)

const pipeline = createPipeline(
  ({ start }) => Promise.resolve({ upper: start.toUpperCase() }),
  ({ upper }) => Promise.resolve({ reverse: upper.split('').reverse().join('') })
)

pipeline({ start: 'Hey there' }).then((result) => console.log(result))

// Logs:
// { start: 'Hey there', upper: 'HEY THERE', reverse: 'EREHT YEH' }