This is a little node app that creates individual csv files for each tag in an exported Drip subscriber (people!) csv

drip_to_convertkit.js

const _ = require('lodash')
const fs = require('fs')
const csv = require('csv-parser')
const writer = require('fast-csv')

const csvFilePath = 'PATH_TO.csv'

const filesToBuild = {}

fs.createReadStream(csvFilePath)
  .pipe(csv())
  .on('data', function(row) {
    const filterFor = 'sent - ' // only looking for tags with a specific string
    row.tags = _.filter(row.tags.split(','), tag => tag.includes(filterFor))
    row.tags.forEach(tag => {
      const { tags, ...props } = row
      //each tag will get its own csv output, so add it to the hash
      filesToBuild[tag] = filesToBuild[tag] || []
      filesToBuild[tag].push({ ...props })
    })
  })
  .on('end', function() {
    _.keys(filesToBuild).forEach(key => {
      //go through all the filtered tags and write a csv file with the appropriate rows
      writer.writeToPath(`./${key}.csv`, filesToBuild[key], { headers: true }).on('finish', function() {
        console.log(`wrote ${key}.csv`)
      })
    })
  })

package.json

{
  "name": "parse_drip",
  "version": "1.0.0",
  "description": "",
  "main": "drip_to_convertkit.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "csv-parser": "^2.1.0",
    "fast-csv": "^2.4.1",
    "lodash": "^4.17.11"
  }
}