docker-compose setup doesn't allow container to connect to redis

Question

So I'm writing a node application, and my docker-compose.yml looks like:

version: '2'
services:
  redis:
    image: "redis:latest"
  web:
    build: .
    ports:
     - "3000:3000"
    volumes:
     - .:/app
    links:
     - redis
  emailworker:
    build: .
    env_file:
      - ./.env
    command: node ./lib/workers/email.js
    volumes:
      - .:/app
    links:
      - redis
  smsworker:
    build: .
    env_file:
      - ./.env
    command: node ./lib/workers/sms.js
    volumes:
      - .:/app
    links:
      - redis

Pretty straight forward, a webserver, and two workers to process email and sms jobs. All has been great, until this afternoon, where nothing seemed to change, but I can not longer connect to the redis container when my app boots up. I run docker-compose up and I get the following error when trying to connect to redis using the kue node module:

Error: Redis connection to 127.0.0.1:6379 failed - connect ECONNREFUSED 127.0.0.1:6379
at Object.exports._errnoException (util.js:1022:11)
at exports._exceptionWithHostPort (util.js:1045:20)
at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1087:14)

My kue connection to redis looks like:

const kue = require('kue'),
  queue = kue.createQueue({
    root: __dirname,
    redis: {
      host: 'redis',
      port: 6379
    }
  });

queue.on('error', err => {
  console.log('QUEUE ERROR: ', err);
});

Any ideas where I'm going wrong here? I just set this up last night and emails were happily being sent, and like I mentioned, the only thing that would have changed is app code in the web service. I'm developing on a Mac if that makes a difference and have the latest version of docker and docker-compose. A docker ps after doing a docker-compose up shows:

CONTAINER ID        IMAGE                COMMAND                  CREATED              STATUS              PORTS                    NAMES
3af92333ad53        expapi_web           "yarn docker"            About a minute ago   Up About a minute   0.0.0.0:3000->3000/tcp   expapi_web_1
d26f1d81ad22        expapi_emailworker   "node ./lib/workers/e"   About a minute ago   Up About a minute   3000/tcp                 expapi_emailworker_1
1695ec819777        expapi_smsworker     "node ./lib/workers/s"   About a minute ago   Up About a minute   3000/tcp                 expapi_smsworker_1
5cb6701f3586        redis:latest         "docker-entrypoint.sh"   About a minute ago   Up About a minute   6379/tcp                 expapi_redis_1