Suddenly getting build failures after no changes to the config

I’m doing a basic update to my readme & getting a failure I’ve never received:

#!/bin/bash -eo pipefail
export NVM_DIR="/opt/circleci/.nvm"
[ -s “$NVM_DIR/nvm.sh” ] && . “$NVM_DIR/nvm.sh”
nvm install v8.11.3
nvm alias default v8.11.3

module.js:440
throw err;
^

Error: Cannot find module ‘are-we-there-yet’
at Function.Module._resolveFilename (module.js:438:15)
at Function.Module._load (module.js:386:25)
at Module.require (module.js:466:17)
at require (internal/module.js:20:19)
at Object. (/opt/circleci/.nvm/versions/node/v6.1.0/lib/node_modules/npm/node_modules/npmlog/log.js:2:16)
at Module._compile (module.js:541:32)
at Object.Module._extensions…js (module.js:550:10)
at Module.load (module.js:456:32)
at tryModuleLoad (module.js:415:12)
at Function.Module._load (module.js:407:3)
nvm is not compatible with the npm config “prefix” option: currently set to “”
Run nvm use --delete-prefix v6.1.0 --silent to unset it.

Exited with code exit status 11
CircleCI received exit code 11

=========================

Here’s what the config looks like where it’s failing:

version: 2
jobs:
  build:
    machine: true
    steps:
    - checkout
    - run:
        name: Install node@v8.11.3
        command: |
          export NVM_DIR="/opt/circleci/.nvm"
          [ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
          nvm install v8.11.3
          nvm alias default v8.11.3
    - run:
        name: Install package
        command: |
          cd ./gutenberg
          export NVM_DIR="/opt/circleci/.nvm"
          [ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
          npm version
          npm install webpack --save-dev
          npm install nyc
          npm run build
          rm -rf node_modules

I’ve tried to solve this a number of different ways, but to no avail. Any ideas on how to proceed would be super helpful. Thanks!