When deploying paperless-ng stack with docker-compose file in Portainer you can’t login to paperless admin because superuser for login is missing (not created). You need to create it by going into container webserver CLI console and create it. Check screenshots for details.

python3 manage.py createsuperuser

For reference, this is my docker-compose.yml file with some additional services (Tika and Gotenberg – used for parsing and converting Office documents):

version: "3.4"
services:
  broker:
    image: redis:6.0
    restart: unless-stopped

  db:
    image: postgres:13
    restart: unless-stopped
    volumes:
      - pgdata:/var/lib/postgresql/data
    environment:
      POSTGRES_DB: paperless
      POSTGRES_USER: paperless
      POSTGRES_PASSWORD: paperless

  webserver:
    image: jonaswinkler/paperless-ng:latest
    restart: unless-stopped
    depends_on:
      - db
      - broker
      - gotenberg
      - tika
    ports:
      - 8010:8000
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:8000"]
      interval: 30s
      timeout: 10s
      retries: 5
    volumes:
      - data:/usr/src/paperless/data
      - media:/usr/src/paperless/media
      - ./export:/usr/src/paperless/export
      - ./consume:/usr/src/paperless/consume
    environment:
      PAPERLESS_REDIS: redis://broker:6379
      PAPERLESS_DBHOST: db
      PAPERLESS_TIKA_ENABLED: 1
      PAPERLESS_TIKA_GOTENBERG_ENDPOINT: http://gotenberg:3000
      PAPERLESS_TIKA_ENDPOINT: http://tika:9998
      PAPERLESS_TIME_ZONE: Europe/Ljubljana
      PAPERLESS_OCR_LANGUAGES: slv
      # consumption directory.
      USERMAP_UID: 1000
      USERMAP_GID: 100

  gotenberg:
    image: thecodingmachine/gotenberg
    restart: unless-stopped
    environment:
      DISABLE_GOOGLE_CHROME: 1

  tika:
    image: apache/tika
    restart: unless-stopped

volumes:
  data:
  media:
  pgdata: