How to fix failed to process "FROM ${BASE_IMAGE}": no build argument in Docker

The recommended fix is to provide a sensible default value for your ARG so the build works without requiring --build-arg:

Before (broken):

ARG BASE_IMAGE
FROM ${BASE_IMAGE}

After (fixed):

ARG BASE_IMAGE=ubuntu:22.04
FROM ${BASE_IMAGE}

This way, if no --build-arg BASE_IMAGE=... is provided, Docker uses the default value ubuntu:22.04. You can still override it at build time:

docker build --build-arg BASE_IMAGE=alpine:3.18 -t myapp .

If you intentionally want to require the build argument (no default), pass it with --build-arg:

docker build --build-arg BASE_IMAGE=python:3.11-slim -t myapp .

For multiple build arguments:

docker build \
  --build-arg BASE_IMAGE=node:20-alpine \
  --build-arg APP_VERSION=1.0.0 \
  -t myapp .

Important: Do not add spaces around the equals sign. Use KEY=value, not KEY = value.

The ARG instruction must appear BEFORE the FROM instruction to be used in it:

Incorrect (ARG after FROM):

FROM ${BASE_IMAGE}
ARG BASE_IMAGE=ubuntu:22.04

Correct (ARG before FROM):

ARG BASE_IMAGE=ubuntu:22.04
FROM ${BASE_IMAGE}

Note: ARG is the ONLY instruction allowed before FROM. All other instructions (ENV, RUN, LABEL, etc.) must come after FROM.

Ensure the variable name in the ARG declaration exactly matches the usage in FROM:

Wrong (typo):

ARG BASE_IMG=ubuntu:22.04
FROM ${BASE_IMAGE}

Correct:

ARG BASE_IMAGE=ubuntu:22.04
FROM ${BASE_IMAGE}

Variable names are case-sensitive, so BASE_IMAGE and base_image are different variables.

Important: An ARG declared before FROM is ONLY available in the FROM instruction itself. After FROM, the ARG value is lost and must be re-declared:

ARG BASE_IMAGE=ubuntu:22.04
FROM ${BASE_IMAGE}

# This ARG re-declaration is needed to use the value after FROM
ARG BASE_IMAGE
RUN echo "Built from: ${BASE_IMAGE}"

The re-declared ARG inherits the value passed via --build-arg but does NOT inherit the default value. If you need the default after FROM:

ARG BASE_IMAGE=ubuntu:22.04
FROM ${BASE_IMAGE}

ARG BASE_IMAGE=ubuntu:22.04
RUN echo "Built from: ${BASE_IMAGE}"

If builds work locally but fail in CI/CD, ensure your pipeline passes the required build arguments.

GitHub Actions:

- name: Build Docker image
  run: |
    docker build \
      --build-arg BASE_IMAGE=${{ vars.BASE_IMAGE }} \
      -t myapp .

GitLab CI:

build:
  script:
    - docker build --build-arg BASE_IMAGE=$BASE_IMAGE -t myapp .
  variables:
    BASE_IMAGE: "ubuntu:22.04"

Docker Compose:

services:
  app:
    build:
      context: .
      args:
        BASE_IMAGE: ubuntu:22.04