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Validates that the platform of an external base image matches the expected target platform.
PropertyValue
SeverityOff
CategoryCorrectness
DefaultDisabled (superseded by tally/platform-mismatch)

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Tally behavior deviation

Tally disables this rule by default because its host-dependent design is fundamentally broken for a static linter:
  • Non-deterministic results across machines. The rule compares resolved image platforms against the host’s default platform (via runtime.GOARCH). The same Dockerfile produces different violations on linux/amd64 CI vs macOS/arm64 developer laptops.
  • False positives on Windows containers. The expected OS is hardcoded to "linux", so any Windows base image (e.g., mcr.microsoft.com/windows/servercore) is always flagged as a mismatch.
  • Fires without explicit intent. When no --platform flag is set on FROM, the rule still compares against the host — even though the builder will pick the correct platform at build time.
Use tally/platform-mismatch instead. That rule only fires when --platform is explicitly set on FROM and the registry does not provide the requested platform, producing deterministic results regardless of host. You can re-enable this rule via configuration if you prefer the BuildKit behavior: 
rules:
  buildkit/InvalidBaseImagePlatform:
    severity: error

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Description

When using --platform or $TARGETPLATFORM, this rule checks that the base image actually supports the requested platform by resolving image metadata from the registry. This is an async rule that runs with --slow-checks, as it requires resolving image metadata from the registry.

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Examples

Bad (image not available for requested platform): 
FROM --platform=linux/s390x ubuntu:22.04
# Error if ubuntu:22.04 is not available for linux/s390x
Good: 
FROM --platform=linux/amd64 ubuntu:22.04
The error message includes available platforms: 
Base image ubuntu:22.04 was pulled with platform "linux/arm64", expected "linux/s390x" for current build

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See also