How Multi-Stage Builds and Base Image Choices Can Shrink Docker Images Dramatically

Bloated Docker images — sometimes exceeding 1 GB for a small compiled service — slow down deployments, widen attack surfaces, and quietly raise registry costs. Engineers can diagnose the problem using docker history and docker image inspect to identify oversized layers before making any changes. Multi-stage builds offer the largest size reduction by keeping compilers and dev dependencies in a throwaway build stage and copying only the final artifact into a clean runtime image. Choosing a leaner base image, such as a slim variant or distroless image, further cuts size, though Alpine's use of musl libc instead of glibc can cause compatibility issues with some packages. Together, these targeted techniques can reduce image sizes significantly without requiring exotic tooling or deep Docker expertise.