How to automate the build process trigger when commits are pushed in GitLab CI/CD?

To automate the build process when commits are pushed to GitLab CI/CD, a configuration file .gitlab-ci.yml is used, which is placed in the root of the repository. This file describes the stages and jobs that should be executed upon certain events, such as pushing to a branch.

An example of a simple .gitlab-ci.yml for running a build on each commit:

stages:
  - build

build_job:
  stage: build
  script:
    - echo "Starting build..."
    - ./build_script.sh
  only:
    - branches

Here, each push to any branch will trigger the build_job task, which will execute the build script. GitLab Runner will automatically pick up the changes and run the pipeline.

Thus, it is enough to configure .gitlab-ci.yml with the necessary tasks, and GitLab CI/CD will automatically run the build on each commit.