# **baseline**: integrate into a huge project Baseline allows you to remember the current project state and then show only new errors, ignoring old ones. First of all, let's create baseline. ```bash flakehell baseline > baseline.txt ``` Then specify path to the baseline file: ```toml [tool.flakehell] baseline = "baseline.txt" ``` Now, `flakehell lint` command will ignore all your current errors. It will report only about new errors, all errors in a new code, or if old line of code was modified. ## Running flakehell against diff Flake8 has `--diff` option to run checks only against specified diff. FlakeHell also supports it but additionally allows you to mix it with explicitly specified paths. For example: ```bash git diff | flakehell lint --diff my_project/ ``` Example of running [flake8-annotations](https://github.com/sco1/flake8-annotations) on [GitLab CI](https://docs.gitlab.com/ee/ci/) only against changed code in `my_project/`: ```yaml flake8-annotations: image: "python:3.7-buster" stage: test rules: - if: $CI_MERGE_REQUEST_TARGET_BRANCH_SHA changes: - "my_project/**/*.py" script: - pip install flakehell flake8-annotations - git diff $CI_MERGE_REQUEST_TARGET_BRANCH_SHA | flakehell lint --diff my_project/ ``` This option also can be mixed with baseline.