Pre-commit.

Also, run it in CI.

.gitlab-ci.yml

+---
+include:
+  - project: shore/ci-templates
+    file: templates/docker-compose.yml

.pre-commit-config.yaml

+---
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks.git
+    rev: v3.4.0
+    hooks:
+      - id: check-added-large-files
+      - id: check-executables-have-shebangs
+      - id: check-merge-conflict
+      - id: check-symlinks
+      - id: trailing-whitespace
+
+  - repo: https://github.com/Yelp/detect-secrets
+    rev: v0.14.3
+    hooks:
+      - id: detect-secrets
+
+  - repo: https://github.com/adrienverge/yamllint
+    rev: v1.25.0
+    hooks:
+      - id: yamllint
+
+  - repo: https://github.com/amperser/proselint/
+    rev: 0.10.2
+    hooks:
+      - id: proselint
+        types: [plain-text]
+        exclude: LICENSE
+
+  - repo: https://github.com/executablebooks/mdformat.git
+    rev: 0.5.3
+    hooks:
+      - id: mdformat
+
+  - repo: https://git.shore.co.il/nimrod/shell-pre-commit.git
+    rev: v0.6.0
+    hooks:
+      - id: shell-lint
+
+  - repo: https://github.com/shellcheck-py/shellcheck-py.git
+    rev: v0.7.1.1
+    hooks:
+      - id: shellcheck
+
+  - repo: https://git.shore.co.il/nimrod/docker-pre-commit.git/
+    rev: v0.3.0
+    hooks:
+      - id: hadolint
+      - id: docker-compose

README.md

 # sogo-docker
 
+[![pipeline status](https://git.shore.co.il/shore/sogo-docker/badges/master/pipeline.svg)](https://git.shore.co.il/shore/sogo-docker/-/commits/master)
+
 Dockerized setup of the [SOGo](https://sogo.nu/) groupware.
 
 ## License