As a Service schema 
+----------------+
|      IaaS      |
|       VM       |
|       VPC      |
+----------------+
        |
        |
        V
+----------------+
|      PaaS      |
|   Managed DB   |
+----------------+
        |
        |
        V
+----------------+
|      SaaS      |
|     GitLab     |
| Shared hosting |
+----------------+