You can also look up for these other topics:
Framework
Coding Standards
Boilerplate
CMS
Tool
Security
Hacktoberfest
Adds extra security-related features in your Symfony application
nelmioBuild Content-Security-Policy headers from a JSON file (or build them programmatically)
paragonieOWASP Vulnerable Web Application Project https://github.com/hummingbirdscyber
OWASPthis repository is a docker containing some "XSS vulnerability" challenges and bypass examples.
moeinfatehi