A Full stack developer is someone able to handle and develop both the Frontend (client side) and backend (server side) of an application. He/She must be able to switch and solve problems relating to both Frontend and backend development and must be conversant with technologies like:

1. HTML
2. CSS
3. JavaScript 4 .A frontend framework
4. Server programming language e.g python, Java.
5. and a database

But this coming year which is 2021, bars has been set high and new skills are required to actually fit the position of a full stack developer, as a full stack developer you need to not only be able to handle both Frontend and backend tasks but also be conversant with the following technologies

1. DevOps
2. Cloud computing
3. UI UX design
4. CI/CD
5. Mobile app development
6. CMS - content management system
7. Containerization (Docker)
8. Container orchestration

Note: this post is simply based on my opinions and research I've carried out

What would you add?