As it is hard to split my skills on only Admin or Developer ones, I find it easier to list them chronologically as they came in my life. And I won't bother on my hardware skills as they are much more than an amateur one but far less than professional. I did lot of networking setup e.g. routers, switches... but not just programming and creating schema, but wiring, soldering... Still I did it out of curiosity and because I like to understand the process.
My first development skills were in my primary and secondary school. Mostly writing apps to solve mathematical problems - geometry, trigonometry and functions. I did these tasks in: Basic, GWBasic and QBasic.
During my university studies I did some smaller projects in Turbo Pascal and Delphi Pascal, C, Prolog, MS Visual Basic, Fox Pro, but the more serious and useful ones I developed in C# and Visual C++. After this for few years I used the later ones on smaller projects I developed, with focus on C#.
At that moment I was still impressed with Data Centers and what we will know today as cloud. Not to say that my final work on University was actually on topic of Data Centers.
So I started professionally setting up servers, workstations and networks. In the beginning MS Windows 2000, 2003, 2003R2, 2008. With file sharing, Share Point, Team Foundation Server, MS-SQL 2005/2008 and learned batch scripting.
Soon I learned the advantages of Linux technologies and I learned bash scripting, ftp, mail, etc. All up to virtual machines setup. Mostly used KVM/qemu and VirtualBox. I interacted with lots of various distributions but when it came to deployment I usually stick with Ubuntu, Debian and CentOS. I use them for more than a decade and they showed them selves as trust full partners from various reasons.
At the same time I tried some curiosity projects in Unix namely openSolaris and freeBSD, just to prove my self that I can do it if I have to.
I will only mention that I did setup and administration of services like Google G Suite, Office365 and similar cloud offering, for my clients.
Since my first professional project till this day I have to work actively with SQL and data bases. As I have already mentioned MS-SQL, I will just add PosgreSQL (some basic smaller projects) and huge professional experience in MySQL and SQLite.
As the cloud started taking over and my curiosity got satisfied I saw that it is time to primarily focus on software development. Open source technologies and various platforms I used made me choose my next tool set. Qt C++ and Python.
I developed few large multi platform monolithic server / client applications in combination with MySQL and single user ones with SQLite. With complete GUI.
For micro services, process automation and data projects I use Python with libraries like pandas, sqlachemy, pymysql, xlsxwriter, openpyxl...
Currently I'm improving my skills from data manipulation with pandas - online certification. I'm enrolled on multiple machine learning courses. And I started learning Kotlin and interested in enrolling Java course after that.