SDL2 is pretty easy, and I have some examples. No clue about vulkan, though.

Assuming you have SDL2 dev libs installed on your system:

• “Find” files (used by cmake to find the libs on your system)
• Pointing cmake to the Find files
• Using find_package to bring the source files into the project
• Adding SDL2 includes to a target
• Adding SDL2 libs to a target

For an example of how to do a minimal C++ executable target, this might be useful.

By far the simplest for small projects is not to bother building incrementally, but instead do a full build each and every time. That is, make a script that simply performs all build steps, one at a time, using hard-coded paths and library names, eg

#!/usr/bin/env sh
set -e -u -x

CCFLAGS="-Wall -g"
FLEXFLAGS=

bison --defines=tokens.h --output=parser.cpp parser.y
flex $FLEXFLAGS --outfile=scanner.cpp scanner.l

g++ $CCFLAGS -c -o parser.o parser.cpp
g++ $CCFLAGS -c -o scanner.o scanner.cpp
g++ $CCFLAGS -c -o encode.o encode.cpp
g++ $CCFLAGS -c -o ast.o ast.cpp
g++ $CCFLAGS -c -o image.o image.cpp
g++ $CCFLAGS -c -o output.o output.cpp

g++ $CCFLAGS -o encoder parser.o scanner.o encode.o ast.o image.o output.o -lpng

I name these files typically mk.sh, and besides building the program, they also function as a reference what to do.

Only when you want to be portable, or when you want to build incrementally, it becomes really useful to invest time in some kind of build system.