IDE: Relaunch 64
This is a Java-based IDE that is purpose-built for Commodore assembly language programming. It supports a number of editing features that are very helpful, and also supports the unique syntax of several popular Commodore assemblers.
I've never used KickAssembler before for a personal project, but I've heard it kicks - well, you know. The clear and well layed-out documentation looks like a definite plus.
Really, there isn't much other choice for a Commodore 128 emulator. I am using one of the recent nightly builds of VICE, so I get the cool new features and bug fixes, a couple of which are very important for the 128.
Test of the build chain
Here's my "Hello World" (more like, "A"):
.pc = $2000
Assemble, then from BASIC:
searching for dooey.prg
We are off to the races!