Both `steam-engine` and `building-hacks` are plugins that affect buildings, but they are not the same. Much of the low level logic will probably still work for both plugins, but the UI components will need a makeover.
Ok. I was mainly asking if building-hacks could be used to reimplement steam-engine.
Edit:
After looking at it, I think the problem is in getting a non-magma-based “steam-engine” to start producing power whenever a custom reaction starts and stop producing power a certain number of ticks after the reaction ends (with the possibility of continuous power output if a new reaction is started quickly enough). My suggestion is to rename mod-tools/reaction-trigger to mod-tools/reaction-trigger-end and add an option to have it optionally trigger a certain number of ticks after the reaction completes, as well as to add a new tool called mod-tools/reaction-trigger-start that would run commands when a reaction was started.
Edit2:
Just realized that mod-tools/reaction-trigger is UNAVAILABLE. still might be a good idea though. On third thought, I think what’s needed is to extend eventful to include an onReactionStarting() event. Now if only there was a way to get DFHack to run Lua code when a mod was loaded…