This is a factorio mod called "Miles' BobsMods Expansion", currently build against factorio 1.1.0 and bobsmods (Whatever Version is newest and present during the 21th June 2022). The mod expands on a few machines such as assemblers and electronic assemblers but also adds a furnace tier between steel and electric: The early electric furnace. Other features are still planned and any ideas can be submitted on github.
This is meant to be used with full bobs but will work with as little as Bob's Library, Assembly, and Modules. Depending on if you use the optional marked mods, the recipes will change accordingly and use the new resources.