It's interesting how many act and think of themselves as 'developers' when it comes to modding and creation of mods.
If you're a legit developer/programmer (using the programmer def of being both creator and code inputter and compile/test monkey - i.e. both extremes of simple and complex), you are a creator of methods, a coder who creates functional tested algorithms which you eventually finely integrate into larger algorithms or break up into discrete modular examples which work and work to design expectations before you even consider letting any part or whole into the wild.
Outside of programming, you'd be an engineer - those who engineer solutions be it a solution that reliably solves a design flaw or you fully design/engineer to a working stable solution.
Most developers (self-styled, self-appointed status) are none of the above, they range from an advanced copy-n-paste-tweak blunt chisel hack merchant who takes existing resources and makes them work together with no real ability to create any part from the ground up let alone know about optimal design and optimisation of a construct.
But with all that said, whilst many true developers pride themselves on handcrafted code bases and higher functions code use, it isn't necessarily true that no true developer wouldn't use an existing proven code base to build upon. Just as engineers will look to not reinvent the wheel to build a better rolling chassis when they have options of solid proven bases to work with and can focus on optimising it to ready it for use as s skeleton of the bigger build.
So if you're in any doubt about whether your 'developer' status is a product of ego not fact, the above should help you get a cold dose of harsh reality - which for some, is long overdue.