Ask a room of Nigerian structural engineers which code they design to and you will not get one answer. You will get a client who wrote BS 8110 into the brief, a lecturer who taught EC2, an approving authority with its own habits, and a senior engineer who has had a spreadsheet since 2006 and has no intention of retiring it.
That is not confusion. It is a profession mid-transition, and it will be mid-transition for years yet. Software that forces the question early is just adding a problem.
The code is a setting, not an architecture
Movastruct keeps the model and the code apart. The beam is a beam: a span, a section, supports and loads. Which code we check it against is a decision you make afterwards, and can remake in a click.
So the same beam can be designed to BS 8110 for the client who asked for it, and re-run against EC2 to see what changes — the same afternoon, without re-entering a single number. Usually the difference is a bar. Sometimes it is a depth. Occasionally it is nothing at all, and knowing that is worth something too.
What we will not do
We will not silently substitute one code for another because we happen to have implemented it better. The report says which code it was designed to, on the first page, in a size you cannot miss. A calculation whose code has to be inferred is a calculation nobody should accept.
And when the codes genuinely disagree — the shear provisions are the usual offender — we show you both and let you exercise judgement. You are the engineer. We are the tool.