Lifelong software project – what technology to choose?

Hello everyone,

since 2014 I’m playing with an idea to build and maintain an app for my own needs (I don’t want to disclose them here, sorry). Over the years I do research of the topic and recently concluded that it becomes a lifelong project to me.

So here I am wanting to bild such app, but I’m not sure which technology / approach to choose which will let my code survive in the next 40-50 years.

So far I know only one example which successfully passed its 30th anniversary – Wolfram Mathematica. I think, it survived and still in the active phase of development due to the fact that is has its own internal programming language. I see the Mathematica app as a huge compiler / interpreter for the internal language + IDE.

Ok, there is another one example – the linux kernel, but I’m not sure how I can explain why it succeed as a software project. And it is not an app.

I think, I have to go the same way. I should try to make my app independent from the underlying technology (to some degree, of course) – design a language first and then use the best available tools and any programming language (probably, statically typed?) to make it work.

What are your thoughts? Are you aware about apps or approaches or methodologies which will help me to actively develop the same app for the next 30-40 years (at least) without rewriting it from scratch after every major technology change?

small note: I am a software developer with 15+ years of experience (backend) and Master degree in CS. The longest period I worked on the same codebase is 5 years.