Well as someone who hires developers let me explain what is important to me...
Your past portfolio
To be honest, there is very little I care about the portfolio itself. It doesn't really matter WHAT you created whether boring or exciting. The only perks here is if it was something related to what you'll do for me and/or does it demonstrate the work you'll do for me is something you would enjoy... Honestly past that shrugs there's just more important things that come first.
But... then why do you ask what I've done?
It's almost a given I will ask you about the last few projects you've worked on. I actually don't really care about the project in itself... I'm assessing several things with these questions. What about the project was important to you, and do you feel is relevant to me.
I also will ask questions about things that went well, problems you faced, and things you may have done differently. Again, none of this is because I care about the project itself, it's I care about you demonstrating critical thought, problem solving skills, etc. I'm assessing what I should expect from you if I hire you.
But it was SOOOO cool!
Hey, I hear you. I have a project that while technically was unimpressive actually made a notable difference in the community. Specifically improving education for troubled students. I literally got to watch first hand this tool change people's lives for the better, and the level of pride I have in that work could have me talking about it for HOURS!!!
Unfortunately the only thing potential hires get from me for chatting about that is.
- I have a passion for education
- I greatly value purpose in my work
- I have a very detailed and methodical approach to my work
The first two items will almost never be bad, but with most employers they'll only be a trivial plus to neutral. (unless they are hiring me into a position in education that they feel will provide me purpose, in that scenario this would be a home run)
The third item is what really holds value, again some places this is a very desirable trait. The sort of places who value taking a little longer to do it right the first time, but for the fast do it now, fix it later places, this could actually count against me.
Discuss what's relevant
If I ask you what makes you passionate about your past work (or proud or similar) this is when you can try to wow me with that arduino work. Sadly I have no practical applications for it in my office so it's of no benefit to me, this is more me getting to know what makes you tick to see if I think you'll mesh well with my current staff. At the same time you could tell me you love sky diving which has zero potential for usefulness to me... but if I happen to have other sky divers on the team that is promising you'll all get along well.
Your github rarely has much value to potential employers, exceptions DO exist. Case and point being the education program I spoke of. To 99.9% of employers it's frankly a waste of time to mention sadly, but if I interview for a job in education, and or work intended to help the community the passion I have there would make me a rockstar candidate.
Most of the time your portfolio has limited value, but let's say you have a passion for ardunio sketches and that guitar was something you have a deep sense of pride in. Perhaps there is a job where someone needs a person to make arduino sketches of various rockstars jamming on their guitars. (Honestly I can't see a scenario this makes sense but hey marketing is not something I "get") In this unlikely scenario your portfolio probably bought you preferential treatment where the only thing standing between you and job is an interview.