I hate marketing though. I'm sure this sounds familiar...
Is there any way to make money from a "side project" or open source development without needing to do marketing campaigns?
Not only am I terrible at it, even thinking about it corrupts my enjoyment of developing new stuff.
If you feel "corrupted" when writing docs, then I'm truly sorry. If not, then just try to reframe it in your mind as "writing docs" for your users. If your audience is technical, then they'll appreciate the emphasis on actual details.
Also, even docs often start with a "dumbed down" explanation of what something does. It doesn't mean devs are dumb. It's just important to communicate the value quickly so that people can decide if you want to dwell deeper.
Basically, your landing page is a summary and your deep dives are the "advanced" pages of your website. It's all possible _without_ marketing buzzwords too!
Beyond that, I'd say blogging is huge too. Just write about stuff you find cool and it'll help get eyeballs on your stuff. It doesn't have to be specific to your product. Just having content that people like helps you build your branding and get some early traction.
Obviously there is more to it than this, but that's at least a good way to help get you out of this "mental rut". Cheers!
I think the best options is one of 3:
1) If your building for fun, do above and the earnings are what they are. You can always bring in marketing down the track if your feeling on this change.
2) If focused on driving a better income, as a the couple people already said in thread, find a marketer that suits you and what you expect from the business. Maybe less product input and they do their thing separate from you. Make that expectation clear in the beginning as it could be a point of friction if its not the expectation.
3) Find a B2B distribution channel. This can be super effective if you find the right one e.g. if your product complements a business and they are happy to recommend it for kickback or because it improves their offering. Hard to find but if you do it can be a one time deal and you keep doing your thing while the product gets pushed in the background.
Good luck with whatever!
If you have money, then you might be able to outsource this if it's too overwhelming. I found a great Facebook ads guy by just going to reddit/r/facebookAds and messaging someone who seemed like they knew what they were talking about.
Another trick is to just make something with a virality score greater than 1. Meaning on average, each user brings in at least one more user. Then you really only have to market to one person (on average ;)
I would posit that you might want to reconsider your definition of "marketing." That is to say, there is a (lot) more to marketing than just "campaigns" that spam people via email, phone, Twitter, etc. or FB ads, Reddit ads, Adwords, and suchlike.
Consider the following:
Marketing is currently defined by the American Marketing Association (AMA) as "the activity, set of institutions, and processes for creating, communicating, delivering, and exchanging offerings that have value for customers, clients, partners, and society at large".[1]
If you accept this definition, you are already doing some "marketing" simply by the act of choosing what to build, and by building it!
Maybe what you really find distasteful is "promotion" which is just a subset of marketing. If so, I'd still posit that you might want to reconsider your feelings a bit. "Promotion" includes everything you do to make people aware that you product exists, and to convey its value to people. If you tell your best friend "Hey, I make this $THING, do you know anybody who might like it", you're already engaging in (very lightweight) promotion. And maybe more to the point, it's very unlikely you're going to make money from your side project without some kind of promotion.
Maybe what you're really railing against is tasteless, generic, low-value, untargeted, spammy promotion? If so, the question is how can you promote your product without engaging in activities that are "tasteless, generic, low-value, untargeted, and spammy". That's tough to answer because it's kinda subjective, but give it some thought, you mind find that you can find a compromise position that works for you.
Another possibility - you might be able to find someone who is particularly interested in / good at, marketing and promotion activities, and partner up with them somehow.
But face it, almost everything that you use, from Logitech mouse, Apple or Lenovo ThinkPad computer, a Lexus or Toyota car is a result of marketing activities, public and media relations.
Now, you can do all that without marketing, but marketing is not only advertising, it’s much more than that. Advertising is just one tactic of marketing.
Or buy something that already has strong SEO and doesn't rely on "active" marketing on ad spending.
Another approach is what Paul Graham said: "Live in the future and then build what's missing". You can start working in a leading-edge area of technology and build things that are missing. Others that are also working the field may be searching for a solution to the same problem and then find your solution.
In any case, it will probably take multiple tries or pivots before you find product market fit.