What are your tips on choosing domain name? .dev or .com?

In terms of a marketing presence - the .com tld is the gold standard. You can have any other domain of course, but if you're dependent on your target market finding your website, .com is what's most intuitive.

Outside of that use case, things are more flexible. How I've approached using different tlds:

• .io => I've used this for products before but these days I tend to use the tld at an org for internally-facing applications and services. I will host things like Metabase (business intelligence), internal status page, IT, or tools other departments are using.
• .dev => Given how new this tld was, I was able to pick up my last name mainwaring.dev for my personal sandbox. As an organization, I now use .dev domains for engineering services like deployments of feature branches, testing environments, and cloud dev environments (coder/codespaces).
• .app => So far I've only used this tld to play defense; as a brand, you tend to buy up domains to prevent spoofing/phishing and ransom squatting, but I intend to use this tld for future products as the production instance of the service.
• Regional/Country tlds (.eu, .us, .ca, .uk, etc) => When you start scaling into other regions, the architecture of your application may require a separate instance to comply with country or regional regulations. I haven't implemented this strategy yet but it's been a recurring conversation given how many data waivers I've had to sign for my European customers. Important note: Some of these tlds have residency requirements, you/your org may be required to have a physical presence. I encountered this trying to secure .eu, but thankfully I had just acquired a company with a European office.
• .space => So I don't really have a specific purpose for this one, rather I capitalized on pairing the noun tld, picking up knowhere.space, a reference to the fictional space station from Marvel's Guardian's of the Galaxy.

Since your website is related to developers, I think .dev should be fine. Developers most certainly see that top level domain often enough. It seems to be getting popular for developer portfolio sites.

Marketingwise, I'd say choose whatever make sense they all work the same. Some domain have restriction, mainly country one.

Outside of that if you intend to be sending email from that domain, it might be useful to dig a little bit more. I know that our domain is in .buzz and we have done issues with spam filter that we believe come from that. In any case I'm sure we would be able to sort it out if we do the required effort.

Have you tried a .io domain?

Many people 30 and under are warmed up to them, since that's where a lot of cool tools/games/ai is launched.

If the website is related to development then .dev is a good choice.

Yes that's actually my main concern. Sometimes because of the domain your email might become the problem.

Thinking in socketify.dev for github.com/cirospaciari/socketify.py and github.com/cirospaciari/socketify.rb