Spend the next few months learning about a domain (backend, frontend, platform, etc), then find "creative" ways to incorporate it in your CV.

Talk to everyone you have worked over, under, and beside.

There is a common expectation that senior people should be able to get senior positions through networking because it implies that the person is someone people want to work with again.

The more senior the position, the more this expectation exists, e.g. corporations don't list CEO on the we-are-hiring link.

Know all there is to know about the platform

That's table stakes. People skills are how to consistently win the pot. Good luck.

Can you move within your current organization? Even 25% of your time? Are there teams that need help that use a technology you'd like to move toward.

This type of a role shift is often an easier sell than being hired for tech new to you by a new organization.

I'd frame it less as "I want to stop doing SN work" and more like "I'm looking to grow my skills to be more valuable to the company".

Why do you want to switch?

If you've been there a while and have some latitude start a 'Labs' initiative.

I've been doing this at every company I work at. Ask for 10% or 20% time to spend building prototypes to leverage technology to solve problems that provide a huge value to your org.

Compile a list of problems and look for the lowest lift and highest value to org.

Build one and if it's a success you'll get full buy in.

You can pick the stack you want to work with and integrate with ServiceNow as needed. Not familiar with service now but there are always things you can do with multiple stacks/services that provide value to the org.

Maybe this will scratch your itch and possibly open up a new position/group you could develop inside and run.

I do not recommend full-stack. You will find all the same frustrations plus working with uncertified entitled people who generally aren’t good at what they good.

I'd consider this carefully given the state of the market. It is much easier to move around when demand (for SWE) is high. When demand is low, companies will prefer people with specific expertise. There isn't much you can do about that.

Another alternative is to start your own thing/consulting. I'd do this on the side until it is profitable enough to pivot.