Depending on where I worked we either used Postman mocking or json-server. I really liked json-server as it quickly gives you CRUD endpoints.
Shameless plug: I created another mocking tool Mockoon, a desktop app for quick REST API mocking. It's open source and there is a CLI to run your mocks during integration testing.
I recently started working on adding GraphQL too.
json-server would be good for your use case I think.
Shameless plug: I created mockoon an open source desktop API mocking tool. The approach is a bit different and more about quickly mocking any type of rest endpoint, without much constraint.
Would be interested too! I started looking into this for my app (https://mockoon.com) but I am definitely not a MacOS user nor developer, and I just don't understand most of what is related to this ecosystem :D
You could use a tool like Mockoon to mock and API endpoint. I'm not sure if that's what they're asking for.
Then to test, simply follow a rest assured tutorial and give it the URL for your mockoon server. I agree with the basic tests that u/noganetpasion gave.
I'm not sure what kind of works you're doing. For UI or local AJAX design, nothing can stop you from making a local copy of codes and do everything on your Mac. You can setup a personal GitLib account and keeps everything synced, or you can make a remote Git repository on iCloud or DropBox synced folder and do local syncing.
If you need to call RESTful APIs, you either make an easy stub with tools like Mockoon or you just make a 5-minutes server in Node.js using static response sets. You can also choose to expose APIs on your local Windows PC to the internet via services like ngrok. Or you just build the service locally on your machine, unless it's running on complete server farm environment like J2EE.
P.S. Before you're doing so, check your employment contract. Some employers may forbid employees to carry project related data out of office or doing anything that may bypass the company firewall.
I can speak about my humble experience with maintaining an open-source project while having a full-time job and a family. It's a lot of work. For two years and a half now, coding, debugging, thinking about the next feature implementation, triaging the issues, and more and more of: answering the support requests, writing articles to make to project grow, updating the documentation, etc.
It has brought me a lot of great interactions, new skills, and tremendous satisfaction. But it's still a lot of work, and one must be prepared for the long haul.
(My humble open source project, an API mocking tool: https://mockoon.com)
As a maintainer of an open source project, I can say there is no good or bad contribution. All help is welcome. The only thing that you should keep in mind is that you must be prepared to amend your contribution. You can't just push some code in a PR and expect it to be merged right away. You may need to modify the code, add missing tests, follow how it's done in the rest of the codebase, etc.
I must say that for me, having people contribute is nearly as much work as doing things by myself. It requires lots of discussion about the implementation, best practices, following the code style, etc. But still, I really like that because it makes me challenge myself, my (bad) choices, my (bad) code, etc :)
(My open source project: https://mockoon.com - Desktop API mocking tool)
There are many solutions to mock the backend. Returning mock JS objects in your services is the quickest one.
There are also software/cloud services that allow you to mock APIs. Just replace your Backend URL with the software's URL.
Shameless self promotion: I created Mockoon (https://mockoon.com), a free and open source desktop application that exactly does this. You can also use it as a proxy between your front and backend. It will log every entering request that you can then mock in one click. You can also find more or less the same features in Postman and a dozen other apps and online services.
An example with my application Mockoon (https://mockoon.com) which not very big but still has many features: - binaries size between 50 and 60MB - 5 processes when running - around 100 MB RAM taken
I've signed my electron app (https://mockoon.com) for windows with a Digicert certificate, using Electron Builder. It worked perfectly. But start from this page: https://www.digicert.com/friends/sysdev/ you get a discount on the certificate. Digicert is the cheapest I've found (but still recommended on Microsoft website, I am not sure how you can trust discount certificate providers...)
For mac, I heard that last versions of Gatekeeper only allows Apple certificates, that's why I did not go for a certification authority like Digicert but rather enroll for Apple developer program. https://developer.apple.com/programs/enroll/ It's 99€ / year so basically the price of a "normal" certificate. I also signed it with Electron Builder.