The development will appear as a built-in feature rather than a standalone app, and the company has revealed work is ongoing after its initial announcement back at the annual F8 conference in May.
App researcher Jane Manchun Wong first discovered evidence the social networking site had been internally testing the service, including screenshots giving future users hints of what to expect.
It appears employees are being encouraged to create fake accounts - which will be purged upon launch - to help with the process.
One screen reads: "This product is for US Facebook employees who have opted-in to dogfooding Facebook's new dating product.
"The purpose for this dogfooding is to test the end-to-end product experience for bugs and confusing UI. This is not meant for dating your coworkers."
It looks like there will be privacy settings to limit who can and can't see a specific user's dating profile - as well as the option of having separate profiles for using Facebook normally or with the new service.
Meanwhile, it appears users will also be able to select non-binary and trans options for both gender identity and desired matches.
Obviously as the product is still in testing, these features - and the look of the service - could changed by its launch date, which is yet to be announced.