[Wiki]

However, if you've worked for a significant amount of time (e.g., 8 years), then you should show how your work experience prepared and motivated you to come back to pursue a Ph.D., which might be difficult if you've been outside of the research community for too long.
Philip Guo - Advice for preparing to apply and actually applying to science Ph.D. programs

Having long non-research experience above text adds to my worries.

Does contribution to an open source project, related to my research interests, has any significance in context of PhD admission?