I would first determine if your source code really warrants the effort needed to keep it secure from prying eyes. We've evaluated several factors including the source code, the service built leveraging that codebase, the people involved in the execution, and the business plan that mixes everything together. For us, in every scenario we could model the value generated by the code was much higher if it were open-sourced.
For example, because the code is open to all, the developers are motivated to produce much better documentation and testing harnesses, usually before they actually do the code itself - internal costs go down. This pays for itself many times over in time saved during debugging and deployment.
Another example is that we've received a lot of critical peer review of our code which has helped us catch and fix flaws in our security and design - internal costs go down, public perception of security becomes positive.
In my experience and market research, it is nearly always the execution of the business that significantly outweighs any super-secret Python methods I may have thought were cool at 2am :)
For example, because the code is open to all, the developers are motivated to produce much better documentation and testing harnesses, usually before they actually do the code itself - internal costs go down. This pays for itself many times over in time saved during debugging and deployment.
Another example is that we've received a lot of critical peer review of our code which has helped us catch and fix flaws in our security and design - internal costs go down, public perception of security becomes positive.
In my experience and market research, it is nearly always the execution of the business that significantly outweighs any super-secret Python methods I may have thought were cool at 2am :)