Why roll your own?

Why should a developer use their own code when there's a ton of high quality open source already out there?

I hear a lot of different reasons:

1. It's too hard to learn someone else's stuff.
2. How do I know it is good?
3. How will we maintain it?  If there are bugs, I have to be able to fix them.
4. It doesn't fit our design.

All of these are good reasons IF in fact, they are good reasons.  Too few do the work to figure this out.

1. It is easier to write and understand your own code base than it is to understand what someone else did.  But most people don't even try.  Look folks, this is why they pay you the big bucks ... to understand complex stuff.
2. You have to look at it.  And I mean really look.  There are a lot of ways to find good stuff.  Is anyone else using it? That's a good sign.  Is it frequently updated? Another good one.  Does it have a vibrant community around it? Another good one.  If the last update was two years ago, you may be SOOL (it's an acronym that basically means out of luck).
3. That's one of the cool things about maintenance if you find good Open Source because a vibrant open source community will both accept and fix bugs.  And if you are serious (and I mean truly serious) about #1, and choose that source base, you'll also become a contributor back to it.  So not only can you adopt the fixes of others, but you can also make your own fixes.
4. This can often be a problem.  How flexible is your stack?  How many more dependencies can you take?  If you have a good stack, you are much more likely to find open source that fits onto it without additional dependencies.  You may be challenged around upgrades stack components though, and that's where contributing back becomes important.

What's the value here for adopting open source?

• Time To Market -- Adopting somebody else's code can let you focus on other things that are necessary to bring your product to market.
• Maintenance -- It isn't just new development that you could be saving, it might also be on maintenance.  A good open source project will also maintain the solution for you.  And that has tremendous value.  Software costs are often quoted as 20% development, 80% maintenance.
• Reputation -- Using good open source can enhance the reputation of your own products (if the open source base has a good reputation).  Contributing back can also be a significant reputation enhancer for your organization.

How does this fit in with standards?  A lot of open source projects integrate using standards. Some even BECOME standards (e.g., Schematron).  That's one of the values of standards.

Tomorrow, I'll talk about some cool new open source projects for CDA.

   -- Keith