blueoriginsoftware

Yes, for safety-critical code, we have to plan for and handle every possible failure mode. There is also flight and ground code that isn't safety-critical. And obviously we have a lot of software at the company that supports engineering and analysis. Not everything gets developed to the same rigor because rigor takes time.

You're right that you can't predict every possible failure and typically you also can't test every possible combination of inputs and outputs. The single best way to mitigate that is to architect systems that are inherently simple. That means isolating systems from one another and keeping the safety-critical surface area small. Fewer failure modes means fewer cases to analyze and handle. After that, though, we make sure our systems are really well understood, with documented interfaces, requirements, designs, and tests, in addition to the code -- with review of all of those. We measure code coverage, invest in static analysis, use continuous integration, etc. It's all about making the systems simple and well-understood.

For testing of the flight code, we test at multiple levels -- unit and component testing, integrated simulation, the full hardware-in-the-loop setup, and even some on the vehicle (e.g. we can make the vehicle think it's flying when it's still on the ground). The hard part is making sure we've covered everything that has to be covered. For that we rely primarily on human review and code coverage analysis.

Or maybe exactly the right amount

I for one never expected to work in the space industry or Blue. I was previously working at Amazon and heard a lot of mentions of Blue. I thought since I didn't have a big mechanical/electrical engineering background I wouldn't be able to find a job in the field.

I saw that Blue had software opening that matched my background(CS Degree) and applied and got on a great team building applications/tools that drives the business of building rockets.

The interview for Blue is different than any other I have been to before as the first hour is you giving a presentation on yourself, job history, and projects.

So don't let your dreams be dreams! Just DO IT!

Yes, many of us do.

Yes, we do :)