Nature Inspired Testing Thoughts

Ever thought about DNA? I mean, the fact that DNA is a way to store executable instructions? That sounds a lot like code.

This talk is an exploration of what Nature can teach us about testing software.

Notes by slide:
Slide 6)
Adenine [A] can only pair with Thymine [T]
Cytosine [C] can only pair with Guanine [G]

“It [DNA] generally repairs mistakes in the placement of bases as it replicates itself. This repair work is performed by DNA Polymerase, the enzyme that helps catalyze construction of new DNA from single strands.”

“If an adenine is mistakenly set in place to become linked with a guanine (not its correct partner), the polymerase recognizes that mistake, backtracks by one pair, fixes the mismatch, and then moves on. So the rate of mutation in most DNA viruses is relatively low.”
From Spillover pg. 237

Image Attribution: http://commons.wikimedia.org/wiki/DNA#mediaviewer/File:DNA_chemical_structure.svg
Madeleine Price Ball

Slide 8)
RNA can form a double helix, but is still not as stable (ribose vs deoxyribose).
RNA is a single stranded molecule, generally, with a single base.
Uracil represents the [U] in RNA. It usually takes the place of thymine.

Image Attribution: http://commons.wikimedia.org/wiki/File:RNA-Nucleobases.svg

Slide 10)
The enzyme employed by RNA viruses, on the other hand, is “error prone,” according to Eddie. “It’s just a really crappy polymerase,” which doesn’t proofread, doesn’t backtrack, doesn’t correct erroneous...

Transcript

1. @rainforestqa rainforest Nature Inspired QA Thoughts By Paul Burt (a very handsome mans)
5. @rainforestqa rainforest DNA vs RNA and their Transcription Polymerases
7. @rainforestqa rainforest DNA … + is strongly typed. + has unit tests. + is slow (harder to change).
9. @rainforestqa rainforest RNA … + is weakly typed. + does not test. + is fast (easy to change).
10. @rainforestqa rainforest RNA’s Transcription Enzyme Is “error prone […] It’s just a really crappy polymerase,” From Spillover, pg. 273
11. @rainforestqa rainforest Enter the Eigen Paradox! A Mathematical proof that says...
12. @rainforestqa rainforest Aw, Shit!
13. @rainforestqa rainforest You tell ‘em, Manfred Eigen!
14. @rainforestqa rainforest The Take-Away • Scripts and other tiny software? Ok to roll without tests. • Multi-file projects? You MUST test.
15. @rainforestqa rainforest So yeah, it’s hard. Fear not, JFK offers inspiring words: “We choose to go to the moon [write tests] in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills…”
16. @rainforestqa rainforest Tent Caterpillars and Gypsy Moths Boom and Bust Cycles
18. @rainforestqa rainforest Q: What happens when a bug catches a bug?
19. @rainforestqa rainforest Why the Boom and Bust? • Predation?
 • Food scarcity or abundance?
 • Venus is in retrograde motion?
21. When a caterpillar wanders through a prior infection, it too becomes infected, then melts. The resulting melt drips on leaves. It’s neighbors (likely) become infected. Big population = Big problems
22. @rainforestqa rainforest The Take-Away • Some bugs are only revealed in large sets. For example, lots of users. • If you’re seeing erratic and seemingly random behavior in a bug report… • It could be a melty bug! • (bugs interacting with bugs)
23. @rainforestqa rainforest Adapt or Atrophy Our History n Frogs, Fish, and Everything
25. @rainforestqa rainforest Re-using code = Hello bugs
27. Human Shark
28. The Take-Away Generally: It’s easier to modify something that exists, than to build it from scratch. Adapt, don’t create. That said... adapting is a shortcut. Shortcuts lead to bugs of their own. When bugs appear knowing why helps. Fixing the problem is often significantly easier.
29. @rainforestqa rainforest In Diversity, We Find Strength Stay away from your cousin
31. @rainforestqa rainforest Emacs vs Vim Python vs Ruby iOS vs Android
33. • Really, Natural Selection? • Yup.
34. Competition = Strength • (Even with competition, life is still relatively fragile)
35. @rainforestqa rainforest Take something out of it’s intended environment and … OH HAY, THATS Y U DO 
 12FACTOR APP!
36. The Take-Away Drift between teams / programming philosophies can be beneficial (breeds strength!) Don’t get carried away, though. Taking a creature (or piece of software) out of it’s native environment can have bad effects. Use common sense.
 Small drifts between highly similar products will drive fierce competition. Can be a great natural motivator.
37. @rainforestqa rainforest GMO, Hell No! Intelligent Design -- No, really
39. @rainforestqa rainforest Designing for any ONE attribute will lead you into a corner.
41. Software Analogues Making changes to code means you increase your ‘Unknowns’. Old features will break after making a change. It’s ok! Don’t need to fix it all, just need to know about it. Together, we determine what’s acceptable and what is not.

42. @rainforestqa rainforest Prions, Protists, and Viruses Oh My!
46. @rainforestqa rainforest How did we discover viruses? We couldn’t see them. The answer is theory.
47. Famous Viruses Influenza (Birds) Ebola (Bats, we’re pretty sure) HIV (Primates) SARS (Bats) Hendra (Bats) Nipah (Bats) Fuck Bats (!)
48. @rainforestqa rainforest Sterile Environments (ie Simulators) are shit. To find the right bug, the host matters.
50. The Take-Away Like viruses, prions, etc… some bugs are invisible. Bugs appear in every imaginable shape and size. As a result… “Bug Free” software is a unicorn. Simulators are sterile environments. To find bugs, you gotta get dirty (test on device / host).
51. Fin