What happened to
those nice words,
“Software Quality”?

A grumpy
developer’s
perspective

And 4 simple steps

Adrian
Kosmaczewski

Software developer

since 1996

Houston,

“Our society
depends on
software”

Bjarne Stroustrup

Yes, but:

Software Sucks

(some of it)

(mine does)

(sometimes)

500M

Integer overflow

Nobody died

Therac-25

6 people died

Overexposed to
radiation

1982 Soviet Gas
Pipeline Explosion

Largest non-atomic
explosion of history

Bug injected by CIA

1988 Morris worm

First network worm

Buffer overflow

1988 Russian
“Phobos” Probe in
Mars

Bad thruster
deactivation

1992 London
Ambulance System

No official statistics
about casualties

1993 Pentium bug

*giggle*

1998 USS Yorktown

Ship lost in the
ocean

Divide by zero error

1999 Mars Climate
Orbiter

Miles or
kilometers?

1999 Mars Polar
Lander

Vibrations? Cut the
engines!

Geez, it was the
atmosphere... not
the ground!

2000 National
Cancer Institute,
Panama

8 patients die

20 other overdosed

Doctors indicted for
murder

2003 USA Blackout

Race condition

2006 Mars Global
Surveyor

Motor dead? Yes?
No!

Yeah!

Ever heard about
the CHAOS report?
http://www.standishgroup.com/

Status 1994 2006
Success 16% 35%
Challenged 53% 46%
Failed 31% 19%
Source: http://tinyurl.com/yodqnw

What about us?

No space missions

Smaller projects

Similar problems

Software is
expensive

ISO Certifications
are worthless

CMMI certifications
are (less) worthless

Software Quality
theory is boring

Well, almost

Avoid being on
The Daily WTF

4 steps

1. Pass the Joel Test
2. Avoid Open Spaces
3. At least write unit tests
4. Communicate

1
The Joel Test
http://tinyurl.com/1s8w

The Joel Test
1. Do you use source control?
2. Can you make a build in one step?
3. Do you make daily builds?
4. Do you have a bug database?
5. Do you fix bugs before writing new code?
6. Do you have an up-to-date schedule?
7. Do you have a spec?
8. Do programmers have quiet working conditions?
9. Do you use the best tools money can buy?
10. Do you have testers?
11. Do new candidates write code during their interview?
12. Do you do hallway usability testing?

How much is your
score?

Be honest! :)

2
Avoid open spaces

Cheaper?

Why not?
•Noise
•Interruptions
•Phones
•iPods
•Lack of privacy

Ever heard about
“Peopleware”?

Buy it and
read it

“Flow”

http://www.ndesign-studio.com/images/portfolio/graphic/flow-1.jpg

Consequences
•Low quality
•Late delivery
•Burnout
•Turnover

Turnover is your
enemy # 1

Cheaper in the
short term means
expensive in the
long run

3
At least,
write unit tests

You’ll thank me

• JUnit • JSUnit (JavaScript)
• NUnit • WOTest (ObjC)
• PyUnit • PHPUnit
• Unit::Test (Ruby) • FoxUnit (FoxPro)
• RSpec (Ruby) • Selenium
• CppUnit (C++) • lisp-unit
• Boost Test (C++) • DUnit
• Autounit (C) • SchemeUnit

Why?

Easy

Free

Refactoring

Documentation

Usage examples

Maintenance

Architecture

API Design

Performance

Good karma

How much testing?

Enough

Don’t become
fanatic

(at least)
One for every bug

Avoid regressions

Run them at every
build

Script that build!

4
Communicate

Wiki

Blog

Trac

Visual Studio
Team System

(yuck!)

Bugzilla

Meetings

Don’t make them
regular

Make them ad-hoc

Prefer code reviews

Client on board

Not always
possible!

But extremely
useful

Conclusion

1. Pass the Joel Test
2. Avoid Open Spaces
3. At least write unit tests
4. Communicate

Thanks!

Questions?