Technical Excellence - OOP Munich 2015

1
James W Grenning
wingman-sw.com
@jwgrenning
Technical Excellence

OOP, Munich 2015
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Oop@wingman-sw.com
Copyright © 2008-2014 James W. Grenning

All Rights Reserved @jwgrenning.
2

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I Tried to Avoid
Computers
3

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4

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5
People will pay me
to do this?!!

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6

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May 7 11:21:17: --- last message repeated 1 time ---
May 7 11:21:17 Cowboy kernel[0]: IOSurface: buffer allocation size is zero
May 7 11:42:14: --- last message repeated 4 times ---
May 7 11:51:45 Cowboy kernel[0]: nspace-handler-set-snapshot-time: 1336409506
May 7 12:08:58 Cowboy kernel[0]: hibernate image path: /var/vm/sleepimage
May 7 12:08:58 Cowboy kernel[0]: sizeof(IOHibernateImageHeader) == 512
May 7 12:08:58 Cowboy kernel[0]: Opened file /var/vm/sleepimage, size 8589934592, partition base 0x0, maxio 400000 ssd 1
May 7 12:08:58 Cowboy kernel[0]: hibernate image major 14, minor 0, blocksize 512, pollers 5
May 7 12:08:58 Cowboy kernel[0]: hibernate_alloc_pages flags 00000000, gobbling 0 pages
May 7 12:08:58 Cowboy kernel[0]: hibernate_setup(0) took 0 ms
May 7 12:09:01 Cowboy kernel[0]: en1: BSSID changed to 00:40:96:a1:33:c9
May 7 12:09:01 Cowboy kernel[0]: wlEvent: en1 en1 Link DOWN
May 7 12:09:01 Cowboy kernel[0]: AirPort: Link Down on en1. Reason 8 (Disassociated because station leaving).
May 7 12:09:01 Cowboy kernel[0]:
May 7 12:09:37 Cowboy kernel[0]: hibernate_page_list_setall start 0xffffff80d4cff000, 0xffffff80d4f98000
May 7 12:09:37 Cowboy kernel[0]: hibernate_page_list_setall time: 415 ms
May 7 12:09:37 Cowboy kernel[0]: pages 2040801, wire 338507, act 950045, inact 182445, spec 36, zf 113125, throt 0, could discard act 169869 inact 207719
purgeable 38826 spec 40229
May 7 12:09:37 Cowboy kernel[0]: hibernate_page_list_setall found pageCount 1584158
May 7 12:09:37 Cowboy kernel[0]: IOHibernatePollerOpen, ml_get_interrupts_enabled 0
May 7 12:09:37 Cowboy kernel[0]: IOHibernatePollerOpen(0)
May 7 12:09:37 Cowboy kernel[0]: writing 1583874 pages
May 7 12:09:37 Cowboy kernel[0]: encryptStart 4f820
May 7 12:09:37 Cowboy kernel[0]: encryptEnd 108b02c0
May 7 12:09:37 Cowboy kernel[0]: image1Size 474682880, encryptStart1 4f820, End1 108b02c0
May 7 12:09:37 Cowboy kernel[0]: encryptStart 1c4b1600
May 7 12:09:37 Cowboy kernel[0]: encryptEnd b7957b30
May 7 12:09:37 Cowboy kernel[0]: PMStats: Hibernate write took 35189 ms
May 7 12:09:37 Cowboy kernel[0]: all time: 35189 ms, comp bytes: 6487916544 time: 6366 ms 971 Mb/s, crypt bytes: 2882564048 time: 4618 ms 595 Mb/s,
May 7 12:09:37 Cowboy kernel[0]: image 3080027136, uncompressed 6487916544 (535388), compressed 3068648576 (47%), sum1 ec64ffd2, sum2 571d97a2
May 7 12:09:37 Cowboy kernel[0]: wired_pages_encrypted 224499, wired_pages_clear 113814, dirty_pages_encrypted 1245651
May 7 12:09:37 Cowboy kernel[0]: hibernate_write_image done(0)
May 7 12:09:37 Cowboy kernel[0]: sleep
May 7 14:06:05 Cowboy kernel[0]: Wake reason: EC.LidOpen (User)
May 7 14:06:05 Cowboy kernel[0]: en1: 802.11d country code set to 'X0'.
May 7 14:06:05 Cowboy kernel[0]: en1: Supported channels 1 2 3 4 5 6 7 8 9 10 11 36 40 44 48 52 56 60 64 100 104 108 112 116 120 124 128 132 136 140 149 153
157 161 165
May 7 14:06:06 Cowboy kernel[0]: Sound assertion "0 == fAudioEngineArray" failed in AppleHDADriver at line 3163 goto Exit
May 7 14:06:08 Cowboy kernel[0]: Previous Sleep Cause: 5
May 7 14:06:08 Cowboy kernel[0]: MacAuthEvent en1 Auth result for: 00:40:96:a0:63:95 MAC AUTH succeeded
May 7 14:06:08 Cowboy kernel[0]: wlEvent: en1 en1 Link UP
May 7 14:06:08 Cowboy kernel[0]: AirPort: Link Up on en1
May 7 14:06:08 Cowboy kernel[0]: en1: BSSID changed to 00:40:96:a0:63:95
9
The serial output port was notavailable for debug!

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10
Source level debug was there, if
your source was ASM

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11

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12

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My Roots in Agile
13

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14
Kent Beck Ron Jeffries
Ward Cunningham Martin Fowler

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Let’s Have a Meeting
15
Alistair CockburnRobert Martin

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How Did I Find Myself at Agile
Manifesto Meeting?
16
James, do
you want to
go to the
Lightweight
Methods
Summit in
Snowbird?
Skiing!
Sure Bob,
I’ll go….

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17

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Before the
Agile Manifesto
18

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19
MessageProcessor SerialDriver
WaitForString(buffer, length, semophore)
Pend(semaphore)
Post(semaphore)
WaitForMessage(buffer, length)
return
Message
Processor is
blocked,
waiting for
its
characters
Interrupt is
collecting
characters
SemaphoreFake
Copyright © James W. Grenning
<<implementation>>
IO
<<implements>>
+ Read(addr) : data
+ Write(addr, data)
<<interface>>
IO
+ Expect_Read(addr, data)
+ Expect_Write(addr, data)
MockIO
<<hardware>>
+ Program(addr, data)
+ ProtectBlock(block)
+ EraseBlock(block)
//etc
FlashDriver
FlashDriverTest
OurCode
BFw Adaptor
Big Framework
+ send()
+receive
Messaging
+ doSomething()
<<interface>>
OurServiceRequests
<<implements>>
Big Framework
Client

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21

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22
That may not have been
Watts’ intention, but it was the
message that industry was
hearing

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Did that work?
23
Most the industry
suffered from defects,
delays and frustration.

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24

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25
The first and foremost
statement stresses people

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People and Values were Central
to Forming Agile
26

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27
Software development is
not centrally about the
process and documents

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28
static void checkEvent(ScheduledLightEvent* lightEvent)
{
if (randomEventAlreadyHappenedToday(lightEvent))
return;
!
if (!TimeService_MatchesNow(lightEvent->day, lightEvent->minute +
lightEvent->randomMinutes))
return;
!
operateLight(lightEvent);
!
ScheduledLightEvent_Randomize(lightEvent);
preventAnotherRandomLightOperation(lightEvent);
}
!
void LightScheduler_Wakeup(void)
{
int i;
!
for (i = 0; i < MAX_EVENTS; i++)
{
if (eventList[i].id != UNUSED)
checkEvent(&eventList[i]);
}
}
It’s about collaboration,customer, code, and product!
thanks:lumaxart
http://www.freestockphotos.biz/license.php?id=9749

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The Public First Scrum Class
(May 2003)
29

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0
100000
200000
300000
400000
Year
2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
Certified Scrum Masters
30

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0
100,000
200,000
300,000
400,000
Year
2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
Certiﬁed Scrum Developers Certiﬁed Scrum Masters
Certified Scrum Students
31

32
http://www.deviantart.com/art/Micro-manage-134602454

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What is Scrum?
33
Scrum exposes every inadequacy or
dysfunction within an organization’s
product and system development
practices. The intention of Scrum is to
make them transparent so the
organization can fix them.
From an interview with Ken Schwaber on agilecollab - http://www.agilecollab.com/interview-with-ken-schwaber
Ken Schwaber

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Like in the 80s! Short Cycle
Improvement
34

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Except without the Difficult
Improvement Part
35
ACT

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38

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39

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40
Not long after graduating
college, I joined an office product
company and started selling
copiers. I loved what i did.
James Murphy

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41
I had no flight
experience…, but I was
going to fly jets.
James Murphy

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42
Just two years after signing up, I was not only
flying, I was flying the supersonic F-15 Eagle

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43

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44
Pilots were
“Task Saturated”
Honest reflection
and analysis

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45
The Debrief outcome, gives the
refuel job to the boom operator, and
a rest for the pilot.

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What are We Supposed to Do?
46
The intention of Scrum is to make
them [your problems] transparent
so the organization can fix them.
Ken Schwaber

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How are we doing?
47

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Many think they’re doing great
48
In Company A 32% of the engineers said
they were in the top 5% of skill and quality
of work in the company. That seemed
outrageous until you go to Company B,
where 42% said they were in the top 5%.
So much for being lonely at the top.
Everybody tends to think that they are at
the top much more than they really are.
From David Dunning via Smart Planet
bit.ly/we-think-we-are-smart

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40% think they’re in the
top 5%
!
87.5% of them are wrong!
49

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50

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51

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10 Year Agile Celebration
52

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53
What do we, as
member of the
agile
community
need to fix?

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54

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We believe the agile
community must:
#1 Demand technical excellence
#2 Promote Individual [Change] and
Lead Organizational Change

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Remember what Ken Said?
56
"The intention of Scrum is to make
them [the problems] transparent so the
organization can fix them."
Ken Schwaber
Unfortunately, many organizations
change Scrum to accommodate the
inadequacies or dysfunctions instead
of solving them.

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Everything is Going Smoothly
57
Iteration 1 Iteration 2 Iteration 3 Iteration 4 Hardening

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ile 2014
58
Thank you: Hubert Stoffels, from Pittsburgh, USA '''Title:''' Jonathan's Run Falls
'''Description:''' http://commons.wikimedia.org/wiki/File:Jonathan%27s_Run_Falls.jpg
La, la la.
I’m lookin’
for bugs

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59Thanks to Yorian, Picture of a waterfall nearby Flam, Norway http://
commons.wikimedia.org/wiki/File:Waterfall_in_Norway.jpg
HELLLLP!

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What Happens We Save Test Until the End?
60
Iteration 1 Iteration 2 Iteration 3 Iteration 4 Hardening
Test and Fix
Test and Fix Test and Fix
Test and Fix
Test and FixTest and Fix

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Do Your Work Degrade into a Fire Fight?
61
Why Does ThisHappen??

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62

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63

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64
Hacking in newfeatures, chasing andmanaging bugs isnot TechnicalExcellence

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What’s the Problem?
65
from: Scrum with XP and Beyond
The biggest problem worldwide for
Scrum teams is getting shippable code
at the end of every sprint.
Jeff Sutherland

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66
The cadence of developmentchanges with Scrum
Are you changing the how you
engineer your products?

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The Marriage of Scrum and XP
67

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So Far the Marriage is Unequal
68
CertifiedScrum
M
asters
T
y
0
100,000
200,000
300,000
400,000
Year
2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
Certiﬁed Scrum Developers Certiﬁed Scrum Masters
54509
333820
Does this mean it takes six
CSMs to master one CSD?

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- A Brief Debrief -
Current Development Practice
in Industry
As viewed from the pre-
training surveys I use to
better understand
attendee backgrounds
69

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70

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71
How do you test your code?

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May 7 11:42:14: --- last message repeated 4 times ---
May 7 12:08:58 Cowboy kernel[0]: hibernate image path: /var/vm/sleepimage
May 7 12:08:58 Cowboy kernel[0]: sizeof(IOHibernateImageHeader) == 512
May 7 12:08:58 Cowboy kernel[0]: Opened file /var/vm/sleepimage, size 8589934592, partition base 0x0, maxio 400000 ssd 1
May 7 12:08:58 Cowboy kernel[0]: hibernate image major 14, minor 0, blocksize 512, pollers 5
May 7 12:08:58 Cowboy kernel[0]: hibernate_alloc_pages flags 00000000, gobbling 0 pages
May 7 12:08:58 Cowboy kernel[0]: hibernate_setup(0) took 0 ms
May 7 12:09:01 Cowboy kernel[0]: en1: BSSID changed to 00:40:96:a1:33:c9
May 7 12:09:01 Cowboy kernel[0]: wlEvent: en1 en1 Link DOWN
May 7 12:09:01 Cowboy kernel[0]: AirPort: Link Down on en1. Reason 8 (Disassociated because station leaving).
May 7 12:09:01 Cowboy kernel[0]:
May 7 12:09:37 Cowboy kernel[0]: hibernate_page_list_setall start 0xffffff80d4cff000, 0xffffff80d4f98000
May 7 12:09:37 Cowboy kernel[0]: hibernate_page_list_setall time: 415 ms
May 7 12:09:37 Cowboy kernel[0]: pages 2040801, wire 338507, act 950045, inact 182445, spec 36, zf 113125, throt 0, could discard act 169869 inact 207719
purgeable 38826 spec 40229
May 7 12:09:37 Cowboy kernel[0]: hibernate_page_list_setall found pageCount 1584158
May 7 12:09:37 Cowboy kernel[0]: IOHibernatePollerOpen, ml_get_interrupts_enabled 0
May 7 12:09:37 Cowboy kernel[0]: IOHibernatePollerOpen(0)
May 7 12:09:37 Cowboy kernel[0]: writing 1583874 pages
May 7 12:09:37 Cowboy kernel[0]: encryptStart 4f820
May 7 12:09:37 Cowboy kernel[0]: encryptEnd 108b02c0
May 7 12:09:37 Cowboy kernel[0]: image1Size 474682880, encryptStart1 4f820, End1 108b02c0
May 7 12:09:37 Cowboy kernel[0]: encryptStart 1c4b1600
May 7 12:09:37 Cowboy kernel[0]: encryptEnd b7957b30
May 7 12:09:37 Cowboy kernel[0]: PMStats: Hibernate write took 35189 ms
May 7 12:09:37 Cowboy kernel[0]: all time: 35189 ms, comp bytes: 6487916544 time: 6366 ms 971 Mb/s, crypt bytes: 2882564048 time: 4618 ms 595 Mb/s,
May 7 12:09:37 Cowboy kernel[0]: image 3080027136, uncompressed 6487916544 (535388), compressed 3068648576 (47%), sum1 ec64ffd2, sum2 571d97a2
May 7 12:09:37 Cowboy kernel[0]: wired_pages_encrypted 224499, wired_pages_clear 113814, dirty_pages_encrypted 1245651
May 7 12:09:37 Cowboy kernel[0]: hibernate_write_image done(0)
May 7 12:09:37 Cowboy kernel[0]: sleep
May 7 14:06:05 Cowboy kernel[0]: Wake reason: EC.LidOpen (User)
May 7 14:06:05 Cowboy kernel[0]: en1: 802.11d country code set to 'X0'.
May 7 14:06:05 Cowboy kernel[0]: en1: Supported channels 1 2 3 4 5 6 7 8 9 10 11 36 40 44 48 52 56 60 64 100 104 108 112 116 120 124 128 132 136 140 149 153
157 161 165
May 7 14:06:06 Cowboy kernel[0]: Sound assertion "0 == fAudioEngineArray" failed in AppleHDADriver at line 3163 goto Exit
May 7 14:06:08 Cowboy kernel[0]: Previous Sleep Cause: 5
May 7 14:06:08 Cowboy kernel[0]: MacAuthEvent en1 Auth result for: 00:40:96:a0:63:95 MAC AUTH succeeded
May 7 14:06:08 Cowboy kernel[0]: wlEvent: en1 en1 Link UP
May 7 14:06:08 Cowboy kernel[0]: AirPort: Link Up on en1
May 7 14:06:08 Cowboy kernel[0]: en1: BSSID changed to 00:40:96:a0:63:95
72

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76

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77
Congratulations!!!
You are using state of art
practices from 1979

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78
Debug-laterProgramming

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The Physics of Debug Later
Programming (DLP)
• As Td increases, Tfind increases dramatically
• Tfix is usually short, but can increase with Td
http://www.renaissancesoftware.net/blog/archives/16
79
Bug discoveryMistake made
(bug injection)
Bug found Bug fixed
Td Tfind T fix
Time

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A Bug’s Life
80
From http://www.softwaretestinghelp.com/bug-life-cycle/

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81
Your program will have
bugs. And they will
surprise you when you
find them.

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Zune 30G
82
Decem
ber31,2008

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83
BOOL ConvertDays(UINT32 days, SYSTEMTIME* lpTime)

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84
One That Got Away
static void SetYearAndDayOfYear(RtcTime* time)
{
int days = time->daysSince1980;
int year = STARTING_YEAR;
while (days > 365)
{
if (IsLeapYear(year))
{
if (days > 366)
{
days -= 366;
year += 1;
}
}
else
{
days -= 365;
year += 1;
}
}
!
time->dayOfYear = days;
time->year = year;
}

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85
This Test Could Have Prevented it
TEST(Rtc, check20081231)
{
days = daysSince1980(2008, 366);
CHECK(ConvertDays(days, &time));
assertDate(WED, 2008, 12, 31);
}
!

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86
Where do the
bugs come from?

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87

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88

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Really, It’s Not Our Fault?
89
James D. Murphy
We put them there

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This Work Flow is Designed to Allow
Defects
90
Development
Test
Defects

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A Bug’s Life
91
From http://www.softwaretestinghelp.com/bug-life-cycle/

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Edsger Dijkstra
If you want more effective
programmers, you will discover
that they should not waste their
time debugging, they should not
introduce the bugs to start with.
92

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We tend to do what we know
People do what they can conceive of,
but sometimes there are better solutions,
or considerations and risks they never
knew were out there. They don’t take a
solution they don’t know about.
93

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I’ve got 10 years
experience!
94
1 year 1 year 1 year 1 year 1 year
1 year 1 year 1 year 1 year 1 year

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It is almost impossible for an individual left to their
own devices to get self-assessment right. The worth of
one’s ideas runs through other people. That is, workers
should pay attention to what other workers are doing.
You can watch other people to benchmark how they
handle the same sorts of tasks or situations. Seek out
feedback from other workers or managers.
95

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96
Kent Beck Ron Jeffries
Ward Cunningham Martin Fowler

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eHarmony Match
97

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XP Identifies Shared Values
and Defines the Technical Practices
Needed for Growing Computer Software
98

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99
Quality is important Focus on it every day
Testing is good Test all the time
Reviews are good Review all the time
Customer input is good
Talk to your customer
every day
Planning is important
Keep the plan alive, plan to
replan

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Programming (DLP)
100
(bug injection)
Td Tﬁnd T ﬁx
Time

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101Thanks to Yorian, Picture of a waterfall nearby Flam, Norway http://
commons.wikimedia.org/wiki/File:Waterfall_in_Norway.jpg
HELLLLP!

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Edsger Dijkstra
If you want more effective
programmers, you will discover
that they should not waste their
time debugging, they should not
introduce the bugs to start with.
102

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• Write a test
• Watch it fail
• Make it pass
• Refactor (improve)
• Repeat until done
T
D
D

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devconfu, Nov 2013
Riga, Latvia
www.renaissancesoftware.net
james@renaissancesoftware.net

All Rights Reserved. Test Driven Development
www.renaissancesoftware.net
james@renaissancesoftware.net

All Rights Reserved. For use by training attendees.
If test moved upstream, could we get
working features to flow?
104

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Development and Test are a Continuum
Preventing Defects
105
Development
Test

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The Physics of Test Driven
Development
• When Td approaches zero, Tfind approaches zero
• In many cases, bugs are not around long enough to be considered
bugs.
• See: http://www.renaissancesoftware.net/blog/archives/16
106
Mistake
discovery
Mistake
made
Root cause
found
Mistake fixed
T d Tfind T fix
Time

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107
TDD is FUN!
TDD is a challenge.
It’s hard to learn.

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108
A Complex system that
works is invariably
found to have evolved
from a simple system
that worked.

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109
Unit Tests are Critical!
Is your team doing TDD?
Does your team create
unit tests?
Writing tests after is
not so fun, but

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System Level Tests Cannot be
Thorough
• How many sub-system tests are needed?
110
10
states
10
states
10
states
5 interactions
5 interactions
5 interactions
Tests

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TDD unit tests can be thorough
• How many unit tests are needed?
111
10
states
10
states
10
states
5 interactions
5 interactions
5 interactions
Tests Tests

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112
Solid
foundation
Wired properly and
meets customer needs
Looks and
feels right

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113

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114
Tests Must be Automated

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test
Assume Test Effort is
Proportional to
Development Effort
dev
Iterations
Effort
5
10
15
20
25

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If a system is working,
leave it alone. Don't
change anything.
Systems don’t
appreciate being fiddled
and diddled with.
• 25% of all defects are
introduced while
changing and ﬁxing code. 
[R.B Grady, Software Process Improvement]

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117
System Antics
System - something setup to attain a goal
Antics - amusing, frivolous, or eccentric
behavior

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118
Systems

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119
System Antics

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120
Because systems actup -- we have to bevery careful.

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test
Manual Test is
Unsustainable
Effort
Iterations
Unsustainable growth
dev
5
10
15
20
25

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Risk Accumulates in
the Untested Code Gap
Effort
Iterations
dev
5
10
15
20
25 Untested Code Gap
test

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My Take Away
123
Keep the cost of retest low
Keep the system
running
Tests Must be Automated

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Try to Reframe the Problem
124
We can’t afford to write automated tests,it takes away from adding new features
We can’t afford to not automate tests,
the manual retest time takes away
from adding new features

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We believe the agile
community must:
#1 Demand technical excellence
#2 Promote Individual [Change] and Lead
Organizational Change

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126
TechnicalExcellence isn’tJust Passing
Tests

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127
Why does code
structure matter?

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128
The Two Values of Software

129
Defined
“Refactoring is the process of changing a software
system in such a way that it does not alter the external
behavior of the code yet improves its internal
structure.” [REF]
!
!
• Refactoring Debt
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Refactoring Goal
• “Clean code that works”
– Ron Jeffries
130Technical Excellence
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How?
• Remove duplication
• Fix bad names
– J.B. Rainsberger
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OOP, Munich 2015
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Let us change our
traditional attitude to the
construction of programs.
Instead of imagining that
our main task is to
instruct a computer what to
do, let us concentrate rather
on explaining to human
beings what we want a
computer to do.
Donald Knuth Says
132

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Really, It’s Not Our Fault?
133
James D. Murphy
How are we doingat that one?

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Spaghetti Slide
134

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135

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136

Martin Fowler Says
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Any fool can write code
that the compiler
understands, but it takes
real skill to write code
other programmers can
understand.
From “Refactoring - Improving the Design of Existing Code

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138
Code ‘Badness’ Over time
0
25
50
75
100
CodeBadness
Time

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139
0
25
50
75
100
CodeBadness
Time

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Developers Need to Know and Practice
Refactoring’s Three Critical Skills
140
Recognize what is wrong, fix it!
Keep the code working the whole time!

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141
If a system is working,
leave it alone. Don't
change anything
Systems don’t
appreciate being fiddled
and diddled with

Humpty Dumpty from The Book of Knowledge,
p. 968, Vol. III, The Grolier Society, New York, 1911.
Code with
design problem
Envisioned
design
Improved
design that works
Take it apart, put it back together.
The system is broken during redesign effort.
Broken
Debug
Rework
Unpredictable
Unhappy
Refactor to the better design.
Test are always passing.
The system is never broken.
Refactoring vs.
Humpty Dumpty Redesign
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Automated Tests Make Refactoring Safer
143
Test
Test
Test
Test
Test
Test
Test
Test
Rename
Extract
Move
Extract
Extract
Replace switch
Encapsulate
Move

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144
Sustain Low Code ‘Badness’ Over time
0
25
50
75
100
CodeBadness
Time

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Spaghetti Slide
145

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146
0
25
50
75
100
CodeBadness
Time

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147
Why does code
structure matter?

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148
The Lawyers are
Coming

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149

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150

151
"We've demonstrated how as little as a single bit
flip can cause the driver to lose control of the
engine speed in real cars due to software
malfunction that is not reliably detected by any
fail-safe,"
- Michael Barr, CTO, co-founder of Barr Group
http://www.eetimes.com/document.asp?doc_id=1319903

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Stack overflow and software bugs led to memory
corruption, he said. And it turns out that the crux of
the issue was these memory corruptions, which acted
"like ricocheting bullets."
• “Kitchen Sink” (a.k.a. do it all) task
• Responsible for closed loop control and failsafes

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153
You don’t want to create
this website

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154
Why doesn’t your team use
TDD and Refactoring and the
other technical practices of
Agile?

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We’re different!
155

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We can’t use TDD
and Refactoring!
156

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Everything is fine.
157

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REALLY!
158

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pay no attention
to that fire over
there
159

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REALLY!
160

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We’re BUSY!
161
ACT

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What Slows You Down?
162

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90%
done
163

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164

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1
165

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We’re different!
166

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167
Embedded software
is special

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168
Web service software
is special

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169
Health Insurance
software
is special

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170
Design automation
is special

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171
Financial Software
is special

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172
YOU
are special

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173
It just does not
matter.

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What are We Supposed to Do?
174
The intention of Scrum is to make
them [your problems] transparent
so the organization can fix them.
Ken Schwaber

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What is the biggest problem of getting
there?
175
from: Scrum with XP and Beyond
The biggest problem worldwide for
Scrum teams is getting shippable code
at the end of every sprint.

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176
What is in your
way?

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`
177
My Boss won’t let me

178
Development
Organizations want
fast development.

179
I don’t have time for
all this extra stuff!!

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Programming (DLP)
180
(bug injection)
Td Tﬁnd T ﬁx
Time

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181

182
Michael Dubakov
Speed in SW Development
http://bit.ly/sw-dev-speed
Slow workstation
Development
Speed
Skills
Waste and
Non-value
added activity
Mentor other
people
Orange
Fridays
New people
More
Development
teams
Conferences
People who
learn things
system
complexity
Technical
debt
Cowboy
coding
Deadlines
Refactoring
Unclear
requirements
Re-work
Bad UX - Dev
transition
Focused
Work
IM/Skype
Open
Space
Emergency
rotation
people rotations
between teams
UX meetings
Unstable /
slow Tests
More work
coordination
Multi-tasking
Large WIP
Prototypes
Good Specs
Domain
Knowledge
Daily
Meetings
Sport at work
Meetings
Board
meetings
Passion
Bugs
Wait states
Good Features
Ranking Model
Do right things
HR interviews
Disciplined
process
Work
experience
Work / Life
balance
Sport /
Hobbies
outside work
Fast feedback
Short term
boost
Good It depends Bad
Increasing eﬀect Decreasing eﬀect
Overtime
Cooperative
testing
http://bit.ly/sw-dev-speed

183
Development
Speed
Skills
system
complexity

184
Development
Speed
Technical
debt
Deadlines Short term
boost
Overtime

185
Development
Speed
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
boost
Overtime

186
Development
Speed
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
boost
Overtime
Development
Speed
Focused
Work

187
Development
Speed
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Focused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Short term
boost
Overtime

188
Development
Speed
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Focused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Short term
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Unclear
requirements
Re-workFocused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Bugs
Do right things
Short term
boost
Overtime

189
Development
Speed
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Focused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Short term
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Unclear
requirements
Re-workFocused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Bugs
Do right things
Short term
boost
Overtime
Slow workstation
Development
Speed

190
Development
Speed
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Focused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Short term
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Unclear
requirements
Re-workFocused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Bugs
Do right things
Short term
boost
Overtime
Slow workstation
Development
Speed
Development
Speed
More
Development
teams

191
Development
Speed
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Focused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Short term
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Unclear
requirements
Re-workFocused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Bugs
Do right things
Short term
boost
Overtime
Slow workstation
Development
Speed
Development
Speed
Waste and
Non-value
added activity
Mentor other
people
New people
More
Development
teams
More work
coordination
Meetings
HR interviews

192
Development
Speed
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Focused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Short term
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Unclear
requirements
Re-workFocused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Bugs
Do right things
Short term
boost
Overtime
Slow workstation
Development
Speed
Development
Speed
Waste and
Non-value
added activity
Mentor other
people
New people
More
Development
teams
More work
coordination
Meetings
HR interviews

193
Of course we don’thave time!!

Development
Speed
Skills
Conferences
People who
learn things
Focused
Work
Domain
Knowledge
Passion
Work
experience
Work / Life
balance
Development
Speed
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Focused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Short term
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Unclear
requirements
Re-workFocused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Bugs
Do right things
Short term
boost
Overtime
Slow workstation
Development
Speed
Development
Speed
Waste and
Non-value
added activity
Mentor other
people
New people
More
Development
teams
More work
coordination
Meetings
HR interviews

Development
Speed
Skills
Conferences
People who
learn things
Focused
Work
Domain
Knowledge
Passion
Work
experience
Work / Life
balance

196
Why are deadlines,
overtime, and increasing
technical debt such a
popular practice in
development?
Development
Speed
system
complexity
Technical
debt
boost
Overtime

197
Development
Speed
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Focused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Short term
boost
Overtime
Development
Speed
system
complexity
Technical
debt
Deadlines
Unclear
requirements
Re-workFocused
Work
Emergency
rotation
people rotations
between teams
Multi-tasking
Large WIP
Bugs
Do right things
Short term
boost
Overtime
Slow workstation
Development
Speed
Development
Speed
Waste and
Non-value
added activity
Mentor other
people
New people
More
Development
teams
More work
coordination
Meetings
HR interviews
Why are the destructive practices
so much more prevalent?

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People do what they can conceive of,
but sometimes there are better solutions,
or considerations and risks they never
knew were out there. They don’t take a
solution they don’t know about.
198

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Managers, Leaders and Coaches
TODO
199
Make sure your team
knows state of the art
practices
Support
learning,
problem solving,
and continuous
improvement
Make sure your
organization
knows why they
are important

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Yeah but I’m an engineer
200

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201
People are generally
doing the best they know
Often, people don’t know
what they don’t know

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Developers
TODO
202
Become an
expert in
your craft
Become an
advisor to your
organization
learn and try
new things
Build Trust -
Make your
Work Visible
Work with
others

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203
Beware of limits

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Scrum Masters
TODO
204
Encourage your
people to be
problem solvers Not dogma
followers
Remember: there are no scrum slaves

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Managers
TODO:
205
Grow great
teams
Stop
Motivating
Your Team

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Motivation
206
Motivating an individual or
a team is hard
While demotivating them is
really easy!

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Avoid De-motivators
207
Unrealistic
deadlines
Encouraging
poor quality work
Punishing
the truth
Lack of trust Stretch goals

OOP, Munich 2015
www.wingman-sw.com
Oop@wingman-sw.com

Motivators
208
Problem
solving
Knowing
the Vision
Knowing
why it is
important
Trust
Mutual respect

OOP, Munich 2015
www.wingman-sw.com
Oop@wingman-sw.com

I Tried to Avoid
Computers
209

210
Thanks @tech_faq
!
https://twitter.com/tech_faq/status/386781833343414272/photo/1

OOP, Munich 2015
www.wingman-sw.com
Oop@wingman-sw.com

211
People will pay me
for this?!!

OOP, Munich 2015
www.wingman-sw.com
Oop@wingman-sw.com

212
Putting out fires in the untested
code gap is not technical
excellence
test
Effort
dev
5
10
15
20
25 Untested Code Gap

OOP, Munich 2015
www.wingman-sw.com
Oop@wingman-sw.com

All Rights Reserved @jwgrenning. The End
__EVENT__ www.wingman-sw.com
james@wingman-sw.com
Copyright © 2008-20XX James W. Grenning

http://commons.wikimedia.org/wiki/File:Abies_nordmanniana_PAN_2.jpg

OOP, Munich 2015
www.wingman-sw.com
Oop@wingman-sw.com

Demand Technical Excellence
214
Talk to me on Twitter
@jwgrenning!
!
Find my book at!
http://wingman-sw.com/tddec
!
Find me on linkedin.com
http://www.linkedin.com/in/jwgrenning
Please remind me how we met.
!
http://www.wingman-sw.com
http://www.wingman-sw.com/blog

Technical Excellence - OOP Munich 2015

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