Writing code 
that lasts. 
Rafael Dohms 
@rdohms 
photo: djandyw.com
Writing code 
you won’t hate tomorrow. 
Rafael Dohms 
@rdohms 
photo: djandyw.com
Let me 
introduce 
you to 
someone…
No Tests. 
shhh.. don’t tell Grumpy. 
Wrote his own framework. 
.. and used it. 
Used Singletons! 
.. and every other anti-pattern out there. 
500 line methods. 
… not even methods, they were functions
photo: Rob Allen (@akrabat)
REWRITE 
ALL THE CODE!
photo: Glyn Lowe Photoworks 
Real Developers, 
SHIP STUFF.
How do we find 
balance? 
photo: Kalexanderson
Code has an 
expiration date 
photo: CarbonNYC
Code is 
photo by: massdistraction 
perishable, it rots.
Code Evolves 
photo by: kevin dooley
Languages evolve. 
photo by: raneko
You evolve. 
photo by: Kaptain Kobold
Complexity 
kills 
Comprehension 
photo: osbornb
Bad Design 
photo: miskan
Bad specs
NIH 
photo by: John 'K' 
source: Urban dictionary
NIH 
| nɒt ɪnˈventɪd hɪə | 
Not Invented Here —The German art of humiliating any technology, 
agricultural product, or (medical) scientific work that has not been 
invented or produced in Germany, Switzerland, or Austria. 
photo by: John 'K' 
source: Urban dictionary
The Solution™ 
photo: Ian Sane
Improve code
make it easier to comprehend 
Improve code
make it easier to comprehend 
make it flexible 
Improve code
make it easier to comprehend 
make it flexible 
make it tested 
Improve code
make it easier to comprehend 
make it flexible 
make it tested 
Improve code 
make it easier to replace, refactor
make it easier to comprehend 
make it flexible 
make it tested 
Improve code 
make it easier to replace, refactor 
make it not exist
Testing 
photo by: jeffkrause
Good Design 
Concepts
SOLID 
Single Responsibility 
Open and Close 
Liskov substitution 
Interface Segregation 
Dependency Inversion 
photo by j_regan
photo by lofink 
STUPID 
Singleton 
Tight Coupling 
Untestability 
Premature Optimization 
Indescriptive Naming 
Duplication
photo by halloweenstock 
Design Patterns
Composer
PIE 
Proudly 
Invented 
Elsewhere
guzzle/guzzle 
HTTP client for RESTful API clients 
photo by j_regan
morrisonlevi/ardent 
A library of collections for PHP
Readability 
photo: Morgenland
paragraphs 
photo: Trossachs Photography
whitespace
Cape Town São Paulo 
R&D Team for MIH/Naspers
Object 
Calisthenics 
photo by: boston_public_library
Calisthenics 
/ˌkaləsˈTHeniks/ 
Calisthenics are a form of dynamic exercise consisting of a variety of 
simple, often rhythmical, movements, generally using minimal 
equipment or apparatus. 
photo by: boston_public_library
Its about perception, 
not rules or standards photo by: david_a_l
#1 
Only one 
indentation level 
per method. 
photo by: justinliew
#2 
Do not 
use else 
photo by: justinliew
#3 
Wrap primitive 
types, if they 
contain behavior 
photo by: justinliew
#4 
Only one 
-> per line 
photo by: justinliew
#5 
Do not 
abbreviate. 
photo by: justinliew
#6 
Keep your 
classes small. 
photo by: justinliew
#7 
Limit your 
instance variables 
to less then 5 
photo by: justinliew
#8 
Use first class 
collections 
photo by: justinliew
#9 
Use getters 
and setters. 
photo by: justinliew
#10 
Document 
your code. 
photo by: justinliew
Your turn.
Improve 
yourself!
Read lots of 
code!
Write simple 
code.
Try Object Calisthenics 
for a month.
Use someone 
else’s code.
Share bite size 
libraries.
Thank you. 
@rdohms 
https://joind.in/12734 
http://doh.ms 
http://slides.doh.ms 
please rate me!
http://l.doh.ms/oc-links 
Video recording 
Slides 
Books 
Resources on 
Object Calisthenics

Writing code you won't hate tomorrow