Agile development

Question 1

what is agile SW development

Answer 1

put software being developed first
acknowledge that use requirements change
respond to changing needs quickly
advocates for regular software releases - users respond to these releases

Question 2

Agile manifesto key points

Answer 2

individuals and interactions over process and tools
working software over hella documentation
customer collaboration over contract negotiation
responding to change vs following a plan

Question 3

12 agile principles

Answer 3

satisfy the customer
give workers the support they need and trust them
technical excellence
welcome changing requirements
face=to=face conversation
simplicity
self-organizing teams
working software
deliver frequently
business peolpe and devs work together
maintain constant pace
reflect on how to be more effective and adjust behavior

Question 4

Explain the 80/20 rule (Pareto’s Law)

Answer 4

80% of results come from 20% of your effor and focus on the important 20%

Question 5

how to deal with requirements in agile

Answer 5

capture requirements at a high level and on a piecemeal basis
- just in time for each feature to be developed
-the minimum to enable development and testing
understand enough to determine the scope and for high level budget estimates
captured in collaborative workshops so taht all team members understand the requirements - allows everyone to contribute

Question 6

what are user stories

Answer 6

represent each user requirement as a user story
- more light weight and simpler than use cases
simple statement about what the user wants to do with a feature
business language and understandable to everyone

Question 7

form of user stories

Answer 7

As a (user role)
I want to (goal)
so i can (reason)

focus on who what and why NOT HOW

Question 8

How long should requirements (tasks) take

Answer 8

less than 16 hours

preferably 8 hours so progress can be measured daily

Question 9

three basic steps in agile life cycle

Answer 9

analyse
develop
test

Question 10

benefits of agile approach

Answer 10

reduced risk
increased value
more flexibility
better cost management

Question 11

What does DONE mean in agile

Answer 11

shippable

• unit tests passed
• code reviewed
• acceptance criteria passed
• non-functional requirements met
• functional tests passed
• product owner accepts user story

Question 12

two main classes of prototypes

Answer 12

true prototype - test implementation to understand a problem before it is implemented for real
tracer bullets - intended to gradually turn into the final solution

Question 13

continuous integration

Answer 13

continuously integrate changes - ensure that modules will fit together - product continues to work with all the changes
ensure that problems or regressions are caught early on

Question 14

nightly builds

Answer 14

software should be rebuilt from scratch daily
and the result of the build should be an installable product image
build should include as many automated tests as possible to catch integration problems early
- if tests/build fail - fix first thing
- dont let anyone integrate changes after build succeeds again
- risk of bad changes accumulating

Question 15

what is pair programming

Answer 15

programmers work in pairs, sit together to write every line of code
- 2 coders and 1 computer
- 1 person at keyboard and one suporting
- pairs created dynamically
egoless development

Question 16

Advantages of pair programming

Answer 16

informal review process
common ownership of code
share responsibility
spread knowledge
motivates refactoring

Question 17

how does pair programming affect productivity

Answer 17

similar productivity to two devs working independently - fewer false starts and less rework, less debugging
can help train inexperienced devs
pair for complex tasks

Question 18

challenges of pair programming

Answer 18

scheduling
constant communication
different skill levels
power dynamics
no time for self 
rotation lead to context switching

Question 19

challenge of code review

Answer 19

sloppy or superficial reviews
over reliance of developer on reviewer to catch minor issues
sunk cost - reluctant to tell devs to change something that they thought was already done

Question 20

test driven development

Answer 20

programming technique that ensure that code is thoroughly unit tested
if a test fails - you know what is causing the problem and what to fix
increased confidence that system meets requirements

Question 21

side effect of TDD

Answer 21

achieve 100% coverage test - every single line of code is tested
resulting tests are working examples for invoking the code - provides working spec for the code

Question 22

how is testing done in agile

Answer 22

testing is integrated throughout the life cycle
does not have separate test phase
devs write automated repeatable unit tests - testing done as part of the build
these actions keep the software in a releasable condition throughout development

Question 23

What is test first development

Answer 23

writing tests before code clarifies requirements that need to be implemented
tests are programs rather than data - executed automatically like Junit

Question 24

what is the customer’s involvement in testing

Answer 24

help develop acceptance tests for the stories implemented int the next release of the system
all new code is therefore validated to ensure that it is what the customer needs
customers have limited time available:
- cannot work full-time with dev team
- may feel that providing requirements was enough
- may be reluctant to get involved in the testing phase

Question 25

Test first development process

Answer 25

quickly add test for new feature - just enough for code to fail
run tests
update the functional code to make it pass new tests
run tests again
once tests are passed, start over

Question 26

What is test driven development

Answer 26

TDD = TFD + refactoring
write tests before functional code
small steps and a small bit of code at a time
devs refuse to write new function unless there is a test that fails because the function isn’t present

Question 27

TDD cycle steps

Answer 27

Think, test, code, refactor (code and refactor loop)

Question 28

The rules of test driven development

Answer 28

write new code only when an automated test fails
eliminate any duplication
-

Question 29

what makes good unit tests

Answer 29

run fast
run in isolation
use data to make them easy to read and understand
use real data when they need to - copies of production data
represent one step towards overall goal

Question 30

what is refactoring

Answer 30

systematic process of improving code without creating new functionality that can transform a mess into clean code and simple design

Question 31

benefits of refactoring code

Answer 31

improves design of the software
makes software easier to understand
helps find bugs
help you to program faster

Question 32

categories of refactoring

Answer 32

composing methods
moving features between objects
organizing data
simplifying conditional expressions
making method calls simpler
dealing with generalization