© 2006 IBM Corporation

Software Engineering in the Real World

Team Based Software Development

Paul GibsonDevelopment Operations Manager

IBM Software Group Development Laboratory at Hursley

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation2

Objectives

Understand some of the issues of real world software development projects.

Identify practical responses to these issues.

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation3

Software Project Types

Market Product / Solutions (Approx 1/3) Multi-Customer Multiple Supported Versions Conflicting Requirements

Bespoke Solution (Approx 2/3) Single Customer Requirements negotiable

Personal Requirements understood

Tea

m S

ize

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation4

Software Development Environment

The Dream All the time you need Clear and Stable Requirements A clear foundation on which to build Waterfall or Iterative Development Process All the people you need

Real Life Market & Customer Time Pressure Changing Requirements Dependencies being developed in parallel Overlapping Development Phases Limited Resources & Conflicting Needs

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation5

You start programming – I’ll find out what they want!

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation6

As Team Size Grows above 15 to 20

Problems arise Control Communication

Responses Process & Ownership Organisation & Team Structures Architecture Change Control Code Base Control Progress Tracking

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation7

Control & Communication IssuesDecision Making

Who has the Authority?

Who understands the implications and cost?

Who has to implement?

Who is accountable?

Multiple Teams with Multiple Goals Different Functions (Planning, Design, Develop, Test, Service)

Different Locations & Countries

Different Companies (Co-operation & Competition)

Access to Key Information & Changes to Schedules

Requirements & Specifications

Architecture & Design

Interfaces

Project & Dependencies Status

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation8

Need to Agree….

Organisation Style

Ownership

Aligned Goals

Team Responsibilities

Project Management Process

Communication Processes & Frequency

Education & Skills

HR Policies

Team Building Actions

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation9

Process vs Ownership

Objective

defined process

measurable progress

traceability to specs

documented work

repeatable work

organization focused

compliance praised

High Ceremony

Cognitive

problem-solving

meaningful results

relevance to mission

peer communication

effective work

people focused

technical insight praised

Low Ceremony

Bureaucracy vs Chaos

From James Bach : www.satisfice.com

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation10

Organisation & Teams

As team size grows optimal structure changes

Project > Functional > Matrix > Large Project

Direct Line Management for Ownership

Functional Organisation for Efficiency

Multi-Disciplinary Teams for Decisions

Considerations

Minimise hand offsOrganise for Leaders

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation11

Architecture

As team & project size grows optimal architecture changes

Small, Simple, Uncontrolled Comprehensive, Complex, Controlled

Modularity and Encapsulation become vital

Rigorous Control of all Interfaces

Architecture Board

Considerations

Effective Communication is essential

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation12

Change Control Must have Short Cycle Time ( Iterative )

Control Specification and Product Growth

Database Control of Architecture & Design

All deliverable function raised as Design Change Requests

Further changes tightly controlled

Two Sources of Potential Change

1. Request for Additional Function

2. Implementation or testing uncovers design error

3. (Developer’s “Good Ideas”)

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation13

Change Control Process Formal Request for Change

Review by Project Team & Design Team for

Cost of AnalysisIf cost of analysis is acceptable then

Cost of ImplementationRisk ( Mitigated or Added )UrgencyStrategic ValidityReturn or ValueCustomer Impact

Request formally Committed, Rejected or Deferred

Decision clearly communicated to all

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation14

Codebase Control Challenges

Large project may have 30,000 components

Individual changes potentially effect many components

Single codebase may support multiple releases and multiple platforms in the market

Enable Maximum Reuse

Components can have multiple owners

Multiple Concurrent Development and Service Streams

Delivered by Library Control System / Configuration Management

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation15

Library System Requirements

Base

Feature 1

Feature 2

Feature 3

Fixes required to all streams

Multiple Concurrent Feature and Platform Development

Merge Features with

the Base

Features have PreReqs

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation16

Library System Requirements

Release 1

Release 2

Release 3

Release 4

Fixes Required by Customers

X End of Life

Multiple Concurrent Release Support

Fixes must be merged back to earlier or later releases if code

is not common

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation17

Codebase ControlEnforced by Library Management

All necessary code changes formally tracked and linked to causes / problems

Late & development initiated changes tightly controlled

Multiple Ownership Effectively Managed

Sources of Potential Change

New Requirement Market, Customer, Executive, Development, Test

New Understanding from Iterative Implementation

Defect Discovered Inspections or Analysis detect error Testing detects error In this feature/component, dependent feature/component/product

Field Problem This release or later release

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation18

Codebase Control increases with time

Less restrictive in changes during early code development(Trust everyone)

Rigorously review of all requests for change in later stages (Trust no-one)

Rigorous review for

Potential Customer ImpactRisk of failureRisk of further injectionWorkarounds

Decide what to fix & what to FIN (Fix in Next)

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation19

Progress Tracking Owned by Project Leader

Formal Commitment Tracking

Estimation is critical - based on track records

Include all functional areas

Business, Marketing, Development, Test, Production, Service

Monthly risk assessments

Earned Value Tracking

Rolled up to project level

Communicated, Published, Shared

Metrics & Process Improvement

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation20

SummaryTeam Based Development Issues Identified

Control

Communications

Strategies for dealing with the Issues

Process & Ownership

Organisation & Team Structures

Effective Architectures

Change Control

Code Base Control

Progress Tracking

© 2006 IBM Corporation

Any Questions?

IBM Software Group

Team based Software Development – Jan 2006 © 2006 IBM Corporation22

References

www.satisfice.com

James Bach – Thought provoking views on S/W Development

www.american.edu/academic.depts/ksb/mogit/carmel.html

Erran Carmel - Research on Global Software Teams

www.swebok.org

IEEE Software Engineering Body of Knowledge

www.sei.cmu.edu

Software Engineering Institute

www.methods-tools.com

Software Methods & Tools

www.research.ibm.com/softeng/odc/odc.htm

Orthogonal Defect Classification

www.bcs.org.uk/index.html

The BCS

www.martinfowler.com/articles/newMethodology.html#N400062

Agile Methodologies

www.extremeprogramming.org/

Extreme Programming