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Essence: A Common Ground for Flexible Methods

Ed Seidewitz

• Embody essential concepts in a kernel.• Work with methods in an agile way that are as close to

practitioners’ practice as possible.• Focus on the things that matter the most.• Focus on helping the least experienced developers over helping

more experienced developers.• Understand that the majority of practitioners are interested in…

– the use of methods, not their definition.– practice, not process or method engineering. – intuitive and concrete graphical syntax, not formal semantics.

Principles of Essence

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• “Foundation for Agile Creation and Enactment of Software Engineering Methods” (FACESEM) RFP issued June, 2011

• Essence – Kernel and Language for Software Engineering Methods submitted February 2013

• Essence 1.0 Finalization Task Force chartered March 2013• Essence 1.0 (beta) adopted May 2014

The Essence Specification

Method Architecture

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The Kernel is the common ground thus it includes essential elements of software engineering.

The Language is used to define methods, practices and the essential elements of the Kernel.

A practice is a repeatable approach to doing something with a specific purpose in mind.

A method is an enactable composition of practices.

The Kernel

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A stripped-down, lightweight set of definitions that captures the essence of effective, scalable software engineering in a practice independent way.

The Kernel is described using a small subset of the Language.

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Alphas: The things to work with

Activity Spaces: The things to do

Competencies: The abilities needed

Content of the Kernel

What is an alpha?

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• Alpha is an acronym for an Abstract-Level Progress Health Attribute.

• An essential element of the software engineering endeavor that is relevant to an assessment of the progress and health of the endeavor.

Software Engineering Kernel Alphas

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Alphas: Example

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Requirements

Description

What the software system must do to address the opportunity and satisfy the stakeholders.

It is important to discover what is needed from the software system, share this understanding among the stakeholders and the team members, and

use it to drive the development and testing of the new system.

Associations

scopes and constrains : Work

Software Engineering Kernel Activity Spaces

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Activity Spaces: Examples

Scrum Essentials PracticeActivity Space

Activity

Activity Predecessor Relationship

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Software Engineering Kernel Competencies

The Language

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The language provides three graphical views:1. Alphas and Their

States2. Sub-Alphas and Work

Products3. Activity Spaces and

Activities

The language is defined in five packages:1. Foundation2. Alpha and Work Product3. Activity Space and

Activity4. Competency5. User Defined Types

The Language: Small, Simple and Flexible

Competency

Alpha State

Activity Space <

invo

lves

targ

ets

>

Alpha

< h

asActivity

Work Productprogressed by >

prod

uces

/ upd

ates

>

organizes >

< describes

organizes >

< evidences

< results in

PatternResource

Can be added to anything

< require

s

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Language: Graphical Notation Examples

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Language – Textual Notation Example

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alpha Requirements { "What the software system must do to address the opportunity and satisfy the stakeholders." has {

state Conceived {"The need for a new system has been agreed.” checks {

item cli1 {"The initial set of stakeholders agrees that a system is to be produced."} item cli2 {"The stakeholders that will use and fund the new system are identified."} item cli3 {"The stakeholders agree on the purpose of the new system.”}item cli4 {"The expected value of the new system has been agreed."}

} } state Bounded {

"The theme and extent of the new system is clear." checks {

item cli1 {"Stakeholders involved in developing the new system are identified."} item cli2 {"It is clear what success is for the new system."} item cli3 {"The stakeholders have a shared understanding of the extent of the proposed solution."} item cli4 {"The way the requirements will be described is agreed upon.”}item cli5 {"The mechanisms for managing the requirements are in place."}

} }

…

Language: Semantic Framework

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Semantics: Determination of State using Check Points

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Practices

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Practices and methods are built on the language using the kernel.

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Documenting Practices

Tacit Practices

With Coaching

Explicit Practices

With Coaching

Background

Capability

Common Different

ExplicitPracticesNeeded

TacitPracticesSufficient

High

Low

A Practice Architecture

Mobile Application

DevelopmentMethod

Kernel

Core Banking Development

Method

Enterprise Integration

Method

Defect/Issue Tracking

Configuration Management

Defect/Issue Tracking

Configuration Management

Defect/Issue Tracking

Configuration ManagementCommonPractices

Waterfall Lifecycle Modern Lifecycle Modern Lifecycle

Architecture Centric Emerging Architecture

Emerging Architecture

Traditional Requirements User storiesUse Cases

Endeavor TypeSpecificPractices

Acceptance Test DrivenDevelopment

Acceptance Test DrivenDevelopment

Acceptance Test DrivenDevelopment

Improvement

Practice Composition: Base Practices

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Iterative Planning Practice

Iterative Assessment Practice

Agree on Iteration

Guide Team

IterationPlan

Evaluate Result

IterationAssessment

Practice Composition: Composite Practice

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Iterative Development

Agree on Iteration

Guide Team

IterationPlan

Evaluate Result

IterationAssessment

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Practice Explorer

The Practice Explorer shows Practice Workbench projects

The Essence Kernel project contains the elements defined in the OMG Essence specification

Alphas that represent the essential things to work with

Activity Spaces that represent the essential things to do

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ETextile, Guideline and Card views

When selecting an element in the Practice Explorer you can switch between different views

The ETextile Source view provides the main editor for authoring the practice using plain text and annotations

The Guideline Preview renders how the guideline will be presented in HTML

The Overview Card Preview renders the card presentation

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Scrum Essentials

The Scrum practice is created as a separate practice project in the Practice Workbench

The Scrum practice extends the Essence Kernel by providing more detailed guidance.

Drag and drop the relevant Alphas to extend from the Essence Kernel into the Scrum practice project

Drag and drop the relevant Activity Spaces to extend from the Essence Kernel into the Scrum practice project

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Scrum Roles

Scrum roles are represented as Patterns

Product Owner (Guideline Preview)

Product Owner (Card Preview)

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Scrum Sprint

Sprint is represented as a sub-alpha of Work

The Sprint has States with Checkpoints

The Sprint has associated the Work Product Sprint Backlog that contains the set of Product Backlog items selected for the Sprint, and the plan for delivering the product Increment

Sprint (Card Preview)

Sprint in Under Control State(Card Preview)

Under Control(State Card Preview)