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End User Software Engineering

Mary ShawCarnegie Mellon University

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EUSE goes beyond EUP EUP includes “programming-like” activities,

such as programming, debugging, tailoring via parameters, simple scripting

EUSE goes beyond this … Design and composition of systems from elements Evolution, development, maintenance Deliberate process for creating software Expressiveness and understandability Sufficient dependability for current need Concern for system properties – usability,

dependability, security, privacy Note the process tension between

“opportunisim” and systematic planning

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EUs are not SEs EUs do not have rich and robust mental

models of their computing systems they fail to do backups, misunderstand storage

models, execute malware, and innocently engage in other risky behavior

EUSE is not “fixing the users” EUSE must be about developing ways for

EUs themselves to address traditional SE concerns

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Papers that addressed (some of) these issues

Brandt &al, Opportunistic Programming

Costabile &al, End Users as Unwitting Developers

Scaffidi &al, Topes for Validating and Reformatting Data

Stoitsev &al, EUD for Enterprise Process / Info Mgt

Wong &al, Patterns in Mashups

Umarji &al, Teaching SE to End-users

Coutaz, EUP and Intrinsic Complexity of …

Shani &al, SW Design / UML / Domain Specific Lang

Doerner &al, EUD: Challenges in SOA

Sestoft, Function Spreadsheets

Praehofer, EUP Environments in Automation Domain

El-Gayyar, User-oriented Web Services Composition

Brandt

Constabile

Scaffidi

Sestoft

Praehofer

El-Geyyar

Coutaz

Shani

Doerner

Stoitsev

Wong

Umarji

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Composition of systems from elements

Models for composition of elements Use patterns to guide mashups [Wong] Managing service compositions with many

component proprietors [Coutaz]

Package new capability as plugins or extensions for existing systems [Scaffidi, Stoitsev, Sestoff]

Finding resources Provide hierarchy of repositories from personal to

local to global [Scaffidi] Finding services [Doerner]

Scaffidi

Sestoft

Coutaz

Doerner

Stoitsev

Wong

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Models for composition of elements

Wong, Patterns in Mashups “Mashups” combine information from multiple web

sites in new ways Survey found several types: aggregation; alternate

UI or specialized use; personalization; focused view of data; real-time monitoring

Large comparative table shows differences Coutaz, EUP and Intrinsic Complexity of …

Model based on molecular chemistry shows richness of mixed physical-digital network artifacts

elements are digital or physical atoms composition is based on, e.g., valence and affinity

Proposal: Base composition of services on this model

Coutaz

Wong

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Packaging new capability as plug-ins, etc

Scaffidi &al, Topes to Validate, Reformat Data New technique for moving data among applications Integrates technique with existing applications by

packaging it as plugins of various kinds Stoitsev &al, EUD for Enterprise Proc / Info

New technique for EU tailoring of process models Represented as hierarchical to-do lists,

implemented as extensions to Outlook Sestoft, Implementing Function Spreadsheets

Added abstraction capability Realized as a special kind of sheet

Scaffidi

Sestoft

Stoitsev

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Evolution, development, maintenance

Data sharing: interoperability across apps Data from multiple applications must be combined

[Stoitsev, Wong] But data is often hard to share [Scaffidi, Doerner]

Evolution Evolution includes dynamic changes [Doerner] EU software evolves continuously [Costabile] EUs need an evolutionary perspective [Umarji]

Tailoring Individualized variants [Scaffidi, Stoitsev] EUs tailor businesses processes [Stoitsev, Doerner] Domain-specific tailoring for critical applications

[Praehofer] Personalizing workflows [el-Gayyar]

Constabile

Scaffidi

Praehofer

El-Geyyar

Doerner

Stoitsev

Wong

Umarji

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Data Sharing Interoperability Problems

Scaffidi &al, Topes to Validate, Reformat Data Many kinds of data are carried in short strings with

many formats: name, date, phone, address Applications assume different format, and

checking is binary, no “maybe” or special cases Topes offer format conversion, validation in [0..1]

Doerner, EU Development: SOA Challenges In SOA, problem for EU is gathering all the data for

a decision from various sources, DBs EUs want to export to Excel, but SAP can’t do this Also can’t exchange data between applications

Scaffidi

Doerner

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Evolution Doerner, EU Development: SOA Challenges

EUs develop and evolve their business processes They may not have enough info about process Major challenge is adaptation at runtime

Costabile, EUs as Unwitting Developers EUs often “program” without being aware of it Their software and adaptations keep evolving Solutions must extend through life cycle Case study shows structured planning for this

Constabile

Doerner

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Deliberate process for creating software

Shallow learning curve People need immediate gratification [Brandt] Gentle slope [Doerner, Stoitsev] Opportunistic programming [Brandt]

Need rules and process, but not the same as for production SW [Brandt] EU code is impermanent [Brandt]

Spectrum of users [Costabile]

EUs should know approaches to design and development, QA practices, evolutionary perspective, documentation, reuse [Umarji]

Some isolated Agile activities

Brandt

Constabile

Doerner

Stoitsev

Umarji

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Characteristics of EUs Brandt: Opportunistic Programming

Opportunistic software: nontrivial software, little upfront planning, ease and speed of development prioritized over robustness and maintainability

Not just sloppy programming, but good process for prototyping, ideation, discovery

Build from scratch using high-level tools Add new functionality via copy-and-paste Iterate rapidly Consider code impermanent Face unique debugging challenges

Costabile, EUs as Unwitting Developers EUs’ skills fall along a spectrum from EU to prof Less-skilled often start with tailoring Provide life cycle support, not just to release

Brandt

Constabile

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Educating EUs Umarji &al, Teaching SE to EUs

Surveyed bioinformatics curricula and recommended things that bioinformaticians should know about SE

Recommendations Approaches to software design and development Strong quality assurance (QA) practices Evolutionary perspective Documentation Reuse

Umarji

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Expressiveness and understandability

Visual interfaces to tools Define data formats with structured dialog and

examples [Scaffidi] Graphical composition [Stoitsev, El-Gayyar] Visual models [Doerner] Domain Oriented Visual Lang [Costabile]

Functional interface to visual tools to allow abstraction [Sestoft]

Chemical molecule metaphor for composition [Coutaz]

Use UML to create domain-specific languages [Shani]

People use informal cues to gauge quality of information [Brandt]

Brandt

Constabile

Scaffidi

Sestoft

El-Geyyar

Coutaz

Shani

Doerner

Stoitsev

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Questions for discussion What are, and how can we resolve, the

issues in the process tension between “opportunism” / gentle learning curve / instant

gratification / systematic process / consistency / long-term

usefulness How can an EU manage evolution without a

systematic process? Can we have a process with a shallow learning curve?

What are the potentials and problems for the technique of packaging a new capability variously as plugin, extension, macro in order to integrate it with various systems?