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  • Scrum PLoP
    • Scrum Tulip PLoP 2021 - Enkhuizen Netherlands
    • Scrum PLoP 2019
    • Scrum PLoP 2018, Quinta da Pacheca, Portugal
    • ScrumPLoP 2017, Quinta da Pacheca, Portugal
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  • Original Org Patterns Site
    • Organizational Patterns of Agile Software Development
      • Book Outline
        • Preface
        • History and Introduction
          • An Overview of Patterns and Organizational Patterns
          • What Are Patterns?
          • What Are Pattern Languages?
          • Organizational Pattern Languages
          • How the Patterns Came to Us
          • Gathering Organizational Data
          • Creating Sequences
          • History and Related Work
          • Introspection and Analysis of Organizations
          • Shortcomings of State of the Art
          • Analyzing Roles and Relationships
          • How to Use this Book
          • Reading the Patterns
          • Applying the Patterns
          • Updating the Patterns
          • Who Should Use This Book?
          • Size the Organization
          • The CRC-Card Methodology
        • The Pattern Languages
        • Organizational Design Patterns
          • Project Management Pattern Language
          • Community of Trust
          • Size the Schedule
          • Get On With It
          • Named Stable Bases
          • Incremental Integration
          • Private World
          • Build Prototypes
          • Take No Small Slips
          • Completion Headroom
          • Work Split
          • Recommitment Meeting
          • Work Queue
          • Informal Labor Plan
          • Development Episode
          • Implied Requirements
          • Developer Controls Process
          • Work Flows Inward
          • Programming Episode
          • Someone Always Makes Progress
          • Team per Task
          • Sacrifice One Person
          • Day Care
          • Mercenary Analyst
          • Interrupts Unjam Blocking
          • Don't Interrupt an Interrupt'
          • Piecemeal Growth Pattern Language
          • Size the Organization
          • Phasing It In
          • Apprenticeship
          • Solo Virtuoso
          • Engage Customers
          • Surrogate Customer
          • Scenarios Define Problem
          • Firewalls
          • Gatekeeper
          • Self-Selecting Team
          • Unity of Purpose
          • Team Pride
          • Skunkworks
          • Patron Role
          • Diverse Groups
          • Public Character
          • Matron Role
          • Holistic Diversity
          • Legend Role
          • Wise Fool
          • Domain Expertise in Roles
          • Subsystem by Skill
          • Moderate Truck Number
          • Compensate Success
          • Failed Project Wake
          • Developing in Pairs
          • Developing in Pairs
          • Engage Quality Assurance
          • Application Design is Bounded by Test Design
          • Group Validation
        • Organization Construction Patterns
          • Organizational Style Pattern Language
          • Few Roles
          • Producer Roles
          • Producers in the Middle
          • Stable Roles
          • Divide and Conquer
          • Conway's Law
          • Organization Follows Location
          • Organization Follows Market
          • Face-to-Face Before Working Remotely
          • Form Follows Function
          • Shaping Circulation Realms
          • Distribute Work Evenly
          • Responsibilities Engage
          • Hallway Chatter
          • Decouple Stages
          • Hub Spoke and Rim
          • Move Responsibilities
          • Upside-Down Matrix Management
          • The Water Cooler
          • Three to Seven Helpers per Role
          • Coupling Decreases Latency
          • People and Code Pattern Language
          • Architect Controls Product
          • Architecture Team
          • Lock 'Em Up Together
          • Smoke Filled Room
          • Stand Up Meeting
          • Deploy Along the Grain
          • Architect Also Implements
          • Generics and Specifics
          • Standards Linking Locations
          • Code Ownership
          • Feature Assignment
          • Variation Behind Interface
          • Private Versioning
          • Loose Interfaces
          • Subclass Per Team
          • Hierarchy of Factories
          • Parser Builder
        • Foundations and History
          • Organizational Principles
          • Priming the Organization for Change
          • Dissonance Precedes Resolution
          • Team Burnout
          • Stability and Crisis Management
          • The Open-Closed Principle of Teams
          • Team Building
          • Building on the Solid Core
          • Piecemeal Growth
          • Some General Rules
          • Make Love Not War
          • Organizational Patterns are Inspiration Rather Than Prescription
          • It Depends on Your Role in Your Organization
          • It Depends on the Context of the Organization
          • Organizational Patterns are Used by Groups Rather Than Individuals
          • People are Less Predictable than Code
          • The Role of Management
          • Anthropological Foundations
          • Patterns in Anthropology
          • Beyond Process to Structure and Values
          • Roles and Communication
          • Social Network Analysis
          • Distilling the Patterns
          • CRC Cards and Roles
          • Social Network Theory Foundations
          • Scatterplots and Patterns
        • Case Studies
          • Borland QuattroPro for Windows
          • A Hyperproductive Telecommunications Development Team
      • Appendices
        • Summary Patlets
        • Organization Book Patlets
        • Bibliography
        • Photo Credits
      • Mysteriously Missing
      • Supporting Pages
        • Common Pattern Language
        • Organizational Patterns
        • Diversity of Membership
  • Original Scrum Patterns Site Archive
    • Scrum as Organizational Patterns
    • Scrum Patterns Summary
    • Software Scrum Patterns
    • First-Level Scrum Patterns
  • The ScrumPLoP Mission
  • What is a PLoP?
Scrum Pattern Group

Fire Walls

Nobody gets past this point without my permission!

"A manager should be like the sweeper in curling: The sweeper runs ahead of the stone and sweeps away debris from the path of the stone so that the progress of the stone will be smooth and undisturbed — does this sound like your manager?" [BibRef-Gabriel1996]

Unfortunately, heavy human use in this same area could lead to bear/human interactions which could injure humans and cause management actions against the bear. — Sign at an entrance to Boulder Mountain Parks, Boulder, Colorado

...an organization of developers has formed in a corporate or social context where they are scrutinized by peers, funders, customers, and other "outsiders." Project implementers are often distracted by outsiders who feel a need to offer input and criticism. 

✥ ✥ ✥

It's important to placate stakeholders who feel a need to "help" by having access to low levels of the project, without distracting developers and others who are moving towards project completion.

Isolationism doesn't work: information flow is important. But communication overhead goes up non-linearly with the number of external collaborators. 

Many interruptions are noise. 

Maturity and progress are more highly correlated with being in control than being effectively controlled. 

Therefore: 

Create a ManagerRole, who shields other development personnel from interaction with external roles.** The responsibility of this role is "to keep the pests away." 

✥ ✥ ✥

The new organization isolates developers from extraneous external interrupts. To avoid isolationism, this pattern must be tempered with others, such as EngageCustomers and GateKeeper. 

This pattern was present in both BorlandQuattroProForWindows and in AHyperproductiveTelecommunicationsDevelopmentTeam. See also the pattern EngageCustomers, which complements this pattern. 

GateKeeper is a pattern that facilitates effective flow of useful information; FireWalls restricts detracting flow of (even potentially useful) information. You need a balance between them. In the park in Boulder, people (customers) come to see nature, and bears are a part of that nature. But if the customers interact too closely with the core contributors--to the point where it is a distraction--things can get out of control. Developers need information, and they can take advantage of customer contacts and GateKeepers to get the information they need. But they can also use managers as a shield. Furthermore, managers may need to step in to "help" developers who may be afraid to ask not to be bothered by customer contacts, or who are at risk of not fulfilling their own responsibilities if they are embroiled in customer matters. 

Be warned that if the organization fills this role with someone motivated largely by personal power, the potential damage to the organization can be large. If other roles like GateKeeper maintain good contact with other organizations, communications are more likely to remain open and FireWalls will more likely be called to account for self-serving actions. 

Sun Tzu notes: "He will win who has military capacity and is not interfered with by the sovereign." [BibRef-SunTzu1989]

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