Empowering Teams: Decentralized Architecture Decisions

Key Takeaways

• Teams can make any decision after seeking advice from affected parties and documenting it in an Architectural Decision Record (ADR).
• Context maps ensure clear team ownership of system areas.
• Use architectural principles, immutable ADRs, and weekly advisory forums to maintain alignment.
• Teams evolve through four phases: disbelief → excitement → consequences → self‑correction.
• Architects act as facilitators between teams rather than sole decision-makers.

---

Learning from Slime Mold: A Metaphor for Decentralized Architecture

Image source

Physarum polycephalum, or slime mold, solves complex problems without a central brain — creating efficient networks purely through localized decisions.

Scientists tested this by placing food sources in positions matching Tokyo’s cities and watched slime mold replicate aspects of the Tokyo subway network — often more efficiently than the real system.

Lesson: In software architecture, similar decentralization can outperform centralized “ivory‑tower” approaches — provided teams have context, communication channels, and clear principles.

---

Image after 26 hours: The slime mold network closely matched Tokyo’s subway.

Source

---

Our Transformation Journey

In 2020, the organization faced:

• Legacy systems with multiple .NET versions and tangled dependencies
• Manual, error-prone deployments using installers
• Release cycles lasting 3–6 months
• Long user acceptance tests and repeated bug fixes

Goal: Re-architect into a cloud-native SaaS platform aligned with modern engineering practices — requiring not just technical change, but a cultural shift toward decentralized decision-making.

---

Establishing Teams for Fast Flow

Following Team Topologies, teams were restructured into:

• 3 Product Engineering Teams
• 1 Enabling Team (subject matter experts)
• 1 Platform Team (initial re-platforming, then cognitive load reduction)

Core requirement: Architecture must be loosely coupled and distributed to empower teams to solve problems efficiently.

---

The Advice Process: Foundation for Empowerment

The Advice Process enables any team to make decisions if they:

• Seek advice from stakeholders and experts.
• Document decisions publicly with rationale.
• Record situations where advice was ignored, noting pros and cons.

Supporting tools:

• Architectural Principles — decision guidelines
• Architectural Decision Records (ADRs) — immutable documentation
• Architectural Advisory Forum (AAF) — weekly collaborative review

---

Creating the Context Map

Purpose: Define clear boundaries and ownership before autonomous decision-making.

• Used domain-driven design and context mapping
• Identified bounded contexts and relationships/contracts
• Assigned each bounded context to one team

Challenges: Legacy dependencies made separation difficult.

Outcome: A single source of truth for business flows and team ownership.

First version shows scale and complexity.

---

Continuous Refinement

• Grey areas: No clear ownership — must be resolved.
• Shared contexts: Multiple teams depend on them — can cause contention.

Benefits:

• Visualizing dependencies helps forecast impact before changes.
• Encourages collaboration and reduces unnecessary coupling.

---

Architectural Principles: Guiding Decisions

Collaboratively developed in workshops tied to business strategy.

Each principle includes:

• Statement of intent
• Link to strategy
• Concise rationale
• Implications (positive & negative)

Example: Isolate tenant database — aligns with business objectives but increases hosting costs.

---

Architectural Decision Records (ADRs)

A precise, structured way to capture one architectural decision and its reasoning.

Typical ADR fields:

• ID and title
• Author
• Status (draft, accepted, superseded)
• Decision (1–3 sentences)
• Principles influencing the choice
• Context
• Alternatives considered (pros/cons)
• Consequences
• Advice received

Immutable: Once adopted, can only be superseded — not edited.

Usage: Over five years, >200 ADRs produced, serving as living documentation and onboarding resource.

---

Architectural Advisory Forum (AAF)

Weekly cross-team meeting with agenda:

• Upcoming spikes (tech investigations)
• Upcoming ADRs — presentations/questions
• DORA metrics and Azure spend
• SLO dashboards — system performance

Purpose: Transparency, feedback, and early issue visibility.

---

Case Study: First ADR in Practice

Context: Complex legacy Line of Business (LoB) module with quality issues and monolithic design.

Decision: Convert LoB to an independent microservice:

• Dedicated datastore (Azure Cosmos DB)
• Default configuration
• Independent deployment and scaling

Outcome:

• Maintained contracts with dependent contexts via dual writes
• Reduced interdependencies and performance bottlenecks

Lessons learned:

• Link product-level context via Product Decision Records
• Break big changes into smaller ADRs
• Seek advice earlier and filter opinion vs. actionable feedback

---

The Evolution of Decision-Making

Teams progress through:

• Unaware of autonomy
• Seeking validation from leadership
• Leadership holds line against centralizing again
• Full ownership with context & shared vision

Eventually:

• Decisions flow naturally
• Consequences teach valuable lessons
• Teams self-regulate and provide peer feedback

---

Benefits & Outcomes

• Trust & transparency: Teams decide within constraints.
• Alignment: Teams contribute to one product vision.
• Architect role shifts to facilitation and complex problem-solving.
• Faster delivery & greater ownership.

---

Conclusion

Like slime molds, empowered teams can build efficient, adaptive systems when supported by clear structure:

• Context maps — clarity & ownership
• Architectural principles — alignment
• Immutable ADRs — decision memory
• Advisory forums — collaboration

Result: Faster delivery, better alignment, higher engagement, and stronger architecture — with architects free to focus on high-value systemic work.

---

Would you like me to produce a condensed visual summary of this transformation that teams can use for onboarding and workshops? It could turn this into a one-page Architecture Empowerment Canvas.