Architecture Decisions (ADRs)¶

This page provides access to all Architecture Decision Records (ADRs) for the WebGrip platform, documenting significant architectural choices, their rationale, and evolution over time.

What are ADRs?¶

Architecture Decision Records (ADRs) document important architectural decisions made during the development and evolution of the platform. They capture:

• Context: The situation that led to the decision
• Decision: What was decided and why
• Consequences: The positive and negative impacts of the decision
• Status: Whether the decision is proposed, accepted, rejected, or superseded

ADR Repository¶

Location: docs/adrs/ Format: MADR (Markdown Architecture Decision Records) Template: docs/adrs/0000-template.md

ADR Template Structure¶

Our ADRs follow the MADR v3+ format with WebGrip-specific enhancements:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51

# ADR NN – Concise Title

* **Status**: Proposed │ Accepted │ Rejected │ Deprecated │ Superseded by ADR‑NN
* **Deciders**: Names of people who give formal approval
* **Date**: YYYY‑MM‑DD
* **Tags**: Domain::Subdomain, Security, Performance, etc.
* **Version**: 1.0.0

## Context and Problem Statement
[Background, constraints, and core problem]

## Decision Drivers
[Why this matters - performance targets, compliance requirements, etc.]

## Considered Options
1. Option A – summary
2. Option B – summary  
3. Option C – summary

## Decision Outcome
### Chosen Option
[Selected option]

### Rationale
[Why this option was superior]

### Positive Consequences
* [Benefits]

### Negative Consequences / Trade‑offs
* [Costs and limitations]

### Risks & Mitigations
* [Identified risks and mitigation strategies]

## Validation
* **Immediate proof** – links to tests, PoCs, benchmarks
* **Ongoing guardrails** – monitoring, alerts, KPIs

## Compliance, Security & Privacy Impact
[Data classification, threat model updates, regulatory compliance]

## Notes
* **Related Decisions**: ADR‑NN, ADR‑MM
* **Supersedes / Amends**: ADR‑KK if any
* **Follow‑ups / TODOs**: JIRA‑123, etc.

### Revision Log
| Version | Date | Author | Change |
|---------|------|--------|--------|
| 1.0.0   | YYYY‑MM‑DD | Name | Initial creation |

Current ADRs¶

ADR Index¶

📝 Note: As of the current repository state, only the ADR template exists. This section will be populated as architectural decisions are documented.

ADR Categories¶

As the platform evolves, ADRs should be categorized by domain:

Infrastructure Decisions¶

• Kubernetes Platform Choices: Why DOKS over other providers
• Container Runtime: OCI runtime selection and configuration
• Network Architecture: CNI selection and network policies
• Storage Solutions: Persistent volume and backup strategies

Security Decisions¶

• Secret Management: SOPS + Age vs. other secret solutions
• Access Control: RBAC configuration and authorization patterns
• Certificate Management: cert-manager vs. manual certificate handling
• Network Security: Network policies and security boundaries

Observability Decisions¶

• Monitoring Stack: Prometheus + Grafana selection rationale
• Logging Strategy: Log aggregation and retention policies
• Alerting Policies: Alert fatigue prevention and escalation
• Metrics Collection: Which metrics to collect and store

Development Experience Decisions¶

• CI/CD Platform: GitHub Actions vs. other CI/CD solutions
• Application Templates: Standardized application bootstrapping
• Documentation Platform: Backstage TechDocs selection
• Development Workflows: Git workflows and review processes

Technology Choices¶

• Ingress Controller: Traefik vs. NGINX vs. other options
• Service Mesh: Whether to adopt a service mesh and which one
• Database Platform: Database technology choices and patterns
• Message Queuing: Event streaming and message queue solutions

Creating ADRs¶

When to Create an ADR¶

Create an ADR when making decisions that:

• Affect Multiple Teams: Cross-cutting concerns that impact multiple components
• Have Long-term Impact: Decisions that are difficult or expensive to reverse
• Involve Trade-offs: Choices between competing technical approaches
• Establish Patterns: Decisions that set precedents for future development
• Impact Security/Compliance: Changes affecting security posture or compliance
• Require Stakeholder Buy-in: Decisions needing broader organizational approval

ADR Creation Process¶

Step-by-Step ADR Creation¶

1. Copy Template:

   1 2	# Copy the template to create a new ADR cp docs/adrs/0000-template.md docs/adrs/NNNN-descriptive-title.md

2. Number Assignment:

   • Use sequential numbering (0001, 0002, etc.)
   • Check existing ADRs to determine next number
   • Reserve numbers for in-progress ADRs

3. Fill Out Sections:

   • Context: Describe the problem and constraints
   • Options: Research and document 3-5 viable alternatives
   • Decision: Clearly state what was decided
   • Rationale: Explain why this option was chosen
   • Consequences: Document both positive and negative impacts

4. Stakeholder Review:

   • Share with relevant technical leads
   • Include security and compliance review if applicable
   • Incorporate feedback and update draft

5. Approval Process:

   • Technical approval from domain experts
   • Management approval for significant decisions
   • Security sign-off for security-impacting decisions

6. Implementation Tracking:

   • Link to implementation tasks or tickets
   • Define success metrics and monitoring
   • Schedule follow-up reviews

ADR Review Guidelines¶

Review Criteria: - [ ] Problem statement is clear and specific - [ ] Multiple options were considered - [ ] Decision rationale is well-documented - [ ] Consequences (both positive and negative) are identified - [ ] Validation approach is defined - [ ] Security and compliance impact assessed - [ ] Implementation plan is clear

Review Participants: - Technical Lead: Domain expertise and technical feasibility - Security Engineer: Security implications and compliance - Platform Engineer: Infrastructure and operational impact - Product Owner: Business alignment and priority

ADR Lifecycle Management¶

ADR Status Transitions¶

Maintenance Procedures¶

Quarterly ADR Review: - Review all "Accepted" ADRs for continued relevance - Update status to "Deprecated" for outdated decisions - Create new ADRs for evolved approaches - Update implementation links and validation results

ADR Updates: - Minor updates: Update version number and revision log - Major changes: Consider creating a new ADR that supersedes the original - Status changes: Update status and add superseding ADR references

ADR Archive Management¶

File Organization:

1
2
3
4
5
6
7
8

docs/adrs/
├── 0000-template.md              # Template for new ADRs
├── 0001-kubernetes-platform.md   # Platform choice
├── 0002-secret-management.md     # Secret management approach
├── 0003-monitoring-stack.md      # Observability decisions
├── 0004-ingress-controller.md    # Ingress solution choice
└── superseded/                   # Archived superseded ADRs
    └── 0002-old-secret-mgmt.md

Archival Process: - Move superseded ADRs to superseded/ directory - Update references in superseding ADRs - Maintain redirect or reference in main ADR list

Integration with Development Process¶

ADR Requirements in Development¶

For Infrastructure Changes: - New platform component adoptions require ADR - Major configuration changes need ADR review - Security model changes must have ADR approval

For Application Patterns: - New application architecture patterns - Development toolchain changes - CI/CD workflow modifications

ADR Review in Pull Requests¶

Pull Request Template should include:

1
2
3
4
5

## Architecture Decision Record
- [ ] This change requires an ADR (significant architectural decision)
- [ ] ADR has been created and approved: [Link to ADR]
- [ ] This change implements an existing ADR: [Link to ADR]
- [ ] No ADR required (minor change with no architectural impact)

ADR Impact Assessment¶

Before Implementation: - Review existing ADRs for conflicts or dependencies - Assess whether new ADR supersedes existing decisions - Identify stakeholders who need to be informed

During Implementation: - Reference ADR in code comments for context - Include ADR links in configuration documentation - Update ADR with implementation lessons learned

After Implementation: - Validate ADR predictions against actual outcomes - Update ADR with real-world results and metrics - Schedule periodic review based on validation plan

Tooling and Automation¶

ADR Generation Tools¶

ADR CLI Tools (Optional enhancements):

1
2
3
4
5
6
7
8

# Install ADR tools (if team decides to adopt)
npm install -g adr-log adr-viewer

# Generate ADR index
adr-log -d docs/adrs/ > adr-index.md

# Create interactive ADR browser
adr-viewer -d docs/adrs/ -o adr-browser/

Integration with Documentation¶

TechDocs Integration: This page automatically links to ADRs in the repository: - Direct Links: Links point to ADR files in the repository - Status Tracking: ADR status is maintained in the individual files - Search Integration: ADRs are searchable through TechDocs search

Backstage Integration: ADRs can be linked from component entities:

1
2
3

# In component definitions
annotations:
  backstage.io/adr-location: docs/adrs

Contributing to ADRs¶

ADR Contribution Guidelines¶

Who Can Create ADRs: - Technical leads and architects - Senior engineers making significant architectural decisions - Product managers for cross-cutting business decisions - Security engineers for security-related architectural choices

ADR Quality Standards: - Clear problem statement with business context - At least 3 alternative options considered - Explicit trade-offs and consequences documented - Validation approach with measurable outcomes - Regular review and update schedule defined

ADR Communication¶

Notification Process: - New ADRs shared in team channels and all-hands meetings - Status changes communicated to affected teams - Quarterly ADR summary in engineering updates

Training and Onboarding: - New team members review key ADRs during onboarding - ADR writing workshops for technical leads - Regular "ADR retrospectives" to review decision outcomes

Related Resources¶

Architecture Documentation¶

External References¶

• MADR Template: Markdown Architecture Decision Records format
• ADR GitHub Organization: Tools and resources for ADRs
• Architecture Decision Records: Original ADR concept by Michael Nygard

📋 ADR Maintenance: ADRs are living documents that should evolve with the platform. Schedule regular reviews and updates to ensure they remain accurate and valuable.