Windsurf Reference Architecture

Windsurf Reference Architecture

Overview

Complete project architecture optimized for Windsurf AI. Covers workspace configuration, rules hierarchy, workflow organization, and team standardization patterns that maximize Cascade's effectiveness.

Prerequisites

• Windsurf IDE installed
• Team agreement on coding standards
• Repository with consistent project structure

Architecture Diagram

┌──────────────────────────────────────────────────────┐
│              Windsurf Workspace                       │
│  ┌───────────────┐  ┌────────────────────────────┐    │
│  │ .windsurfrules│  │ .windsurf/                 │    │
│  │ (AI context)  │  │  ├── rules/ (trigger rules)│    │
│  │               │  │  ├── workflows/ (automation)│    │
│  │               │  │  └── settings.json         │    │
│  └───────────────┘  └────────────────────────────┘    │
│  ┌───────────────┐  ┌────────────────────────────┐    │
│  │ .codeiumignore│  │ ~/​.codeium/                │    │
│  │ (index rules) │  │  ├── global_rules.md       │    │
│  │               │  │  ├── windsurf/​memories/    │    │
│  │               │  │  └── windsurf/​mcp_config   │    │
│  └───────────────┘  └────────────────────────────┘    │
├──────────────────────────────────────────────────────┤
│              Cascade AI Engine                        │
│  ┌───────────┐  ┌───────────┐  ┌─────────────────┐   │
│  │ Super-    │  │ Cascade   │  │ Command         │   │
│  │ complete  │  │ Write/​Chat│  │ (Inline Edit)   │   │
│  │ (Tab)     │  │ (Cmd+L)  │  │ (Cmd+I)         │   │
│  └───────────┘  └───────────┘  └─────────────────┘   │
├──────────────────────────────────────────────────────┤
│              Context Layers                           │
│  Rules > Memories > @Mentions > Open Files > Index   │
└──────────────────────────────────────────────────────┘

Instructions

Step 1: Project File Structure

my-project/
├── .windsurfrules              # AI context (stack, patterns, constraints)
├── .codeiumignore              # Indexing exclusions
├── .windsurf/
│   ├── settings.json           # IDE settings (committed)
│   ├── rules/
│   │   ├── testing.md          # trigger: glob **/​*.test.ts
│   │   ├── api-routes.md       # trigger: glob src/​routes/​**
│   │   ├── security.md         # trigger: model_decision
│   │   └── migrations.md       # trigger: manual
│   └── workflows/
│       ├── new-feature.md      # /​new-feature
│       ├── deploy-staging.md   # /​deploy-staging
│       ├── review-pr.md        # /​review-pr
│       └── quality-check.md    # /​quality-check
├── src/
│   ├── routes/                 # API route handlers
│   ├── services/               # Business logic
│   ├── repositories/           # Data access
│   └── types/                  # Shared types
├── tests/
│   ├── fixtures/               # Test data factories
│   └── services/               # Service unit tests
└── docs/
    └── architecture.md         # Architecture decisions

Step 2: Rules Hierarchy

# Priority order (highest to lowest):
rules_hierarchy:
  1_global_rules:
    path: ~/​.windsurf/​global_rules.md
    limit: 6000 chars
    scope: All workspaces
    use_for: "Personal coding preferences, universal standards"

  2_windsurfrules:
    path: .windsurfrules (project root)
    limit: 6000 chars
    scope: Current workspace
    use_for: "Project stack, architecture, conventions"

  3_workspace_rules:
    path: .windsurf/​rules/​*.md
    limit: 12000 chars each
    scope: Triggered by glob, model_decision, or manual
    use_for: "File-type-specific patterns, conditional rules"

  4_memories:
    path: ~/​.codeium/​windsurf/​memories/
    scope: Workspace-specific (auto-generated)
    use_for: "Decisions, discoveries (supplement, don't replace rules)"

# Total active chars: 12000 max (global + workspace rules combined)
# If exceeded: global rules take priority, workspace rules truncated

Step 3: Team Configuration Template

// .windsurf/​settings.json (committed to git)
{
  "codeium.indexing.excludePatterns": [
    "node_modules/​**", "dist/​**", ".next/​**",
    "coverage/​**", "*.min.js", "**/​*.map"
  ],
  "codeium.autocomplete.enable": true,
  "editor.formatOnSave": true,
  "editor.defaultFormatter": "biomejs.biome",
  "typescript.tsdk": "node_modules/​typescript/​lib",
  "files.associations": { "*.css": "tailwindcss" }
}

Step 4: Monorepo Strategy

monorepo/
├── .windsurfrules              # Shared conventions (brief)
├── .codeiumignore              # Broad exclusions
├── apps/
│   ├── web/
│   │   └── .windsurfrules      # Next.js-specific rules
│   └── mobile/
│       └── .windsurfrules      # React Native rules
├── packages/
│   ├── api/
│   │   └── .windsurfrules      # Express/​Fastify rules
│   └── shared/
│       └── .windsurfrules      # Library conventions
└── .windsurf/
    └── workflows/              # Cross-package workflows

# BEST PRACTICE: Open apps/​web/ or packages/​api/ directly
# NOT the monorepo root
# Cascade gets focused context per workspace window

Step 5: Context Pinning Strategy

## What to Pin in Cascade

Pin files that provide essential context:
- Type definition files (types/​*.ts)
- Architecture decision records (docs/​adr/)
- API schema files (openapi.yaml)
- Database schema (prisma/​schema.prisma, drizzle/​schema.ts)

How to pin:
- Click the pin icon next to a file in the Cascade context area
- Pinned files are always included in Cascade's context window
- Limit: pin 3-5 files max (more = diluted context)

Error Handling

Examples

Minimal .windsurfrules for Any Project

# Project: [name]
## Stack: [language] + [framework] + [database]
## Testing: [test framework]
## Conventions:
- [3-5 key coding patterns]
## Don't:
- [2-3 explicit anti-patterns]

Verify Architecture Setup

set -euo pipefail
echo "=== Windsurf Architecture Check ==="
echo "Rules: $([ -f .windsurfrules ] && wc -c < .windsurfrules || echo 'MISSING') chars"
echo "Ignore: $([ -f .codeiumignore ] && wc -l < .codeiumignore || echo 'MISSING') patterns"
echo "Rules dir: $(ls .windsurf/​rules/ 2>/​dev/​null | wc -l || echo 0) files"
echo "Workflows: $(ls .windsurf/​workflows/ 2>/​dev/​null | wc -l || echo 0) files"

Resources

• Windsurf Rules Directory
• Context Awareness
• Cascade Customizations Catalog

Next Steps

For workspace variant strategies, see windsurf-architecture-variants.