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

Issue	Cause	Solution
Cascade ignores project patterns	Missing/empty .windsurfrules	Add stack and architecture details
Rules truncated	Over 12,000 combined chars	Split into workspace rules with triggers
Wrong patterns for file type	No glob-triggered rules	Add `.windsurf/rules/` with glob triggers
Team inconsistency	No shared config	Commit `.windsurf/` directory to git
Slow indexing in monorepo	Root workspace open	Open specific package/app directory

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

Next Steps

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

windsurf-reference-architecture