B2B SaaS Archetype¶
OWNER: aimee ALSO_USED_BY: anna, eric (contract), hugo (auth), faye, sytske
This archetype covers custom SaaS applications where the end-user is a business, not an individual consumer. The client's customers are organizations with teams, roles, billing relationships, and compliance requirements.
When This Archetype Applies¶
SCOPE_ITEM: Client is building software sold to other businesses SCOPE_ITEM: End-users operate within organizations (teams, departments, companies) SCOPE_ITEM: Billing is per-organization, not per-individual SCOPE_ITEM: Multi-tenancy is required (data isolation between customer orgs) SCOPE_ITEM: Enterprise readiness features are expected (SSO, audit logs, RBAC)
Archetype Variants¶
Horizontal SaaS¶
SCOPE_ITEM: horizontal_saas INCLUDES: Generic business function applicable across industries INCLUDES: Examples — project management, CRM, HR tools, invoicing, communication INCLUDES: Broad market, high competition, feature depth is differentiator CHECK: Client has clear differentiation strategy vs. established players CHECK: Pricing model accounts for high volume, lower ARPU
Typical scope range: 400-800 hours Typical features: Full feature tree minus vertical-specific modules
Vertical SaaS¶
SCOPE_ITEM: vertical_saas INCLUDES: Industry-specific solution (healthcare, logistics, legal, construction, agriculture) INCLUDES: Domain-specific workflows, terminology, compliance requirements INCLUDES: Smaller addressable market, higher ARPU, stickier customers CHECK: Client has deep domain expertise or domain advisor CHECK: Industry-specific compliance identified (HIPAA, PSD2, NEN, sector regulations)
Typical scope range: 500-1200 hours Typical features: Full feature tree plus domain modules, industry integrations
Internal Tools / Back-Office SaaS¶
SCOPE_ITEM: internal_tools INCLUDES: Software used by the client's own organization, not resold INCLUDES: Operational dashboards, internal workflow automation, reporting INCLUDES: Simpler auth (often SSO-only via corporate IdP) INCLUDES: No billing module, no public marketing site CHECK: Confirm whether this will EVER be resold — changes architecture fundamentally CHECK: Internal tools still need RBAC, audit trails, data export
Typical scope range: 200-500 hours Typical features: Reduced feature tree — no billing, no public onboarding
Process Automation Platform¶
SCOPE_ITEM: process_automation INCLUDES: Workflow builder, rule engine, form designer, approval chains INCLUDES: Integration-heavy (connects to client's existing stack) INCLUDES: Often replaces spreadsheets, email chains, or manual processes CHECK: Map the current manual process before designing automation CHECK: Identify all external systems that need integration
Typical scope range: 600-1500 hours Typical features: Full feature tree plus workflow engine, rule builder, form system
GE Stack for B2B SaaS¶
All B2B SaaS projects at GE use the following stack unless explicitly overridden:
| Layer | Technology | Notes |
|---|---|---|
| Frontend | Next.js (App Router) | React Server Components, TypeScript |
| API | Hono | Lightweight, edge-ready, type-safe routes |
| Database | PostgreSQL + Drizzle ORM | EU-hosted, RLS for multi-tenancy |
| Auth | Keycloak or NextAuth.js | Keycloak for enterprise SSO, NextAuth for simpler cases |
| Hosting | EU cloud (Hetzner / OVH / AWS eu-west) | GDPR data residency by default |
| Payments | Mollie (NL) PRIMARY | Stripe secondary for global (US-based — sovereignty risk) |
| Brevo (FR) or Mailjet (FR) | EU-hosted transactional email. Resend/Postmark secondary (US — sovereignty risk) | |
| Queues | Redis Streams or BullMQ | Background jobs, webhooks |
| Search | PostgreSQL FTS or Meilisearch | Meilisearch for complex search UX |
| File storage | S3-compatible (MinIO / Cloudflare R2) | EU region buckets |
COMPLIANCE: All deployments ISO 27001 and SOC 2 Type II aligned COMPLIANCE: All data stored in EU by default COMPLIANCE: DPA template provided to every client
Typical Scope Ranges¶
| Variant | MVP (hours) | Full Product (hours) | Enterprise-Ready (hours) |
|---|---|---|---|
| Horizontal SaaS | 300-500 | 500-800 | 800-1500 |
| Vertical SaaS | 400-600 | 600-1200 | 1200-2500 |
| Internal Tools | 150-300 | 300-500 | 500-800 |
| Process Automation | 400-700 | 700-1500 | 1500-3000 |
CHECK: If scope exceeds 1500 hours, decompose into phases CHECK: If MVP exceeds 600 hours, challenge scope — likely over-specced
Scoping Workflow¶
- Aimee receives intake from Dima (creative brief, client context)
- Aimee selects archetype variant
- Aimee walks feature tree (feature-tree.md) with client
- Each feature marked: REQUIRED / NICE_TO_HAVE / OUT_OF_SCOPE / PHASE_2
- Anna produces technical specification from marked feature tree
- Eric produces contract scope from specification
- Hugo produces auth architecture from SSO requirements
- Faye/Sytske (team PM) tracks delivery against feature tree
Pages in This Archetype¶
| Page | Purpose |
|---|---|
| Feature Tree | Complete feature decomposition |
| Authentication & SSO | Corporate SSO, SCIM, MFA |
| Multi-Tenancy | Data isolation strategies |
| RBAC | Roles, permissions, access control |
| Billing | Subscription models, payment integration |
| Onboarding | Setup wizards, data import, activation |
| Integrations | Webhooks, APIs, marketplace |
| Compliance | GDPR, SOC 2, audit logging |
| Checklist | Pre-delivery validation checklist |
Key Metrics for B2B SaaS¶
IF: Client asks "what should we measure?" THEN: Recommend these baseline metrics
| Metric | Target | Notes |
|---|---|---|
| Time to Value | < 2 minutes to first "aha" | Onboarding quality indicator |
| Activation Rate | > 40% | Users completing setup + core action |
| Trial-to-Paid | > 15% | Self-serve; 25%+ for sales-assisted |
| Monthly Churn | < 3% | Logo churn, not revenue churn |
| NPS | > 40 | Quarterly survey |
| ARPU | Depends on vertical | Track from day one |
Anti-Patterns to Flag During Scoping¶
CHECK: Client wants "AI everywhere" but cannot define specific use cases CHECK: Client wants to build a platform before validating a single workflow CHECK: Client scope includes features for 10k users but expects 50 at launch CHECK: Client wants custom everything — no standard patterns, no templates CHECK: Client cannot name their first 10 paying customers
IF: Any anti-pattern detected THEN: Flag to Dima and Dirk-Jan before proceeding with scoping
Effort Estimation Guidelines¶
Estimation uses the feature tree. Each SCOPE_ITEM has a typical hour range. Sum the selected items and apply a multiplier for project complexity.
| Complexity Factor | Multiplier | Examples |
|---|---|---|
| Standard B2B SaaS | 1.0x | Well-understood domain, standard features |
| Custom domain logic | 1.2x | Industry-specific rules, non-trivial workflows |
| Enterprise compliance | 1.3x | SOC 2 audit prep, custom DPA negotiation, pen testing |
| Multi-region deployment | 1.4x | EU + US data residency, multi-region infrastructure |
| Legacy migration | 1.5x | Data migration from existing system, API compatibility layer |
CHECK: Estimation is always a range (min-max), never a single number CHECK: Include 15% buffer for integration testing and bug fixing CHECK: Include client review cycles in timeline (not just dev hours)
Phase Decomposition¶
All projects above 400 hours are split into phases:
SCOPE_ITEM: phase_1_mvp INCLUDES: Core value proposition (the thing that makes the product worth using) INCLUDES: Authentication (email/password + social login at minimum) INCLUDES: Basic RBAC (predefined roles only) INCLUDES: Multi-tenancy (shared DB + RLS) INCLUDES: Billing (single plan, credit card payment) INCLUDES: Responsive web UI CHECK: Phase 1 must be usable by a real customer — not a demo
SCOPE_ITEM: phase_2_growth INCLUDES: SSO (SAML + OIDC) INCLUDES: Advanced billing (multiple plans, usage metering, billing portal) INCLUDES: Onboarding (setup wizard, data import, templates) INCLUDES: Integrations (webhooks, top 3 native integrations) INCLUDES: Reporting and dashboards CHECK: Phase 2 unlocks enterprise sales and self-serve growth
SCOPE_ITEM: phase_3_scale INCLUDES: SCIM provisioning INCLUDES: Custom roles and ABAC INCLUDES: App marketplace (OAuth2) INCLUDES: Zapier/Make integration INCLUDES: Advanced analytics and custom reporting INCLUDES: Native mobile app (if validated by market) CHECK: Phase 3 is post-product-market-fit — only if growth warrants investment