Stack Index
Stack Index — Function → Greenlit Tool
This is the greenlit-tool registry — the canonical function → tool lookup and the first place to answer "what do we use for X?". One row per function, grouped by domain, with columns Function · Role · Vendor · Product. Each tool's role, wiring, and rationale live on the linked Foundation page — click the Product cell to jump to the detail.
How to read the markers. ⚠️ = undecided / WIP / gap (an open bake-off, not a decision). ⏸ = deferred (a decision consciously postponed). Rows without a marker are locked. Anything carrying a ⚠️ is listed again in Open & deferred decisions so an agent never mistakes an in-flight bake-off for a settled choice.
Product — Frontend & Client
| Function | Role | Vendor | Product |
|---|---|---|---|
| Web application UI | Engineering | Open source / Google | Vite + TanStack (Router + Query) → Cloud Run |
| Marketing site | Eng / Marketing | Open source / Google | Next.js 14 → Cloud Run |
| Mobile app | Engineering | Expo (OSS) | Expo + React Native |
| Product auth | Engineering | Better Auth (OSS) | Better Auth (self-hosted on app server) |
| Feature flags / experiments | Eng / Product | PostHog | PostHog Cloud (Boost+, BAA) — flags + experiments |
| Marketing CMS | Marketing / Eng | Sanity | Sanity (Growth) |
Product — Backend, Data & AI
| Function | Role | Vendor | Product |
|---|---|---|---|
| Backend API | Engineering | Open source / Google | FastAPI (Python) → Cloud Run |
| API contract | Engineering | Open source | OpenAPI → openapi-typescript client |
| OLTP database | Engineering | Neon | Neon Scale (Postgres, HIPAA / BAA) |
| Authorization (app-level) | Engineering | Cerbos (OSS) | Cerbos PDP (policy-as-code YAML/CEL; Query Plan → SQL filters) + Neon RLS floor |
| Schema & migrations | Engineering | Drizzle (OSS) | Drizzle Kit (schema/) |
| Vector search / retrieval | Engineering | Neon | pgvector (in Neon) |
| OLAP warehouse | Eng / Data | BigQuery | |
| Data transform (ELT) | Data / Eng | dbt Labs | dbt (BigQuery) |
| Durable execution | Engineering | Restate | Restate (Restate Cloud, managed) — durable agent runtime + human-in-the-loop |
| AI — reasoning / embeddings / voice | Engineering | Vertex AI — Gemini | |
| LLM observability / evals | Engineering | PostHog | PostHog Cloud (Boost+, BAA) — LLM observability + evals |
| Home-care platform / EHR | Eng / Clinical | WellSky | WellSky Personal Care (API integration) |
| Caregiver scheduling AI (on WellSky) | Ops / Eng | ⚠️ TBD | ⚠️ Bake-off: Zingage vs Phoebe vs Alden |
| Product voice / telephony | Engineering | Telnyx (+ Google) | ⚠️ WIP — Pipecat + Telnyx / Gemini Live |
Product — Infrastructure, DevOps & Observability
| Function | Role | Vendor | Product |
|---|---|---|---|
| Cloud platform | Engineering | GCP (Cloud Run, GCS, Artifact Registry, WIF) | |
| Infrastructure as code | Engineering | Pulumi | Pulumi Cloud |
| CI / CD | Engineering | GitHub (Microsoft) | GitHub Actions |
| Source control | Engineering | GitHub (Microsoft) | GitHub Team + Copilot |
| Edge / CDN / DNS / WAF | Engineering | Cloudflare + Google | Cloudflare Pro (marketing + DNS) · GCP Cloud Load Balancing + Cloud Armor (app/API PHI edge) |
| Secrets management | Engineering | Pulumi + Google | Pulumi ESC + GCP Secret Manager |
| Observability | Engineering | OpenTelemetry → Cloud Logging / Trace / Monitoring | |
| Error tracking (client + app) | Engineering | Google + PostHog | GCP Error Reporting + PostHog error tracking; Sentry as escalation path |
| Alerting / on-call | Engineering | Cloud Monitoring alert policies + SLOs → Teams / email (PagerDuty later) | |
| Backups / DR | Engineering | Neon + Google | Neon PITR, BigQuery time-travel, GCS versioning |
| Object storage | Engineering | GCS (CMEK + signed URLs) — uploads / documents | |
| Caching / rate-limit store | Engineering | Neon (Redis deferred) | Neon now; Memorystore (Redis) when pressure appears |
| Monorepo / build | Engineering | Open source | Turborepo |
| Lint / format | Engineering | Open source | Biome (TS) · Ruff (Py) |
| Git hooks | Engineering | Open source | Lefthook |
| Local dev environment | Engineering | Open source | Devbox + direnv + process-compose |
| Remote dev environments | Engineering | Coder | Coder (self-hosted on GCP) |
| VPN / tailnet (non-prod access) | Engineering | Tailscale | Tailscale — internal LB + subnet router; gates previews / staging / Coder (prod stays public, no BAA needed) |
| Coding agent | Engineering | Anthropic / GitHub | ⚠️ WIP — Claude Code (primary) + GitHub Copilot |
Product build — Collaboration & Knowledge
| Function | Role | Vendor | Product |
|---|---|---|---|
| Project / product management / issues | Product / Eng | Linear | Linear Business — product docs live in Notion |
| Docs / knowledge base | All (product) | Notion | Notion Business / Enterprise |
| Meeting notes / transcription | All | Notion | Notion AI Meeting Notes — bundled with Notion Business (replaces Granola) |
| Design / prototyping | Product / Eng | Figma | Figma Professional — design system + brand source of truth |
Business Ops — Productivity, Communication & Identity
| Function | Role | Vendor | Product |
|---|---|---|---|
| Office suite / email / calendar | All staff | Microsoft (primary) | Microsoft 365 (primary) · Google Workspace (secondary) |
| Enterprise productivity AI | All staff | Microsoft / Google | ⚠️ Bake-off — M365 Copilot vs Gemini for Workspace |
| Team chat | All staff | Microsoft | Microsoft Teams (bundled with M365) |
| Project management (business) | All staff / Ops | Notion | Notion — business task + milestone tracking (distinct from Linear for product) |
| Workforce identity / SSO / MFA | IT / All | Microsoft | Microsoft Entra ID (P1 → P2) |
| Device management (MDM) | IT | Rippling → Microsoft | Rippling device mgmt initially (Pro) → Microsoft Intune later |
| Endpoint security / EDR | IT / Security | Microsoft | Microsoft Defender for Business |
| Data governance / DLP / labels | IT / Compliance | Microsoft | Microsoft Purview |
| Password / secrets manager (people) | All staff | 1Password | 1Password |
Business Ops — People, Finance & Legal
| Function | Role | Vendor | Product |
|---|---|---|---|
| HR / payroll / benefits | HR / Ops | Rippling | Rippling Core HR + Payroll |
| Finance / accounting | Finance | Sage | Sage Intacct |
| Corporate cards / expense | Finance | Ramp | Ramp |
| E-signature | Legal / Ops | Dropbox | Dropbox Sign (Standard, annual + BAA) |
| Compliance / GRC (HIPAA program) | Compliance / Security | ⏸ Deferred | ⏸ Vanta / Drata — deferred to Q1 2027 (pre-go-live) |
| Legal / contracts / entity mgmt | Legal | Outside counsel | No dedicated tooling yet |
| Business insurance | Ops / Finance | Specialist broker | Home-care broker — prof. liability + GL + workers' comp + non-owned auto + abuse; cyber/D&O via broker or Vouch/Embroker |
Business Ops — Corp Dev / M&A
The acquisition motion (~a dozen deals over ~5 years) gets first-class functions.
| Function | Role | Vendor | Product |
|---|---|---|---|
| Virtual data room (diligence / fundraising) | M&A / Legal | Peony | Peony Data Rooms (flat per-admin subscription) · SharePoint convention retained for small tuck-ins |
| Deal pipeline / target tracking | M&A / Exec | Notion | Notion target database; revisit 4Degrees or Affinity at >25 active targets or first corp-dev hire |
Business Ops — Sales, Marketing & Support
| Function | Role | Vendor | Product |
|---|---|---|---|
| Sales data / enrichment | Sales / Partnerships | Clay | Clay (Growth) — referral-source dev |
| Cold outreach / deliverability | Sales / Partnerships | ReachInbox | ReachInbox (Growth) — channel/referral outreach |
| CRM / prospect funnel | Product / GTM | Built-in + WellSky | Product-native funnel (HomeCareHQ) + WellSky referral mgmt + BigQuery analytics — no traditional CRM |
| Product analytics | Product / Growth | PostHog | PostHog Cloud (Boost+, BAA) — analytics + funnels + session replay (content) |
| Customer support / helpdesk | Support / CX | WellSky + built-in | WellSky Family Room + product agent + shared inbox — dedicated helpdesk (Front) deferred until volume warrants |
| Transactional email (product) | Engineering | AWS | AWS SES (free self-serve BAA; us-west-2, co-located with Neon) — no PHI in bodies |
| Marketing / lifecycle email | Marketing / Growth | ⚠️ TBD | ⚠️ Bake-off: Customer.io vs Iterable vs Loops (BAA gating) |
| Patient comms — SMS / voice | Ops / Clinical | Telnyx | Telnyx (shared with product) |
| Fax (referrals / clinical) | Clinical / Ops | WellSky | WellSky referral / e-fax intake (AI-summarized); SRFax fallback |
Inherited (legacy systems)
Systems inherited at close. Disposition (keep / migrate / sunset) is unresolved for every row — each is a ⚠️ gap, not a greenlit choice, and none is documented in Foundation yet.
| Function | Role | Vendor | Product |
|---|---|---|---|
| SOPs & internal knowledge base | Ops / All staff | Trainual | ⚠️ Trainual (keep vs migrate to Notion unresolved) |
| Care management (GCM / ECM) | Clinical / Ops | CareTree | ⚠️ CareTree (case management + invoicing, ~$560/mo; disposition unresolved) |
| Caregiver training (LMS) | HR / Clinical | CareAcademy | ⚠️ CareAcademy (onboarding + compliance training; disposition unresolved) |
| Office VOIP / phones | Ops / All staff | RingCentral | ⚠️ RingCentral (overlap with Teams and Telnyx unresolved) |
| Virtual assistant staffing | Ops / HR | Sphere Rocket | ⚠️ Sphere Rocket / OLIVIA (disposition unresolved) |
| Background checks / credentialing | HR / Compliance | Guardian (CA DSS) | ⚠️ Guardian (DOJ/FBI fingerprint clearance; disposition unresolved) |
Open & deferred decisions
Every ⚠️ / ⏸ row above, collected so an agent never treats an in-flight bake-off as a locked choice.
⚠️ Undecided / WIP — these are open bake-offs, not decisions:
- Enterprise productivity AI — M365 Copilot vs Gemini for Workspace.
- Marketing / lifecycle email — Customer.io vs Iterable vs Loops (gated on BAA availability).
- Caregiver scheduling AI (on WellSky) — Zingage vs Phoebe vs Alden; see AI Tier.
- Product voice / telephony — Pipecat + Telnyx / Gemini Live (WIP).
- Coding agent — Claude Code (primary) + GitHub Copilot (WIP).
- Inherited legacy systems — Trainual, CareTree, CareAcademy, RingCentral, Sphere Rocket, Guardian; keep / migrate / sunset all unresolved.
⏸ Deferred — a decision consciously postponed:
- Compliance / GRC (HIPAA program) — Vanta / Drata, deferred to Q1 2027 (pre-go-live). The underlying HIPAA controls still apply now regardless of tooling.
See also:
- The Stack (Pricing) — per-tool pricing for the greenlit stack
- Business Operations — the non-product IT / ops stack in detail
- HIPAA Compliance — the trust zone, vendor BAAs, and PHI-free surfaces