GetSignalHooks

Evidence-first hooks and follow-up emails from any company URL. A SaaS platform that generates research-backed outbound sales hooks using AI, with CRM integrations, automated follow-up sequences, and per-customer workflow automation.

Live at: https://www.getsignalhooks.com

Tech Stack

• Framework: Next.js 16.1.6 (App Router, Turbopack)
• Language: TypeScript
• Database: Turso (LibSQL/SQLite) via Drizzle ORM
• Auth: Auth.js v5 (NextAuth) with credentials provider, JWT sessions
• Payments: Stripe (Checkout, Customer Portal, Webhooks)
• Email: SendGrid with event webhook tracking
• AI: Anthropic Claude API (hook generation, email writing)
• Search: Brave Search API (company research)
• Styling: Tailwind CSS v4
• Deployment: Vercel (primary), Docker + Caddy (VPS option)

Architecture

src/
├── app/
│   ├── page.tsx                    # Landing page
│   ├── login/                      # Auth - sign in
│   ├── register/                   # Auth - sign up (with Stripe trial redirect)
│   ├── setup/                      # 5-step onboarding wizard
│   ├── docs/                       # API documentation
│   ├── contact/                    # Sales contact form
│   ├── forgot-password/            # Password reset request
│   ├── reset-password/             # Set new password
│   ├── privacy/                    # Privacy policy
│   ├── terms/                      # Terms of service
│   ├── unsubscribed/               # Unsubscribe confirmation
│   ├── followup-engine/            # Feature page
│   ├── not-found.tsx               # Custom 404 page
│   ├── global-error.tsx            # Sentry error boundary
│   ├── robots.ts                   # robots.txt generation
│   ├── sitemap.ts                  # sitemap.xml generation
│   ├── app/                        # Authenticated dashboard
│   │   ├── page.tsx                # Dashboard (stats, quick actions)
│   │   ├── hooks/                  # Hook generator UI
│   │   ├── leads/                  # Lead management + CSV upload
│   │   ├── analytics/              # Usage analytics
│   │   ├── sequences/              # Sequence builder UI
│   │   ├── inbox/                  # Draft approval + notifications
│   │   ├── batch/                  # Batch hook generation UI
│   │   └── settings/               # API keys, integrations, billing
│   ├── internal/                   # Internal admin tools
│   └── api/                        # 38 API route handlers
├── components/                     # 14 UI components
└── lib/
    ├── auth.ts                     # NextAuth configuration
    ├── stripe.ts                   # Stripe client + helpers
    ├── tiers.ts                    # Pricing tier definitions
    ├── tier-guard.ts               # Usage quota enforcement
    ├── rate-limit.ts               # Sliding window rate limiter
    ├── hooks.ts                    # Hook generation logic
    ├── db/                         # Drizzle schema + client
    ├── followup/                   # Follow-up engine (generate, sequences)
    ├── integrations/               # HubSpot + Salesforce OAuth & sync
    ├── n8n/                        # Docker container management
    ├── email/                      # SendGrid integration
    ├── intent.ts                    # Intent signal research + scoring
    └── reply-analysis.ts            # Reply classification + suggested responses

Database Schema

Table	Purpose
users	User accounts with tier, Stripe IDs, usage tracking, password change tracking, unsubscribe preference
accounts	OAuth provider accounts (Auth.js)
sessions	Active sessions (Auth.js)
verification_tokens	Email verification tokens
leads	Sales leads with status and sequence tracking
outbound_messages	Sent/queued emails with delivery status
audit_log	Event audit trail
usage_events	User activity tracking (hooks, emails, opens, clicks)
integrations	CRM connections (HubSpot, Salesforce)
n8n_instances	Per-customer n8n workflow containers
api_keys	Self-serve API keys (SHA-256 hashed, gsh_ prefix)
claim_locks	Distributed locks for concurrent processing
sequences	Custom outreach sequence definitions
lead_sequences	Lead-to-sequence assignment + progress
intent_signals	Cached buying signals per company
lead_scores	Computed lead temperature scores
notifications	In-app notification queue
hook_cache	Hook generation cache (48h TTL)
rate_limits	Rate limiting state
stripe_events	Idempotent Stripe event processing
workspaces	User workspaces
workspace_profiles	Workspace selling context

API Routes

Hook & Email Generation

Endpoint	Method	Description
/api/generate-hooks	POST	Generate hooks from company URL/name
/api/generate-hooks-batch	POST	Batch hook generation (up to 75 URLs)
/api/generate-followup	POST	Generate follow-up email with angle rotation
/api/generate-email	POST	Generate email from company URL

Lead Management

Endpoint	Method	Description
/api/leads	POST, GET	Create/list leads
/api/leads/[id]	GET	Get lead details
/api/leads/[id]/messages	POST	Log messages for a lead
/api/leads/send-followup	POST	Send scheduled follow-up

Follow-Up Engine

Endpoint	Method	Description
/api/followup/due	GET	Get leads due for follow-up
/api/followups/audit	POST	Log audit event
/api/followups/claim	POST	Claim lead for processing
/api/followups/pause	POST	Pause follow-ups
/api/followups/safety-check	POST	Pre-send safety check

CRM Integrations

Endpoint	Method	Description
/api/integrations/hubspot	GET	HubSpot connection status
/api/integrations/hubspot/callback	GET	OAuth callback
/api/integrations/hubspot/sync	POST	Trigger bidirectional sync
/api/integrations/salesforce	GET	Salesforce connection status
/api/integrations/salesforce/callback	GET	OAuth callback
/api/integrations/salesforce/sync	POST	Trigger bidirectional sync

Billing & Auth

Endpoint	Method	Description
/api/stripe/checkout	POST	Create Stripe Checkout session
/api/stripe/portal	POST	Open Stripe Customer Portal
/api/webhooks/stripe	POST	Stripe event webhook handler
/api/webhooks/sendgrid	POST	SendGrid event webhook handler
/api/webhooks/sendgrid-inbound	POST	Inbound reply parsing + classification
/api/auth/register	POST	User registration
/api/auth/[...nextauth]	*	NextAuth session routes
/api/auth/forgot-password	POST	Send password reset email
/api/auth/reset-password	POST	Reset password with token
/api/auth/verify-email	GET	Verify email address
/api/auth/resend-verification	POST	Resend verification email
/api/auth/delete-account	DELETE	Delete account + all data
/api/auth/unsubscribe	GET, POST	Email unsubscribe/resubscribe
/api/cron/onboarding-emails	GET	Onboarding drip sequence (Day 1/3/6)
/api/api-keys	POST, GET, DELETE	API key management

Sequences & Lead Sequences

Endpoint	Method	Description
/api/sequences	GET, POST	List/create sequences
/api/sequences/[id]	GET, PATCH, DELETE	Manage single sequence
/api/lead-sequences	POST	Assign sequence to lead
/api/lead-sequences/[id]	PATCH	Advance/update lead sequence

Intent Scoring

Endpoint	Method	Description
/api/leads/[id]/intent	POST	Score lead intent signals
/api/cron/intent-refresh	GET	Daily intent score refresh

Notifications & Drafts

Endpoint	Method	Description
/api/notifications	GET, PATCH	List/mark-read notifications
/api/notifications/[id]	PATCH, DELETE	Manage single notification
/api/drafts/[id]/approve	POST	Approve draft message
/api/drafts/[id]/reject	POST	Reject draft message

Workflows

Endpoint	Method	Description
/api/n8n-instances	POST, GET, PATCH	n8n container management
/api/n8n-templates	GET	List workflow templates

Pricing Tiers

Tier	Price	Hooks/Month	Batch Size	Key Features
Starter	£29	200	10	Evidence-backed hooks, basic sequences, role selection
Pro	£149	750	75	+ Multi-channel, intent scoring, inbox, reply analysis
Concierge	£499	10,000	75	+ Autonomous execution, white-glove setup

Getting Started

Prerequisites

• Node.js 20+
• pnpm

Local Development

# Install dependencies
pnpm install

# Copy environment variables
cp deploy/.env.example .env.local
# Fill in your API keys (see Environment Variables below)

# Run development server
pnpm dev

Open http://localhost:3000

Environment Variables

Required:

Variable	Description
TURSO_DATABASE_URL	Turso database URL (libsql://...)
TURSO_AUTH_TOKEN	Turso auth token
CLAUDE_API_KEY	Anthropic API key for hook/email generation
BRAVE_API_KEY	Brave Search API key for company research
AUTH_SECRET	Auth.js secret (generate: openssl rand -base64 32)
AUTH_URL	App URL (e.g. http://localhost:3000)
FOLLOWUP_ENGINE_API_TOKEN	Internal API auth token
SENDGRID_API_KEY	SendGrid API key for email sending
SENDGRID_FROM_EMAIL	Verified sender email address
STRIPE_SECRET_KEY	Stripe secret key
STRIPE_WEBHOOK_SECRET	Stripe webhook signing secret
STRIPE_PRICE_STARTER	Stripe Price ID for Starter tier
STRIPE_PRICE_PRO	Stripe Price ID for Pro tier
STRIPE_PRICE_CONCIERGE	Stripe Price ID for Concierge tier
NEXT_PUBLIC_APP_URL	Public app URL (e.g. https://www.getsignalhooks.com)

Optional (CRM integrations):

Variable	Description
HUBSPOT_CLIENT_ID	HubSpot OAuth app client ID
HUBSPOT_CLIENT_SECRET	HubSpot OAuth app client secret
SALESFORCE_CLIENT_ID	Salesforce Connected App client ID
SALESFORCE_CLIENT_SECRET	Salesforce Connected App client secret

Optional (VPS/Docker deployment):

Variable	Description
N8N_DOCKER_IMAGE	n8n Docker image (default: n8nio/n8n:latest)
N8N_PORT_START / N8N_PORT_END	Port range for n8n containers
N8N_DOCKER_NETWORK	Docker network name
APP_DOMAIN / N8N_DOMAIN	Domain names for Caddy
CADDY_ADMIN_URL	Caddy admin API URL

Database Migrations

Migrations are in drizzle/. Run them against your Turso database:

# Using Turso CLI
turso db shell <your-db-name> < drizzle/0000_faithful_calypso.sql
turso db shell <your-db-name> < drizzle/0001_add_api_keys.sql
turso db shell <your-db-name> < drizzle/0002_add_users_and_usage.sql
turso db shell <your-db-name> < drizzle/0003_add_stripe_fields.sql
turso db shell <your-db-name> < drizzle/0004_add_user_fields.sql

Or paste each file's contents into the Turso dashboard shell (remove --> statement-breakpoint lines).

Deployment

Vercel (Primary)

The app is deployed to Vercel at https://www.getsignalhooks.com.

# Deploy
vercel --yes --prod

Add all environment variables in Vercel project settings before deploying.

Docker / VPS

For self-hosted deployment with n8n container management:

# One-command VPS setup
scp deploy/setup-vps.sh user@your-server:~/
ssh user@your-server 'chmod +x setup-vps.sh && ./setup-vps.sh'

Or manually:

docker compose up -d

This runs the Next.js app + Caddy reverse proxy with automatic SSL.

Stripe Setup

1. Create 3 products in Stripe Dashboard (Starter £29, Pro £149, Concierge £499) as monthly recurring
2. Copy Price IDs to STRIPE_PRICE_STARTER, STRIPE_PRICE_PRO, STRIPE_PRICE_CONCIERGE
3. Create webhook endpoint at https://your-domain.com/api/webhooks/stripe
4. Subscribe to events: checkout.session.completed, customer.subscription.updated, customer.subscription.deleted
5. Copy webhook signing secret to STRIPE_WEBHOOK_SECRET

SendGrid Setup

1. Create SendGrid account and API key
2. Verify sender domain with DNS records (CNAME + TXT for DKIM/DMARC)
3. Set SENDGRID_API_KEY and SENDGRID_FROM_EMAIL

Optional (Monitoring & Cron):

Variable	Description
NEXT_PUBLIC_SENTRY_DSN	Sentry DSN for error monitoring
SENTRY_ORG	Sentry organization slug
SENTRY_PROJECT	Sentry project slug
SENTRY_AUTH_TOKEN	Sentry auth token (for source maps)
CRON_SECRET	Secret for authenticating Vercel Cron jobs

Key Features

• Evidence-First Hooks: AI generates hooks anchored on real public signals (earnings, hiring, tech changes) with evidence tier classification (A/B/C) and source citations
• Multi-Channel Variants: LinkedIn, cold call, video scripts alongside email hooks
• Custom Sequences: Multi-step, multi-channel sequence builder with templates
• Intent Scoring: Buying signal detection (hiring, funding, tech changes) with lead temperature
• Inbox & Approvals: Draft review, approve/reject, notification feed
• Reply Analysis: Inbound reply classification with suggested responses
• Autonomous Execution: n8n-based agentic sequences with guardrails
• Follow-Up Engine: Automated multi-step email sequences with angle rotation to avoid repetition
• CRM Sync: Bidirectional sync with HubSpot and Salesforce (OAuth, auto-refresh tokens)
• Per-Customer n8n: Isolated Docker containers for workflow automation per user
• Tier-Based Access: Monthly quota enforcement with automatic reset
• API Key System: Self-serve gsh_ prefixed keys with SHA-256 hashing and scope control
• Rate Limiting: In-memory sliding window with different limits per endpoint and auth status
• Email Analytics: SendGrid webhook tracking for opens, clicks, bounces, and replies
• Password Reset: Token-based password reset flow with rate limiting
• Email Verification: Verification emails on registration with resend capability
• Account Deletion: Full cascade delete with Stripe subscription cancellation and type-to-confirm safety
• Session Security: JWT refresh every 5 minutes, automatic invalidation on password change or account deletion
• Cookie Consent: GDPR/PECR compliant consent banner with essential/all cookie options
• Unsubscribe System: HMAC-signed unsubscribe tokens (CAN-SPAM/GDPR compliant)
• Onboarding Emails: Automated drip sequence (Day 1/3/6) via Vercel Cron
• Error Monitoring: Sentry integration (client, server, edge) with error replays
• Security Headers: HSTS, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy
• SEO: Open Graph/Twitter Card meta tags, robots.txt, sitemap.xml
• Legal Pages: Privacy Policy and Terms of Service