StockBridge

Smart inventory sync with oversell protection and instant alerts for Shopify + Etsy.

Score: 8.0/10ArgentinaMedium BuildReady to Spawn
Brand Colors

The Opportunity

Problem

Small ecommerce business owners can't sync inventory across platforms like Shopify and Etsy, causing overselling and stockouts.

Solution

StockBridge syncs stock bidirectionally while holding virtual reserves to prevent oversells during sync delays. Custom rules let you set low-stock thresholds with SMS/email alerts. Track discrepancies in a simple audit log to resolve issues fast.

Target Audience

Small ecommerce business owners managing sales across multiple platforms like Shopify and Etsy

Differentiator

Built-in oversell prevention with smart holds – syncs safely even on flaky connections.

Brand Voice

supportive

Features

Shopify Integration

must-have8h

OAuth connect with inventory webhooks

Etsy Integration

must-have8h

OAuth connect with listing webhooks

Virtual Stock Holds

must-have15h

Reserve stock buffer during syncs to avoid oversells

Custom Sync Rules

must-have12h

Set schedules, thresholds per product/category

Real-time Alerts

must-have10h

SMS/email on low stock, failed syncs, discrepancies

Discrepancy Detector

must-have12h

Flag and auto-resolve stock mismatches

Rule Builder UI

must-have10h

No-code interface for sync rules

SMS Notifications

nice-to-have8h

Twilio-powered instant alerts

Audit Reports

nice-to-have7h

Exportable sync discrepancy reports

Scheduled Batches

nice-to-have6h

Nightly full syncs for efficiency

Total Build Time: 96 hours

Database Schema

users

ColumnTypeNullable
iduuidNo
emailtextNo
phonetextYes
plantextYes

integrations

ColumnTypeNullable
iduuidNo
user_iduuidNo
platformtextNo
credentialsjsonbNo
hold_bufferintNo

Relationships:

  • user_id -> users.id

inventory_items

ColumnTypeNullable
iduuidNo
integration_iduuidNo
skutextNo
quantityintNo
reservedintNo

Relationships:

  • integration_id -> integrations.id

alerts

ColumnTypeNullable
iduuidNo
user_iduuidNo
item_iduuidYes
typetextNo
resolvedboolNo
sent_attimestampYes

Relationships:

  • user_id -> users.id
  • item_id -> inventory_items.id

API Endpoints

POST
/api/integrations/connect

Connect platform & save creds

🔒 Auth Required
POST
/api/rules/create

Set custom sync rules/thresholds

🔒 Auth Required
GET
/api/alerts

Fetch user alerts

🔒 Auth Required
POST
/api/sync

Run sync with holds

🔒 Auth Required
POST
/api/webhooks/inventory

Process platform updates

Tech Stack

Frontend
Next.js 14 + Tailwind + React Hook Form
Backend
Next.js API + Supabase Functions
Database
Supabase Postgres
Auth
Supabase Auth
Payments
Stripe
Hosting
Vercel
Additional Tools
Twilio for SMSCron jobs via Vercel

Build Timeline

Week 1: Core setup

18h
  • Auth, DB schema
  • Landing & payments

Week 2: Integrations

28h
  • OAuth for both platforms
  • Basic sync

Week 3: Smart features

30h
  • Virtual holds
  • Rules UI

Week 4: Alerts & detector

25h
  • Discrepancy logic
  • Email/SMS

Week 5: Dashboard & logs

20h
  • Full UI polish
  • Reports

Week 6: Testing/deploy

12h
  • E2E tests
  • Launch prep

Week 7: Optimizations

10h
  • Performance tweaks
Total Timeline: 7 weeks • 143 hours

Pricing Tiers

Starter

$0/mo

100 items, no holds

  • Basic sync
  • Email alerts

Pro

$30/mo

None

  • Holds, rules, SMS
  • Unlimited items

Business

$79/mo

None

  • All + API, multi-user
  • Priority alerts

Revenue Projections

MonthUsersConversionMRRARR
Month 1806%$144$1,728
Month 660011%$1,980$23,760

Unit Economics

$45
CAC
$400
LTV
5%
Churn
90%
Margin
LTV:CAC Ratio: 8.9xExcellent!

Landing Page Copy

Protect Your Inventory: Smart Sync Shopify to Etsy

Virtual holds prevent oversells, alerts keep you safe – sync with confidence.

Feature Highlights

Oversell Protection Holds
Custom Rules & Thresholds
Instant Alerts
Discrepancy Auto-Fix
Secure Integrations

Social Proof (Placeholders)

"'Alerts saved my shop!' – Emma, Crafter"
"'No more stock nightmares.' – Tom, Retailer"

First Three Customers

Offer free Pro to first 10 in Etsy Seller Central forums complaining about oversells; run $50 FB ad to Shopify owners searching multi-channel; validate via Typeform in r/EtsySellers.

Launch Channels

Product Huntr/Etsyr/shopifyTwitter #ecommerceFacebook Groups

SEO Keywords

shopify etsy oversell preventioninventory sync alertsmultiplatform stock protectionetsy shopify stock alerts

Competitive Analysis

Sellbrite

sellbrite.com
$49+/mo
Strength

Broad channels

Weakness

No smart holds, steep learning

Our Advantage

Oversell focus + cheaper for small teams

🏰 Moat Strategy

User-defined rules dataset trains better discrepancy AI over time.

⏰ Why Now?

Supply chain disruptions make stockouts costlier; multi-channel sellers up 40%.

Risks & Mitigation

technicalhigh severity

Webhook delivery failures

Mitigation

Queue with retries, fallback polling

legallow severity

Platform ToS on automation

Mitigation

Read-only inventory API use only

Validation Roadmap

pre-build5 days

Survey 15 owners on oversell frequency

Success: 80% experienced monthly issues

mvp10 days

Live test with 3 betas

Success: Zero oversells in test period

Pivot Options

  • Pure alert service
  • Add Amazon
  • Forecasting add-on

Quick Stats

Build Time
143h
Target MRR (6 mo)
$5,000
Market Size
$500.0M
Features
10
Database Tables
4
API Endpoints
5