DurableSave: Autosave and Idempotent Write Guard for Accounting Apps

Legal & Professional Services
🔥
9/10
Demand Score
Unsaved invoices/journals force costly rework and missed billing; silent write failures are hard to detect and reconcile.
🌊
9/10
Blue Ocean
Competition Level
💰
$39-149
Price/Month
Predicted customer spend
⏱️
8 days
Time to MVP
Difficulty: Moderate

The Problem

A secure browser extension + edge proxy that makes data entry in cloud accounting apps durable. It captures field-level edits locally, autosaves drafts every few seconds, and persists them offline. On

🔗 Validated by Real User Complaints

This problem has been verified through 5 real user complaints:

Competitor Landscape

  • Native autosave in QBO/Xero (limited)
  • Generic form recovery extensions (e.g., Lazarus legacy)
  • Password/session keepalive tools
  • In-house scripts

Must-Have Features for MVP

Autosave every 3–10 seconds with encrypted local cache
Offline draft mode with cross-device restore
Idempotent API wrapper with ordered retry/backoff
Session expiry detection and pre-submit reauth prompts
Field-level change diff and conflict warnings
Draft governance (retention, export, purge policies)
Admin console with app allowlist and policies
Audit logs of drafts vs final submissions
Role-based controls and SSO (SAML/OIDC)

⚠️ Potential Challenges

  • Content Security Policy and extension store reviews
  • Different DOM structures per app and UI updates
  • Protecting PII in local cache (encryption, zero-knowledge)
  • Maintaining true idempotency across vendor APIs
  • Enterprise SSO/2FA flows

Risk Level: Low

🎯 Keys to Success

  • ≥90% reduction in lost work tickets
  • <0.5% rate of duplicate submissions post-install
  • >30% faster completion for long forms
  • Zero PII leakage incidents; SOC2 compliance
  • Adoption by >80% of targeted data-entry staff

Ready to Build This?

This moderate-difficulty project could be your next micro-SaaS success.