battles / Subscriptions
Stay AI vs Submarine
Stay AI ($1,119/mo/mo, vibe code 6/10) vs Submarine ($500/mo/mo, vibe code 4/10). Stay AI is the easier one to rebuild yourself — here is what you lose either way.
Subscriptions
$1,119/mo/mo
- MVP
- 2-3 weeks
- Full replacement
- 3-6 months
easier to rebuild
get the build prompt →Subscriptions
$500/mo/mo
- MVP
- 3 weeks
- Full replacement
- 6-12 months, due to PCI-DSS scope, gateway tokenization, and Shopify Subscription API edge cases
price gap / year
$7,428/mo
running both / year
$19,428/mo
our call
Start with Stay AI — highest vibe code, weakest moat.
Stay AI
You can replace Stay AI's core subscription portal, skip/swap logic, and basic cancellation flows with an AI-generated app in a couple of weeks. However, matching their automated reinforcement-learning save flows, churn prediction models, and zero-touch migration services requires serious custom ML data engineering and ongoing operations.
you can rebuild
- Customizable drag-and-drop customer portal (swap, skip, pause, delay)
- Cancellation survey flows and retention save offers
- Bundles and build-your-own box UI
- Gamified digital punch cards and loyalty milestones
- One-click add-on upsells inside the customer portal
what you lose
- Proprietary reinforcement-learning models for dynamic retention save offers
- Turnkey white-glove migration team to transfer raw contract data from legacy platforms
- Dedicated human subscription growth strategist
- Pre-configured multi-channel integrations (Attentive, Postscript, Gorgias, Rebuy)
- Benchmarked retention analytics compared against industry-wide DTC cohorts
real moats
- Reinforcement learning models trained across hundreds of DTC subscription brands
- High-touch, human-led white-glove migration services and dedicated growth strategists
- Pre-built integrations with e-commerce stack tools (Attentive, Gorgias, Postscript, Klaviyo, Rebuy)
Submarine
Submarine sits between payment vaults, Shopify Subscription APIs, and enterprise headless checkouts. While setting up a basic recurring order trigger with Claude takes days, maintaining multi-gateway PCI compliance, zero-downtime token migrations, and resilient dunning at scale requires a dedicated backend team.
you can rebuild
- Fixed-interval subscription contract creation and scheduling
- Customer portal for order skips, pauses, and delivery date adjustments
- Transactional event webhooks for Klaviyo subscriber notifications
- Basic discount application on recurring orders
- Subscription product bundle configuration UI
what you lose
- Multi-gateway payment token vaulting and cross-processor payment routing
- PCI-DSS compliant payment token handoffs across custom checkouts
- Deep synchronization with Shopify Subscription Contracts GraphQL API
- Intelligent retry and dunning logic with automatic card update feeds
- Enterprise headless payment tokenization hooks
real moats
- PCI-DSS compliant tokenization infrastructure for multi-processor stores
- Deep architectural integrations with Shopify Subscription APIs and gateway vaults
- High switching cost and financial risk involved in migrating live payment tokens
open source escape hatches
- Lago AGPL-3.0
- Kill Bill Apache-2.0
- Active Merchant MIT
Questions people ask
Which is easier to rebuild with AI, Stay AI or Submarine?
Stay AI. It scores 6/10 on vibe code with a moat of 6/10, so an AI-assisted MVP takes about 2-3 weeks and a full replacement about 3-6 months.
Which one costs less, Stay AI or Submarine?
Submarine at $500/mo/mo for a typical mid-market store. The gap between the two is about $7,428/mo a year.
What do I lose if I replace Stay AI?
Proprietary reinforcement-learning models for dynamic retention save offers Turnkey white-glove migration team to transfer raw contract data from legacy platforms Dedicated human subscription growth strategist
What do I lose if I replace Submarine?
Multi-gateway payment token vaulting and cross-processor payment routing PCI-DSS compliant payment token handoffs across custom checkouts Deep synchronization with Shopify Subscription Contracts GraphQL API
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