battles / Subscriptions
Loop Subscriptions vs Submarine
Loop Subscriptions ($399/mo/mo, vibe code 7/10) vs Submarine ($500/mo/mo, vibe code 4/10). Loop Subscriptions is the easier one to rebuild yourself — here is what you lose either way.
Subscriptions
$399/mo/mo
- MVP
- 2-3 weeks
- Full replacement
- 6-9 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
$1,212/mo
running both / year
$10,788/mo
our call
Start with Loop Subscriptions — highest vibe code, weakest moat.
Loop Subscriptions
You can easily build a custom Shopify subscription app that eliminates Loop's 1% transaction fee using native Shopify APIs in a few weeks. However, replacing Loop's deep app store integration ecosystem, white-glove migration scripts, and battle-tested dunning algorithms requires significant ongoing development.
you can rebuild
- Basic recurring product subscriptions (Shopify Selling Plans integration)
- Self-serve customer portal for skips, pauses, and product swaps
- Basic cancellation save flows with pause/discount offers
- Automated payment recovery (dunning retries)
- Shopify Theme App Extensions for selling plan widgets on product pages
what you lose
- Managed migration support to transfer active vaulted payment tokens from older platforms.
- Out-of-the-box native integrations with marketing and support tools (Klaviyo, Gorgias, Attentive).
- Dedicated Customer Success Manager and shared Slack support channel.
- Gamified retention features like loyalty streak tracking and mystery rewards.
- Built-in A/B testing infrastructure for cancellation flows.
real moats
- Turnkey white-glove data migration pipelines from legacy systems like Recharge or Skio without subscription downtime or token loss.
- Deep ecosystem integrations (Klaviyo, Gorgias, Smile.io, Attentive) built over years with dedicated webhooks and state syncing.
- Battle-tested payment retry logic optimized against millions of historical transactions to maximize recovery rates.
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, Loop Subscriptions or Submarine?
Loop Subscriptions. It scores 7/10 on vibe code with a moat of 4/10, so an AI-assisted MVP takes about 2-3 weeks and a full replacement about 6-9 months.
Which one costs less, Loop Subscriptions or Submarine?
Loop Subscriptions at $399/mo/mo for a typical mid-market store. The gap between the two is about $1,212/mo a year.
What do I lose if I replace Loop Subscriptions?
Managed migration support to transfer active vaulted payment tokens from older platforms. Out-of-the-box native integrations with marketing and support tools (Klaviyo, Gorgias, Attentive). Dedicated Customer Success Manager and shared Slack support channel.
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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