One-liner: FiberSplit turns shared subscriptions into self-balancing group accounts—no reminders, no reimbursement requests, no spreadsheets—using Fiber payment channels for instant, automated, per-member settlement.
Team: Salman
Blockchain developer specializing in developer tooling, security, and payment integrations.
GitHub: salmansarwarr Discord: salmansarwarr32
Project Overview
Hundreds of millions of people share subscriptions every month—Netflix, Spotify, YouTube Premium, Microsoft 365, Claude, ChatGPT, and countless other digital services. While sharing reduces costs, managing payments remains surprisingly manual. One person pays the bill, everyone else owes money, and every month someone has to send reminders, chase payments, and recalculate costs whenever the group changes.
FiberSplit removes that friction entirely.
Members authorize a spending limit once through a Fiber payment channel session. From that point onward, FiberSplit automatically settles each person’s share through Fiber every billing cycle. If someone joins or leaves, costs are recalculated automatically without spreadsheets, reimbursement requests, or manual transfers.
FiberSplit demonstrates how Nervos Fiber enables a consumer application that traditional payment rails cannot deliver economically. Rather than simply tracking who owes money, FiberSplit automates settlement itself.
The Problem
Shared subscriptions create a recurring administrative burden for millions of users.
- One person floats the full bill every month.
- Reimbursement depends on people remembering — and many don’t.
- Adding or removing a member means manually recalculating everyone’s share.
- Partial-month joins and leaves are annoying enough that most groups simply ignore proration and absorb the unfairness.
- Existing payment methods make recurring $3–10 settlements inefficient due to transaction fees.
None of this is a hard problem individually. It’s a frequency problem: it happens every month, for every subscription, in every group, forever — which is exactly the kind of recurring, small-value, trust-minimized flow that Fiber payment channels are designed to support.
The Solution
FiberSplit automates subscription cost-sharing end-to-end using Fiber.
- A user creates a subscription group with its monthly cost, billing date, and invited members.
- Each member authorizes a spending limit through a Fiber payment channel session, which can be revoked at any time.
- On each billing date, FiberSplit automatically settles each member’s share to the subscription owner through Fiber.
- If membership changes, FiberSplit automatically recalculates future payments and applies any necessary proration.
The result is a subscription that behaves like a self-balancing group account instead of a monthly IOU chain.
Example Workflow
Alice subscribes to Spotify Family for $20/month and creates a FiberSplit group with Bob, Carol, and David.
Each member authorizes an $8 monthly spending cap, providing a small buffer for prorated adjustments while ensuring FiberSplit can never exceed the approved limit.
Initial Group
| Member | Monthly Share |
|---|---|
| Alice | $5.00 |
| Bob | $5.00 |
| Carol | $5.00 |
| David | $5.00 |
On the billing date, Fiber automatically settles each member’s payment to Alice.
- No invoices.
- No reminders.
- No manual transfers.
Mid-Cycle Change
Halfway through the month, David leaves the group.
FiberSplit automatically:
- Calculates David’s partial usage.
- Applies the appropriate proration.
- Updates future recurring payments.
The next billing cycle becomes:
| Member | Monthly Share |
|---|---|
| Alice | $6.67 |
| Bob | $6.67 |
| Carol | $6.67 |
The adjustment happens automatically without requiring anyone to calculate or request payments.
Why Fiber
FiberSplit relies on capabilities that traditional payment infrastructure cannot provide efficiently.
- Near-Instant Settlement: Payments move immediately when they are due rather than waiting for banking settlement windows.
- Low-Cost Micropayments: Recurring payments of only a few dollars remain economically viable because Fiber payment channels avoid the fixed costs associated with traditional card networks.
- Programmable Spending Limits: Users approve a monthly spending cap once through a Fiber payment channel session. FiberSplit cannot exceed those authorized limits, and permissions can be revoked at any time.
- Automatic Rebalancing: Membership changes simply update payment channel state rather than requiring new payment requests or repeated authorization.
Traditional bill-splitting applications solve the accounting problem. FiberSplit solves the settlement problem by automating the movement of money.
MVP Scope
| Feature | Included in MVP |
|---|---|
| Wallet connection & user registration |  |
| Subscription group creation | |
| Member invitations | |
| Equal-split billing | |
| Percentage-based custom splits | |
| Mid-cycle proration on join/leave | |
| Automated recurring Fiber payments | |
| Payment history dashboard | |
| Real-time balance tracking | |
| Merchant/direct billing integration |  (Future) |
| Multi-currency support | (Future) |
Target Users
- Friends sharing entertainment subscriptions (Netflix, Spotify, YouTube Premium)
- Families managing shared household services
- Students splitting software licenses
- Remote teams sharing SaaS tools
- Small businesses with collaborative subscriptions
Comparison
| Feature / Capability | Manual Apps | FiberSplit |
|---|---|---|
| Tracks who owes what | |
|
| Moves money automatically | |
|
| Viable at $5/month scale | (but manual) |
|
| Auto-recalculates on membership change | |
|
| Revocable, programmable limits | |
|
Success Metrics
- Number of active subscription groups created
- % of billing cycles completed with zero manual intervention
- Median time from “member leaves” to “recalculated split applied”
- Average settlement latency (target: under one second)
- Retention: groups still active after 3 billing cycles
Budget
Total requested: $1,200
| Category | Amount |
|---|---|
| Core development (smart contract / Fiber payment channel logic) | $500 |
| Frontend & dashboard development | $300 |
| Spending authorization & security review | $250 |
| Testing, deployment & documentation | $150 |
| Total | $1,200 |
Milestones
Milestone 1 — Core Infrastructure & Wallet Integration ($300)
- Set up project repo, CI, and dev environment
- Implement wallet connection and user registration
- Integrate Fiber payment channel authorization flow
- Establish base Fiber payment channel connectivity
Deliverable: users can connect a wallet and authorize a spending limit
Milestone 2 — Subscription Group Management ($300)
- Build subscription group creation flow (cost, billing date, members)
- Implement member invitations and group membership state
- Implement equal-split billing logic
- Implement percentage-based custom splits
Deliverable: users can create a group and define how costs are split
Milestone 3 — Automated Billing & Proration Engine ($350)
- Implement automated recurring Fiber settlement on billing date
- Implement mid-cycle proration logic for joins/leaves
- Implement automatic recalculation of future payments on membership change
- Enforce spending caps and handle revocation
Deliverable: billing cycles run automatically and rebalance correctly on membership changes
Milestone 4 — Dashboard, Testing & Launch ($250)
- Build payment history dashboard
- Build real-time balance tracking view
- End-to-end testing across group creation, billing, and membership changes
- Write documentation and publish MVP
Deliverable: fully functional, tested MVP ready for users
Future Enhancements
- Rent and household bill splitting
- Merchant integrations for direct subscription billing
- Shared family budgets
- Organization and team subscription management
- Multi-currency support
- Calendar reminders and payment notifications
- AI-powered recommendations for fair cost allocation
Why This Project
FiberSplit demonstrates how Nervos Fiber enables a payment experience that is difficult to achieve on traditional financial rails. Instead of simply recording shared expenses, it automates recurring settlement with programmable spending permissions, instant payment channels, and dynamic group rebalancing.
It showcases major component of the Fiber infrastructure through a real consumer application while solving a familiar, high-frequency problem that millions of users already experience.
By transforming subscription sharing into an automated, self-balancing payment system, FiberSplit provides a practical demonstration of Nervos Fiber’s instant settlement, programmable spending permissions, and low-cost micropayments. It delivers a real-world consumer application that highlights the capabilities of Fiber.