kasama.loan
Whitepaper · v1.0

Settling casual debts without the awkwardness.

A two-way verification ledger for the loans friends and family actually make — built mobile-first for the Philippines, open to everywhere.

Author: kasama.loan Status: Live Updated: June 2026
01 — Abstract

Abstract

Most money lent between people who know each other leaves no trace. A friend covers your share of dinner; a cousin borrows for tuition; a workmate spots you for a concert ticket. The amounts are small enough to be informal and large enough to quietly corrode a relationship when memory and goodwill diverge.

kasama.loan is a free, mobile-first ledger for exactly these loans. Its defining mechanism is a two-way confirmation loop: a debt is only “real” once both parties have acknowledged it, turning a one-sided claim into a mutually agreed record. From that shared record, kasama can generate calendar reminders and tamper-evident PDF documents that either party — or a neutral third party — can verify. The service runs entirely on edge infrastructure, keeps money in integer centavos to avoid rounding drift, and is sustained by an unobtrusive free tier plus an optional Pro subscription.

In one sentence

kasama replaces “I’m pretty sure you owe me” with a record both people already agreed to.

02 — Problem

The quiet cost of an informal “utang”

In Filipino, utang is a casual debt, and lending within one’s circle is woven into daily life. That informality is a feature socially and a bug financially. Three failures recur:

Spreadsheets and notes apps solve only the lender’s memory — they are still one-sided. Formal lending apps over-solve it, importing credit checks, interest-by-default and collections energy that have no place between a parent and child. kasama sits deliberately in the gap: structured enough to be a record, light enough to use between people who love each other.

03 — Positioning

What kasama is

Kasama is the Filipino word for a companion — the person you are with. The name is the thesis: this is a tool for money between people who are already on the same side.

kasama is a tracker and an agreement layer, not a lender. No money moves through it. It never advances funds, charges interest, or pursues collection. It records what two people decided, helps them remember it, and — when they want — gives them a document to prove it. It is Philippine-first in language, currency formatting, and payment vernacular (GCash, Maya, bank transfer, cash), but nothing about it is country-locked.

Track casual loans and more, settled without the awkwardness.
04 — Core mechanism

The Confirmation Wall

The heart of kasama is a refusal to let one person unilaterally define a debt. When a lender logs a loan, it does not enter the ledger as fact. It enters as a pending request addressed to the borrower, who must explicitly confirm or reject it. Only on confirmation does the loan become active and start counting in either person’s totals.

Lender logs loan Borrower sees request Both agreed · active

This single design choice produces most of kasama’s value:

Why a wall, not a notification

A notification can be ignored; an unconfirmed loan simply isn’t counted. The friction is the point — it guarantees that everything in the ledger was mutually acknowledged.

05 — State model

The ledger lifecycle

Every loan is a small state machine. Beyond the active path, kasama models the full social reality of casual debt — including the graceful ways debts end without being repaid.

pending active settled
alternate endings → rejected forgiven hidden
Settle
The debt was paid back. It closes and leaves the running balance.
Forgive
The lender writes the debt off deliberately — a first-class action, because “never mind it” is how a great many real loans actually end.
Hide
Remove a loan from your totals without forgiving it — a middle ground for debts you’re not chasing but don’t want to formally cancel.
Reject
The borrower disputes the request before it ever becomes active. Nothing enters the ledger.

Balances are computed from the event history rather than stored as a mutable number, and every amount is held in integer centavos — so repeated interest or split-the-bill math never accumulates floating-point drift.

06 — Scope

Beyond one-to-one

Casual debt is rarely a clean pair of people. kasama scales the same confirmation principle up to groups and out to people who haven’t joined yet.

🤝

Friends

Add people by a stable User ID. Friendship is a request the other side accepts — with a cooldown to stop repeat spam.

Circles

Reusable groups (housemates, the barkada) for one-tap selection. A person can belong to any number of circles.

🧾

Events & splits

Log a trip or dinner’s expenses, split them, and “settle up” — which fans out into individual loans each member confirms.

👤

Guests

Lend to someone with no account via a claim link or QR; the record binds to them the moment they sign up.

Interest and installments exist for the rarer, larger loan that genuinely needs them — opt-in, never the default, with custom repayment intervals bounded to a sensible 7–30 days. Group events can be joined by scanning an event QR, which adds the scanner to the split automatically.

07 — Proof

Verifiable documents

For loans that warrant it, kasama generates a clean, formal PDF acknowledgement of the debt. Each document carries a SHA-256 fingerprint of its canonical loan data and a QR linking to a public verification page.

It is worth being precise about what this does and does not prove:

Honest framing

kasama is not a notary and a kasama PDF is not a court instrument. It is strong, checkable evidence that both parties agreed to a specific record — which for the overwhelming majority of personal loans is exactly the assurance that was missing.

Showing a counterparty’s verified email on a document is strictly opt-in, requested per loan from each party.

08 — Reminders

Reminders, without the spam

Chasing a debt is the awkward part, so kasama offloads it to tools people already trust. Each loan with a due date exports an iCalendar (.ics) entry — compatible with Google, Apple, and Outlook calendars — and every user gets a private, subscribable feed of all their upcoming due dates that refreshes on its own.

The reminder then comes from the borrower’s own calendar, not a guilt-laden message from the lender. No push-notification machinery, no nagging, no app required to be open.

09 — Trust

Trust & data ownership

A ledger of who-owes-whom is sensitive by nature, so the defaults lean private.

10 — Architecture

Architecture

kasama runs as a single application deployed to the edge, chosen for low latency to a globally distributed user base and for cost that scales to near-zero at rest.

Framework
Next.js (App Router) with React, server-rendered.
Runtime
Cloudflare Workers via the OpenNext adapter; Smart Placement co-locates compute with the database.
Data
Cloudflare D1 (SQLite at the edge) for the ledger; R2 object storage for receipt images, with lifecycle cleanup and a hard storage cap.
Money
Integer centavos end-to-end; formatting localised at the edge.
Documents
PDF generation with an embedded serif typeface and an SHA-256 verification hash.
Integrity
Repository pattern with parallel in-memory implementations, exercised by a deterministic test suite on every deploy.

The data model follows a repository pattern: each domain (users, transactions, contacts, circles, events) has an interface with both an edge-database implementation and an in-memory one, which keeps the business logic — the ledger state machine, balance computation, clearing — fast to test and independent of infrastructure.

11 — Sustainability

Sustainability & pricing

kasama must pay for itself without compromising the casual experience. The prime directive on monetisation is restraint: ads are inline and unobtrusive only — never pop-ups, interstitials, or anything that interrupts the core flow — and Pro removes them entirely.

PlanPriceWhat you get
Free ₱0 The full ledger, friends, circles, events, guests, reminders. Supported by unobtrusive inline ads. One interest-bearing loan included; pay-per-document for formal PDFs.
Pro · monthly ₱150/mo Ad-free, unlimited interest/installment loans, and formal verifiable PDFs included.

Three revenue lines — restrained ads on the free tier, the Pro subscription, and pay-per-document — are deliberately layered so the product can cover its edge-infrastructure costs before it is widely known, while keeping the essential tracker free forever.

12 — Roadmap

Roadmap