A repayment method for each contract.
Bullet, equal-principal or equal-payment schedules calculate the principal and interest for each installment.
All workMAKEWONDER / FINANCE
BUSINESS SYSTEMS / PRODUCT DESIGN & DEVELOPMENTEvery term.
Every term.
Every record.
Different contracts and calculations. Connected payments and records. A dedicated product for the details of everyday operations.
Explore the productMAKEWONDER FINANCEACTUAL PRODUCT / FICTIONAL SAMPLE DATA
See the whole picture.
Go straight to the record.
Open the ledgerGo straight to the record.
A Korean workspace connecting contracts, payments, a repayment calendar and a calculator.
Complex rules.
A clear working day.
When contract rules vary and payment records live elsewhere, even a small correction can mean checking several places. This tool is designed to connect that work into one coherent flow.
- PRODUCT
- Dedicated finance workspace
- OUR ROLE
- Workflow design · UX/UI · development
- CONNECTED RECORDS
- Contract → schedule → payment → correction
01 / CONTRACT LOGICDifferent terms.
Different terms.
Defined from the start.
Each contract defines its repayment method and interest basis. Scheduled amounts follow those terms; money received is kept as a separate payment record.
CONTRACT / SAMPLE 001
The contract is the starting point.
- Principal
- ₩10,000,000
- Annual rate
- 12.0%
- Repayment
- Bullet repayment
- Interest basis
- Monthly contract basis
10,000,000 × 12% ÷ 12₩100,000Scheduled interest for a pre-maturity installment · fictional contract
The period matters, too.
Choose a monthly basis, Actual/365 Fixed or Actual/Actual ISDA. Due dates follow the original contract day, adjusting to month-end when needed.
Keep scheduled and received apart.
Compare the calculated schedule with actual payments. Review the balance, next due date and unpaid amounts past their due date.
02 / FOLLOW THE RECORDA payment arrives.
A payment arrives.
The record stays clear.
A partial payment, a further payment and a correction. Amounts and history remain connected to the same contract.
ONE INSTALLMENT / FOUR MOMENTSPAYMENT FLOW / FICTIONAL CONTRACT
₩100,000 scheduled.
Nothing received yet.
This is the interest due for a pre-maturity installment. The scheduled principal for this installment is zero.
₩60,000 received.
₩40,000 remains.
Payment goes to the earliest unpaid installment, interest before principal. Here the entire amount is allocated to interest.
Another ₩40,000.
This installment is paid.
The interest for this installment is fully paid. The loan itself is not settled: its outstanding principal remains ₩10,000,000.
Correct the entry.
Keep its history.
Voiding the second entry makes ₩40,000 outstanding again. The original entry keeps its void time and reason, and is excluded from active payment totals.
SAMPLE 001 / INSTALLMENT 01Awaiting payment
INTEREST DUE THIS INSTALLMENT100,000 KRW
- Active payments
- ₩0
- Still outstanding
- ₩100,000
No payment recorded yet.
R-001Active payment
₩60,000R-002
₩40,000CORRECTION RECORD
R-002 · Voided: entry error
Void time and reason retained
Outstanding loan principal₩10,000,000
Monthly basis · annual 12% · bullet repayment · first installment. This explanatory sequence does not execute a payment or refund.
03 / KEEP THE HISTORYSee the present.
See the present.
Keep the history.
Corrections are part of operating a product. Downloaded files, contracts to merge and earlier saved states each serve a distinct purpose.
Export for the next use.
Export CSV for review and keep the complete JSON as a separate file, including contracts, payments and correction history.
Check before records combine.
JSON restoration merges only validated new contracts. A conflicting record or changed contract stops the entire merge.
Revisit the last 20 saved states.
Preview an earlier saved state before restoring it. These recent states live in the same database; downloaded JSON is kept separately for longer-term storage.
The details of the work.
The quality of the product.
This case connects contract calculations, payment allocation, corrections and record recovery. The same approach shapes dedicated systems for bookkeeping, reconciliation and contract operations.