All work

Payments · SaaS architecture

Flexible billing without fragile access control

A Stripe subscription system covering free, monthly, quarterly, and yearly plans alongside voucher-based promotions.

Role

Full-stack engineer · System design and implementation

Stack

Stripe · Node.js · MongoDB · Webhooks · Next.js

Timeline

[Add timeline]

[Add anonymized product image or recreated UI]02

Project details, identifiers, visuals, and metrics have been generalized to respect confidentiality.

The challenge

Turning complexity into a product people can trust.

The platform needed flexible pricing while keeping billing state and product access consistent through renewals, cancellations, upgrades, failed payments, and promotions.

My approach

Designed from the system out.

01

Integrated Stripe subscriptions and modeled plan entitlements independently from the payment provider.

02

Designed webhook handling around repeat delivery and safe state synchronization.

03

Supported free-tier access, multiple billing intervals, and voucher-driven product rules.

System view

[Add or refine architecture diagram]

InputApplicationQueue / ServicesOutcome

Impact

What changed.

[Add subscription or conversion result]

[Add number of plans / vouchers processed]

[Add reliability outcome]

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