enterprise Featured 2021

OpenChannel App Marketplace

Architected and developed OpenChannel's app marketplace platform, which grew to 500+ tenants hosting thousands of apps and serving roughly 100,000 API calls per day. Built developer app submission, the review workflow, and embeddable in-product storefronts. Engineered multi-gigabyte JSON import and export in constant memory using streaming I/O - imports read the source file through Apache Commons streaming APIs as a token stream and persist in chunks, exports fetch 100 records at a time onto a writable stream and write incrementally - run as background jobs with live progress in the UI. Designed the architecture and developed both backend and UI, with Spring Security and OAuth 2.0 for authentication and role-based authorization.

Client: Stocktree Inc.

Technologies Used

Spring Boot Spring Security OAuth2 Swagger Hibernate MongoDB AWS Angular 13 Bootstrap 4

Discuss Similar Project

What is OpenChannel App Marketplace?

OpenChannel is a white-label app marketplace platform that enables companies to build their own app ecosystems - similar to how Salesforce AppExchange or Slack App Directory work. As a full-stack developer and architect, I was instrumental in building the platform from its early stages.

The platform consists of several interconnected components: a developer portal where third-party developers can register and submit their apps, a review system for marketplace administrators, and embeddable marketplace widgets that companies can integrate into their products. I designed the overall architecture to be highly customizable, allowing each customer to brand and configure their marketplace according to their needs.

On the backend, I built robust APIs using Spring Boot with comprehensive security implemented through Spring Security and OAuth2. The system uses MongoDB for flexible data storage, which was crucial for handling the varied metadata structures of different app types. I implemented Swagger documentation to ensure the APIs were well-documented and easy for customers to integrate with.

The frontend was built with Angular 13 and Bootstrap 4, creating a responsive experience that works seamlessly across desktop and mobile devices. I paid special attention to the developer experience, making the app submission process intuitive and providing clear feedback throughout the review cycle.

OpenChannel grew to serve major enterprise customers before being acquired by Stripe in 2021, which speaks to the quality and scalability of the platform we built.

By the Numbers

500+

Marketplace tenants

1000s

Apps hosted

~100K

API calls per day

Multi-GB

Imports in constant memory

What does it do?

White-label marketplace: developer app submission, admin review workflow, and embeddable in-product storefronts
Multi-gigabyte JSON import and export that runs in constant memory - no full-file buffering, no temporary disk growth proportional to dataset size
Imports read the source file through Apache Commons streaming APIs as a token stream and persist in chunks
Exports fetch 100 records at a time, convert onto a writable stream, and write incrementally
Both run as background jobs with live progress streamed to the UI, so large migrations never block the interface or hit request timeouts
Spring Security with OAuth 2.0 for authentication and role-based authorization across every service
Swagger-documented REST APIs consumed directly by customer marketplaces

How was it built?

The interesting constraint was tenant data migration. Marketplace datasets ran to gigabytes of JSON, and the obvious implementation - parse the document into memory, then write it out - fails on file size alone and takes the pod with it. Both directions were rebuilt around streaming: reads are a token stream persisted in chunks, writes page 100 records at a time onto a writable stream. Memory use is therefore flat regardless of dataset size, and disk is never asked to hold a second copy. Running the transfer in the background with live UI progress removed the request-timeout ceiling that had capped how much a tenant could move at once.