Development of an NFT marketplace

The LeverX team created an attractive, user-friendly marketplace for selling NFT packages.

Customer

A U.S.-based sports NFT seller operating in the semi-professional and non-professional sports segment. The company was building a business around large volumes of sports-related digital content, working with athletes, teams, and sports communities across multiple disciplines.

Challenge

The client was building an NFT marketplace that supported both initial sales and secondary resale within a single platform. The goal was to remove the need for external services and keep the entire transaction flow in one place. Development started in August 2021, when the NFT market was growing rapidly, while user confidence in new platforms remained uneven.

Since the solution was developed from scratch, several practical issues had to be addressed early on.

Reliability

The platform needed to clearly communicate reliability and trustworthiness through UI and UX. This applied both to the marketplace itself and to individual sellers, as users had to feel confident when buying and reselling digital assets. At the same time, the experience had to remain intuitive and accessible for users with different levels of familiarity with NFTs and blockchain technology.

Regulatory compliance

The platform had to align with federal and state laws governing cryptocurrency-related businesses in the United States, which required careful consideration of legal and operational constraints from the early stages of development.

Scalable framework for NFT resale

The client needed a fully functional secondary marketplace that would allow users to resell NFTs directly within the platform. This required designing a secure, transparent, and scalable mechanism for peer-to-peer transactions without compromising performance or user experience.

Solution

The LeverX—Emerline team developed a comprehensive NFT marketplace that supports the full lifecycle of digital assets, from primary issuance to secondary resales, all within a single environment. Our approach focused on building a platform from the ground up that remains reliable under load while staying fully compliant with industry regulations.

To deliver a responsive interface, we used React for the front end, paired with a Python-based back end for better scalability. For asset security, we integrated Arweave to provide permanent, decentralized storage for all digital content. The entire infrastructure is hosted on AWS, which gives the platform the stability needed for long-term growth.

Handling financial operations required a multi-layered integration strategy. We utilized Circle for seamless in-app payments and wallet funding, while incorporating ACH and Wire transfers for secure withdrawals. To maintain compliance with U.S. cryptocurrency regulations, we built ONfido directly into the onboarding flow to manage Know Your Customer (KYC) verification.

The secondary marketplace was a critical part of this build. We prioritized transaction integrity here, developing specific logic to prevent simultaneous purchase attempts and ensure that ownership transfers remain transparent and secure for every user on the platform.

Key features

• Intuitive UI/UX with animated NFT drop unpacking
• Clubhouse-like registration flow
• Built-in KYC verification
• User accounts and a dedicated admin panel
• Secondary marketplace for NFT resale
• Protection against simultaneous purchases
• In-app payments and fund withdrawal functionality
• Compliance with federal and state regulations governing NFT marketplaces

Technology Stack

The solution was built on a scalable cloud-based architecture, ensuring performance, security, and readiness for high user activity during NFT drops and secondary market trading.

Cloud infrastructure: AWS

Amazon Web Services were used as the core cloud environment to support scalability, fault tolerance, and secure operations across all platform components.

Networking and content delivery: AWS VPC, AWS CloudFront with S3

AWS Virtual Private Cloud (VPC) provided network isolation and secure communication between services. AWS CloudFront combined with Amazon S3 was used to deliver static content with low latency and high availability.

Application runtime and orchestration: AWS ECS Fargate

The back-end services were deployed using AWS ECS Fargate, enabling containerized workloads without the need to manage underlying servers. This approach ensured flexible scaling and efficient resource utilization.

Messaging and caching: AWS ElastiCache, Amazon MQ

AWS ElastiCache was used to optimize performance and reduce response times under peak load, while AWS MQ supported reliable message processing between system components.

Database: AWS RDS PostgreSQL

Amazon RDS with PostgreSQL served as the primary relational database, ensuring data consistency, transactional reliability, and secure storage of marketplace and user data.

NFT storage: Arweave

Arweave was used for permanent, decentralized storage of NFT assets, ensuring long-term availability and integrity of digital content.

Front-end and back-end technologies: React, Python

React was used to build a responsive and interactive user interface, while Python powered the back-end logic, APIs, and business processes.

Payments and compliance integrations:

The platform was integrated with Circle for in-app payments and wallet funding, ACH and Wire transfers for withdrawals, and ONfido for KYC verification to meet U.S. regulatory requirements.

Results

The LeverX—Emerline team delivered a fully functional NFT marketplace that aligned with the client's business vision and regulatory requirements. The platform provided a stable foundation for launching NFT sales and supporting secondary market trading within a single ecosystem.

Both end users and administrators gained access to an intuitive, well-structured interface. Thoughtful UI and UX design, combined with animated NFT drop unpacking, improved transparency and clarity of the purchasing process while making interactions with digital assets more engaging.

The solution was developed in compliance with applicable federal and state regulations in the regions where the client operates, allowing the marketplace to function as a legally sound and scalable product ready for further growth.