Building Polarys Swap Engine: the first Fiat on-ramp into Ethereum Layer 2, Metis network

Product Shop
4 min readApr 7


Polarys (now Sprynt) is a launchpad for utility-based NFTs that aims to simplify the process of crypto adoption for businesses and users. The platform provides an end-to-end solution for NFTs, including onboarding, reward, and invoice management. Polarys enables businesses, creators, and entrepreneurs to raise funds and engage with users through rewards-based NFTs, without requiring any crypto or coding experience.

To facilitate the onboarding process on the Andromeda blockchain (Ethereum L2), Polarys partnered with ProductShop to build a swap engine where customers can pay with their credit card to obtain $Metis token.

This case study will focus on the technical implementation of regulatory requirements, including KYC flow for first-time users, record of all transactions, and user profiles in a centralized database. Polarys is committed to providing traditional businesses and users with a trusted, easy-to-use platform focused on utility NFTs that offer real-life rewards to holders.

Polarys has since rebranded to
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Challenges and Goals of the Swap Engine for Polarys’ Onboarding Process

The swap engine is a crucial component of Polarys’ onboarding process, providing an accessible and user-friendly way for customers to obtain $Metis tokens using their credit card. However, building such a solution presented several challenges, including the need to integrate with a layer 2 network, ensure regulatory compliance, and provide a seamless user experience.

The goal of the swap engine was to simplify the onboarding process, reduce transaction fees and wait times, and increase accessibility for users who are not familiar with the technical aspects of cryptocurrencies. By overcoming these challenges, Polarys has created an innovative and easy-to-use solution that removes the barriers to entry for those who want to participate in the crypto world.

The first Fiat on-ramp into Ethereum Layer 2, Metis network

The Polarys Swap Engine, developed by ProductShop, offers a straightforward and efficient solution for users who want to enter the crypto world through fiat onboarding. The implementation of the swap engine addresses the challenges of traditional onboarding processes by providing a user-friendly and seamless solution.

In order to meet the regulatory requirements, the technical implementation required the integration of several providers, such as Wyre as the payment provider, Blockpass for KYC, and Hera as the protocol for the swap.

The user experience with the swap engine is designed to be smooth and intuitive. To use the swap engine for the first time, users will need to complete a KYC verification process, which is required for regulatory purposes. Once the verification process is complete, users can connect their wallet and input the amount of $METIS tokens they wish to acquire. The next step involves entering their credit card details to make the purchase. The process is straightforward and does not require any prior knowledge of cryptocurrencies or blockchain technology.

However, achieving a seamless experience for users to acquire $METIS tokens through the swap engine required several steps behind the interface. Firstly, the engine accepts deposits in fiat currency, which are then converted to USDC, a stablecoin pegged to the US dollar. Next, the USDC is bridged to the Andromeda Layer 2 network, which is a blockchain optimized for fast and low-cost transactions. Once the USDC is bridged, a swap is performed using HERA, a DEX partner company, resulting in the user receiving Metis L2 tokens in their wallet address. In addition, users have access to their transaction history and can view links on the Andromeda explorer, providing full transparency and record of their transactions.

Ultimately, Polarys Swap Engine removes the complexity and technical barriers that have previously hindered many users from participating in the crypto space and provides a seamless and user-friendly solution that can help to drive the growth and adoption of cryptocurrencies. The implementation of the Swap Engine offers several benefits, including a tightly integrated KYC solution, a seamless onboarding experience, and an interface with transaction history.

Polarys Swap Engine available here:

“We had the pleasure of working with ProductShop for our Swap Engine and must say, their expertise and dedication have been instrumental in bringing our vision to life. The team was able to turn our concept for the first Fiat on-ramp into Ethereum Layer 2 into a reality, and the result is simply impressive”
says Selin Suntay, CEO of Polarys.

The Polarys swap engine developed by ProductShop has made the process of entering the crypto world more accessible and user-friendly. The technical implementation of the swap engine offers a fast, easy, and affordable way to onboard new users, removing the complexity and technical barriers that have previously hindered many users from participating in the crypto space. The seamless user experience provided by the swap engine has resulted in a decrease in the drop-off rate of new users and increased adoption of the Polarys platform.

Overall, the collaboration between Polarys and ProductShop has helped to address the challenges of onboarding new users into the crypto world, driving the growth and adoption of cryptocurrencies.

About ProductShop

ProductShop is a leading Web2 and Web3 development studio, and we’re here to help you bring your project to life. Visit our website or contact us at to learn more about our services and how we can help turn your vision into reality.

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