What were the biggest technical challenges you faced while building high-concurrency payment systems?
In building DCpay, we faced a core challenge—how to achieve high-concurrency payment processing under both decentralized and centralized system architectures. Traditional centralized payment systems, such as Visa, Mastercard, and Alipay, can easily handle hundreds of thousands of TPS (transactions per second), but the throughput of blockchain payments is usually low. How to make the two compatible and maintain high availability, high security, and high scalability has become a difficult problem for our team to overcome.
How did you ensure the security and stability of your cryptocurrency trading systems?
In the process of building DCpay, security and stability have always been our core concerns. Compared with traditional financial systems, cryptocurrency trading systems face more security threats, such as private key leakage, smart contract vulnerabilities, transaction risks, DDoS attacks, transaction manipulation, etc. Due to the irreversibility of blockchain transactions, once a security vulnerability occurs, it often causes irreparable losses.
In order to ensure the security and stability of the DCpay transaction system, we have made a lot of optimizations in terms of architecture design, risk control system, infrastructure security, and compliance management.
Can you explain the key differences between the payment systems you developed in Shenzhen and Hong Kong?
The Shenzhen company in China develops a centralized fiat currency payment system, such as Visa, Master, and Swift. The Hong Kong company has developed a cryptocurrency payment system that supports multiple chains, such as Bitcoin and Ethereum.
What strategies did you use to optimize transaction processing speeds?
During the development of the DCpay system, we deeply realized the biggest challenge of the decentralized payment system – how to achieve high concurrency and ultimate user experience while ensuring security. The traditional public chain TPS is limited, and transactions need to wait for block confirmation, resulting in a payment experience that is far inferior to the centralized payment system. Therefore, we combined the Layer 2 solution (Rollup + state channel) and the hybrid payment architecture to successfully solve this problem.
- Layer 2 Solution (Rollup + State Channel)
Through zk-Rollup and Optimistic Rollup, we process most transactions off-chain and submit them to the chain in batches, thereby increasing TPS to 100,000+ and significantly reducing Gas fees. At the same time, the State Channel allows users to complete instant transactions off-chain, and only the settlement results are finally uploaded to the chain, reducing the payment speed from minutes to milliseconds.
- Hybrid Payment Architecture (Combination of Centralization + Decentralization)
We have adopted a model of fast off-chain processing + final on-chain settlement. Users’ transactions are first recorded by a centralized database and then synchronized to the blockchain regularly. This means that users do not need to wait for block confirmation to enjoy the same smooth experience as traditional payments. At the same time, combined with a programmable wallet (Smart Wallet), users’ transactions can be directly executed after off-chain verification, reducing on-chain interactions and further optimizing payment efficiency.
Through Layer 2 + hybrid payment architecture, we have successfully made the speed and experience of blockchain payments comparable to traditional financial systems, while retaining the transparency and security of decentralization. In the future, as Layer 2 technology continues to mature, this architecture will become the standard solution for high-concurrency payment systems, pushing blockchain to truly enter the mainstream payment market.
How do you approach scalability when designing payment and trading systems?
DCpay’s scalability design: a combination of decentralized cryptocurrency + centralized fiat currency system
In the practice of DCpay, we deeply understand that the scalability of payment and transaction systems is a key factor affecting user experience and business growth. Traditional blockchain systems are limited by low TPS (transaction throughput) and high gas fees, while traditional centralized payment systems are efficient but lack transparency and anti-censorship. To take into account the advantages of both, we adopted hybrid scalability architecture to achieve high concurrency capabilities of cryptocurrency and fiat currency payment systems.
- Layer 2 technology: Expand decentralized payments. In the encrypted payment part, we use Layer 2 solutions (Rollup + state channels) to ensure decentralization while improving transaction efficiency.
- Centralized fiat currency system: optimize concurrency capabilities. In the fiat payment part, we use high-performance databases and payment gateways to ensure stability and low latency of large-scale transactions.
What role did product managers play in your projects, and how did you collaborate with them?
In the construction of DCpay, product managers (PMs) play a vital role. They are not only responsible for defining the product direction but also build a bridge between technology and business to ensure that the payment system we build not only meets market needs but also has high performance and security.
In actual cooperation, we have formed a close two-way interaction with PMs. Product managers are not only the demand side, but also strategic partners of the technical team. They ensure that the product meets market needs, while we ensure that the technical solutions are implemented efficiently. Only when technology and products are closely integrated can we truly create a high-performance and easy-to-use payment system.
Can you share an example of a critical operational challenge you faced and how you resolved it?
In the operation of DCpay, an important operational challenge we encountered was compliance issues related to cross-border payments and fiat currency settlement. Since our payment system needs to support multiple fiat and cryptocurrency payments, this involves regulatory policies in different countries and regions, especially in terms of compliance requirements and the implementation of anti-money laundering (AML).
Challenge Analysis:
Differences in regulations in different countries: We are expanding globally, especially in the European, American, and Asian markets, and each country has different compliance requirements for cryptocurrency payments and fiat currency exchanges. The compliance challenges of cross-border payments require us to constantly adjust our operational strategies to ensure compliance with local legal requirements.
AML and KYC regulations: According to the requirements of national laws, anti-money laundering (AML) and know-your-customer (KYC) regulations also vary significantly in different regions. Especially when dealing with fiat currency transfers and cryptocurrency exchanges, the system needs to be able to efficiently handle many compliance audits while ensuring that the user experience is not affected.
Delays in payment settlement: There are differences in liquidity and payment settlement between fiat and cryptocurrency, which is particularly prominent in cross-border payments. Our system needs to ensure timely payment and settlement services in multiple countries and regions while addressing foreign exchange fluctuations and handling fees.
In operations, compliance is always a core challenge for cross-border payments and fiat currency settlements.
What emerging trends in payment systems and cryptocurrency trading excite you the most?
- Seamless integration of digital currency and fiat currency
As central banks around the world pay more and more attention to digital currencies (CBDC), I believe that the integration of digital currency and fiat currency will be an important trend in the future of payment systems. For example, we are exploring how to seamlessly integrate fiat payments with cryptocurrency payments. In the DCpay system, users can use the DCpay APP to quickly exchange and pay between fiat and cryptocurrency. This combination not only improves the payment speed but also enhances the stability of the system.
- Integration of decentralized finance (DeFi)
Decentralized finance (DeFi) has shown great potential, and I am looking forward to the combination of DeFi and traditional payment systems. Through the DeFi protocol, users can not only borrow, lend and trade without intermediaries, but also achieve lower-cost asset exchange and cross-border payments through liquidity pools or decentralized exchanges (DEX). DCpay is exploring the combination of DeFi and traditional payment channels to benefit more users.
- Application of artificial intelligence and machine learning
With the development of artificial intelligence and machine learning technologies, payment systems and cryptocurrency transactions will become more intelligent. The application of AI in risk control, anti-fraud, transaction prediction, and other fields will greatly improve the security and efficiency of transactions. Through real-time monitoring and data analysis, the system can automatically identify potential risk behaviors, warn and prevent them in advance, and provide users with a safer and more convenient payment experience.
How do you balance innovation with regulatory compliance in the financial tech industry?
In the field of fintech, innovation and compliance always have a delicate balance. Especially in high-tech fields such as blockchain technology and cryptocurrency payments, how to promote technological progress while ensuring compliance with the requirements of financial supervision in various countries has always been a key challenge for me and my team in the DCpay project.
At the same time, the balance between innovation and compliance is a continuous challenge, but it is also the key to success. Through compliance-first architecture design, the application of automated compliance tools, cooperation with regulators, and flexible response mechanisms, we ensure that DCpay always complies with the laws and regulations of various countries while promoting technological progress. Real innovation is to promote the continuous optimization of technology and products within the compliance framework and continuously improve user experience and industry efficiency.
What advice would you give to engineers looking to build large-scale financial systems?
During the development of the DCpay system, I deeply realized the complexity of building large-scale financial systems. Financial systems not only need to handle high concurrency, large transactions, and complex business logic but also must ensure stability, security, and compliance of the system. The following are a few suggestions I have summarized from years of technical practice, hoping to provide some inspiration for engineers who are building large-scale financial systems.
- High availability and disaster recovery mechanisms must be the core of the design.
- Scalability and performance optimization cannot be ignored.
- Security is the top priority of system design.
- Design compliant transaction processes and audit functions.
- Focus on users and optimize user experience.
- Establish a monitoring and early warning system.
- Continuous learning and innovation.
In the process of building large-scale financial systems, technological innovation is necessary, but stability, scalability, security, and compliance are always the core requirements. Through high-availability architecture design, performance optimization, security protection, compliance auditing, and user-centered design thinking, we can build a system that is both innovative and can cope with high concurrency and large-scale transactions. At the same time, continuous learning and technological iteration are the keys to ensuring that the system is continuously optimized and adapted to market needs.
We hope that these experiences can help engineers who are developing financial systems avoid detours, respond quickly to industry challenges, and achieve a more efficient, secure, and compliant technical architecture.
