Kaustav Chakraborty
Verified Expert in Engineering
Blockchain Architect and Cloud Developer
Kolkata, West Bengal, India
Toptal member since October 9, 2021
Kaustav is a hands-on, goal-oriented, versatile technology professional with more than two decades of experience, primarily in open-source digital technologies, such as blockchain, IoT, microservices, cloud, distributed architecture, R&D, design, and development, with a proven track record delivering consistent business results. He loves to take on technical challenges, learn about new technology innovations, and deliver successful products worldwide.
Portfolio
Experience
- Java - 18 years
- Ethereum - 6 years
- Spring Boot - 6 years
- Enterprise Architecture - 5 years
- Cloud - 5 years
- Microservices Architecture - 4 years
- Quorum - 3 years
- Hyperledger Fabric - 3 years
Availability
Preferred Environment
Linux, Ubuntu, Amazon Web Services (AWS), Azure, Google Cloud Platform (GCP)
The most amazing...
...things I've developed are an interoperable SaaS platform, a citizen vault using blockchain, and a smart contract language compiler for EVM.
Work Experience
Blockchain Solution Architect (via Toptal)
Scarselli Diamonds Inc
- Created blockchain-based diamond asset registration and authenticity of diamonds. Established the provenance of diamonds from the mine to the end user. Involved in defining the end-to-end design and architecture, along with ideation.
- Created an ERC-721 NFT contract for diamond registration to establish the authenticity of the source and manufacturing of diamonds. Created a composable NFT (ERC-998) based on ERC-721 for jewelry or fashion watches that used more than one diamond.
- Worked on tokenizing the assets and then trading the tokens into secondary markets. Developed contracts for the fractionalization of assets using ERC-20 and transferring the asset into a vault contract.
- Made a serverless API based on Node.js and TypeScript in AWS for asset registration, diamond finder, marketplaces, etc.
- Developed all environments in AWS with a fully automated CI/CD pipeline based on GitHub Actions and AWS CloudFormation scripts using a serverless framework.
Blockchain Developer
T47 Group LLC
- Built a trading platform on sports with governance guaranteed through private blockchain (probably for the 1st time).
- Developed a sports trading app backed by Hyperledger Fabric, deployed in a Kubernetes cluster via an automated CI/CD pipeline.
- Integrated a plug-and-play 3rd-party sports API to fetch games, leagues, teams, schedules, and score data.
Smart Contract Auditor
Freelance Client
- Audited DEX smart contracts using slither scan and manual test scripts.
- Created reports including code scanning summary, inheritance graph analysis, function call graph analysis, data dependencies analysis, constructor calls, storage order and slots, security checks, etc.
- Wrote unit test cases and manually tested edge cases and large-value ether transfers.
Solidity Developer for Custom Ethereum Contracts and Mint
Enter Slate LLC
- Performed requirement analysis and designed data structure segregating on-chain and off-chain qualifications.
- Designed and developed a composable 3D NFT (ERC998-ERC1155 top-down) with an animated composable image in OpenSea.
- Created and developed Node.js, Inverse.js, and a Web3-based back-end API application with PostgreSQL as an off-chain database.
- Built a React front-end application with Web3 integration to demonstrate end-to-end platform implementation.
- Developed and integrated with multiple wallets like MetaMask, Trust Wallet, Coinbase Wallet, and Gnosis Safe wallet.
- Deployed the front-end POC and back-end API applications into AWS EC2 and smart contracts into Goerli testnet through scripts.
Tokenomics Advisor
Orsy Inc.
- Advised the client on creating token economics through blockchain within the platform independently based on the supply and demand of the assets and services.
- Designed the tokenization of media assets, a financial model, cash circulation, and inflationary scenarios for the ORSY utility token, envisioning real-world business data predictions.
- Assisted the product manager and client in streamlining ways to generate revenue and advised for initial investments for the platform token to achieve predicted results with example scenarios.
- Managed the blockchain developers with the contract design and suggested developing hooks for the platform owner to control cash flow and dividends.
Blockchain Developer
Block Born LLC
- Conceptualized and designed from the initial phases of the project to introduce Tezos blockchain into the BlockBorn platform.
- Engaged in a crowdfunding marketplace. Handled R&D in the Tezos blockchain platform resources and used it to develop a system.
- Developed Tezos FA1.2 and FA2 standards tokens for BlockBorn and created NFT certificate tokens for pledging into games.
- Enabled and helped a full-stack developer integrate the Tezos blockchain into dApp with temple wallet integration.
Solidity Developer for Cryptocurrency Platform
Preston Scheidt
- Developed multiple token smart contracts, including PSLDR, SLDR, and Future Token.
- Developed staking and taxing smart contracts for the game.
- Helped a front-end developer with various React codes to enable Web3 integration and connect with blockchain.
- Integrated with PancakeSwap for automated SLDR to BUSD exchanges and conducted manual and automated testing.
Solidity Developer for Enhancing Smart Contracts
Rematic Tokens LLC
- Analyzed, tested, and identified the leakages and performance bottlenecks in the RMTX v1 smart contract.
- Proposed an alternate solution for making dividend distribution efficient instead of using existing EGC coins through direct swap through PancakeSwap.
- Conducted the security audit of the PinkSale-generated V2 contract. Tested the v2 smart contract using an automated test suit.
Solidity Smart Contract Developer
BRD Ventures LLC.
- Developed a gas-optimized efficient NFT for the Ethereum main net compatible with OpenSea and the Rarible royalty payment. It had multiple private sale phases prior to the public sale.
- Assisted with the React front-end app, integrating it with smart contracts with Web3 and MetaMask integration.
- Deployed all smart contracts into the main net and decentralized applications into the cloud.
Technical Project Lead
Valuit LLC
- Provided initial guidance, analyzed the business requirements to shape the blockchain adoption, and converted the end-to-end technical requirements for smart contracts and front- and back-end applications.
- Utilized blockchain and mobile application expertise. Assisted the client in choosing the right blockchain platform for their use case.
- Developed smart contracts for VALU tokens and crowdsaling contracts for the ICO.
- Designed and developed upgradable smart contracts to implement the platform ecosystem for security tokens, including ERC2535, 1400, 1410, 1594, 1643, 1644, voting, and DEX.
- Performed the tokenization of assets of community members based on the accessed asset values of their company and provided loans by platform with their assets as securities.
Portfolio Manager | Enterprise Architect
Capgemini India
- Developed and designed digital distributed architecture for the policy administration system of a large, global financial company.
- Created a framework with the latest technologies based on customer choice.
- Mentored a team of professionals to quickly develop with the latest digital technologies on Azure using cloud-native solutions.
- Built and reviewed workflow solutions, integrating with the mainframe-based Life-Asia system.
Senior Blockchain Engineer
OTBDev Corp
- Created a fork of PancakeSwap to build OTBSwap smart contracts and made an OTBC token smart contract.
- Designed and developed a smart contract for the order book DEX and combined it with PancakeSwap.
- Conducted the smart contract development for the lottery system for the OTB trade DEX ecosystem.
Senior Architect | Technology
Cognizant
- Developed, designed, and defined architecture in building an interoperable logistics and supply chain SaaS-based platform for the largest logistics company in Europe using blockchain, microservices, and decentralized identity with verifiable credentials.
- Developed and created a framework for citizen vault for a Middle Eastern country using decentralized identity in generalized blockchain platforms like Quorum and Hyperledger Fabric.
- Participated in R&D activity of various blockchain platforms along with exploration and performance evaluation of various new technologies and platform solutions.
- Developed and designed a new smart contract language (full compiler) inspired by the Scala syntax and compiles it to the Ethereum virtual machine fork.
- Created an application to extract sentences from images and documents using natural language processing.
- Developed an internet payment gateway for the European wing of a large USA-based payment processing company (acquirer). Proposed modern architecture and design using scalable microservice-based products to cater more load with automated deployment.
- Designed and developed a centralized lightweight common configurable (Atom) application framework using Spring Boot for a large USA financial company. Developed configurable security entitlement solution using Oracle Entitlements Server.
- Migrated customer data from legacy Sybase database to Salesforce for a large brokerage company in the USA. Integrated multiple web applications with the Salesforce platform.
- Developed uAPI middleware for the travel industry integrating world three major GDS like Galileo, Worldspan, and Apollo.
- Worked in DevOps and project management automation using Atlassian tech stacks, including Jira administration, Jira REST API, and Jira Java client.
IT Analyst
Tata Consultancy Services
- Developed and maintained billing and receivable and policy administration platform for the largest Insurance company in the USA of that time. Product was developed for the auto insurance business to replace their legacy mainframe-based application.
- Developed and maintained policy administration (PAS), billing and accounts receivable (BNR), document generation (DMS), customer information system (CIS), and commissioning system (CMS) applications. Used CVS for version control.
- Developed and maintained external-facing internet application and middle layer service framework to consume the above-mentioned core 1Stop functionalities. Used CVS for version control. Used customer propriety tool to manage defects.
- Contributed primarily to requirement analysis, coding, and unit testing. Participated actively in SIT testing, UAT testing being at the onshore location. Played primary customer-facing role for billing and receivables module.
- Developed and involved in R&D to build workflow-based modern application framework using Spring, jBPM, ZK, Zuul for one of the large insurance brokers and risk advisors in the UK.
Software Engineer
Infosys
- Developed and maintained a meter process automation application for Southern California Edison using PowerBuilder, which interacted with mainframe procedures written in COBOL through RPC. Written COBOL routines and JCL jobs. Executed manual testing.
- Developed and maintained a customer service application (CWO) and core business app (CSS) for Southern California Edison using PowerBuilder. Developed COBOL routines as part of the work, executed manual testing, and tracked bugs in Bugzilla.
- Developed and maintained the upgrade of legacy applications in Java with Oracle DB.
- Contributed to coding, unit testing, requirement analysis, performance testing, and change impact analysis. Provided operational support and engaged in onshore-offshore coordination, customer handling, and production support.
Experience
Modernization of Policy Administration System of Large Financial Company
ENGAGEMENTS
• Building, architecting, designing, and testing the product
• Customer orientation, the conceptualization of digital designs, and architecture
• Product feature prioritization
• Building initial framework to make the large volume deliverables through few developers without much technical challenge
• Product roadmap and plan creation
• Building integration strategy with legacy applications
• Product go-live roadmap
• Building CI/CD automated DevOps pipeline
Logistics and Supply Chain Platform for Largest Logistics Company in Europe
ENGAGEMENTS
• Architected, designed, coded, and tested the product.
• Developed a POC of VC and DID-based multi-blockchain interoperable platform.
• Won ARB approval to set up blockchain COE.
• Participated in CTO and CIO-level discussions.
• Built an integration strategy with legacy applications.
• Onboarded entities and automated deployment of multiple entities.
Citizen Vault Using Decentralized Identity for Middle Eastern Country
ENGAGEMENTS
• Building framework and POC.
• Conceptualizing, creating architecture, coding, and testing DID-based ecosystem with a general blockchain platform.
• Defining microservice-based architecture; kickstarting the project; multiple entity onboarding strategies.
• Participating in customer discussions, requirement gathering, and technology consulting.
Interbank Information Network for Big Financial Consortium
ENGAGEMENTS
• Designing and development of the initial framework.
• Designing a blockchain-based system.
• Channelization into large-scale development.
• Moving the initial AWS hosting into the private cloud.
• Code review, quality monitoring, security analysis, and performance analysis.
Exploration and Performance Evaluation of Various Digital Technologies and Platform Solutions
ENGAGEMENTS
• Exploration and evaluation of features of various digital technologies, including blockchain platforms.
• Development of accelerator frameworks and reusable codes for fast usage of new digital software and platforms.
• Creation of a custom-made decentralized identity (DID) solution.
• Performance analysis of various software and platforms.
• Gap analysis and platform fitment analysis.
• Building POC applications to explore platform features.
Compiler Design and Development for Smart Contract Language for EVM Fork
ENGAGEMENTS
• Analysis and envisioning of Ethereum EVM-supported opcodes.
• Designing and developing grammar and parser using Bison and Flex.
• Designing and developing AST and semantic analyzer.
• Designing codegen and datagen visitors.
• Designing and developing test harness using Go.
• Testing and leading a team.
POC Application to Extract Sentences from Images and Documents Using NLP
ENGAGEMENTS
• Self-learning of artificial intelligence and natural language processing.
• Designing and developing using Python to establish machine learning.
• Designing and developing image processing from documents.
Building and Enhancement of Internet Payment Gateway
ENGAGEMENTS
• Understanding client requirements.
• Coding design testing and review.
• Acted as a techno-functional lead of the team and owned all deliveries.
• Knowledge transition, helping and guiding the team to scale up to meet business needs.
• UML, RFE/RFI, technical architecture, and solution design using open stack technologies for various needs of businesses.
• Redesigned and created microservice-based architecture and design with auto-scalable needs within an on-premises data center.
Organization Application Framework for Large Financial Company
ENGAGEMENTS
• Requirement understanding.
• Multiple POC, UML, RFP, solution design, and development.
• Developed and maintained the entitlement module using OES integrated with Spring security.
• Developed multiple tools for POC.
• Collaborated with Oracle support team, upgrades, and implementations.
Salesforce-based Brokerage App for Large Global Financial Company
ENGAGEMENTS
• Requirement analysis and design.
• Designed and developed middle layer architecture to interface between third-party systems and Salesforce for secure data exchange.
• Learning and development in Salesforce using APEX, SOQL, and WADL.
• Data analysis, re-engineering, and data migration using SFDC data loader.
• Third-party connectivity testing, integration testing, and security enablement.
• Provided UAT support.
• Production deployment planning and verification after deployment.
uAPI for Travel Industry (Integrating World GDS)
ENGAGEMENTS
• POC, R&D, technically helping team members to deliver on time.
• Coding, code reviews, peer reviews, and unit testing.
• Development, release planning, defining stories, analysis, planning, and estimation.
• Performance monitoring and analysis issue resolution.
1Stop | Policy Administration Platform for Insurance Company in the USA
Engagements:
• Requirement analysis, use case preparation, coding, and development.
• Prepared unit test, system test, and UAT test plans.
• Onshore and offshore coordination.
• Setting up infrastructure and guidelines for the new maintenance project.
• Worked both as a developer and business analyst of the billing and accounts receivable system.
• Configuration management, problem management, and release management.
• Acted as the leading participant in client coordination and consultation.
• Played the main leading role in UAT planning and UAT execution.
• Provided nightly batch support periodically.
Meter Process Automation and Customer Service App for Distribution Company in Southern California
Engagements:
• Requirement analysis, coding, unit testing, performance testing, and impact analysis.
• Leading modules, guiding team members, and reviewing deliverables.
• Production implementation after every release.
• Operational support.
• Onshore and offshore coordination.
• Change request implementations and production support.
Decentralized Exchange (DEX with Orderbook) and Lottery System—DeFi in BSC Chain
RESPONSIBILITIES
• Smart contract development to create a fork of PancakeSwap
• Smart contract development for order book DEX
• Combining Pancakeswap with Orderbook
• Smart contract development for the lottery system
• Unit test cases using Truffle
• Manual testing
Gas-optimized NFT ERC-721
FEATURES:
• Always mint random tokens.
• Max 5,000 tokens are in supply.
• Each wallet can mint a maximum of 12 tokens.
• Multiple presale periods with configurable starting times before the crowdsale starts.
• Only whitelisted addresses can participate in the presale.
• Mint price is 0.3 Ether per token.
• NFT reveal time is configurable by the owner and revealed after crowdsale started and posted immediately after mint.
• The owner can pause the minting token and stop revealing NFT anytime, even after crowdsale starts.
• 100 tokens are reserved for the owner that can be minted anytime.
• All payments are collected into the contract on mint function.
• Only Ethers are accepted as a payment method.
• The owner can withdraw the fund in the following percent—marketing 3%, community 11%, donations 12%, and the two owners each get 37%.
• Royalty payment of 10% on secondary sale paid to NFT creator.
• Secondary sale in OpenSea.
Crypto Platform Design and Development Powered by PancakeSwap—DeFi
RESPONSIBILITIES:
• Develop multiple token smart contracts
• Develop a staking smart contract
• Built the taxing smart contract
• Integrate with Pancakeswap for automated exchanges of SLDR to BUSD
• Hardhat-based automated test script
• Manual testing
Orsy Platform Tokenomics
MY ROLE:
• Advise the client on how to create token economics through the blockchain within the platform independently based on the supply and demand of the assets and services.
• Develop a financial model using the Orsy utility token with a real-world data model.
• Develop cash circulation and inflationary models envisioning real-world scenarios.
• Help the product manager build the use case in the project.
• Assist the client in streamlining ways to generate revenues in the platform.
• Advise the client with initial and future investments they need based on financial modeling and lay out ways to tackle various inflationary situations in the platform.
• Advise the blockchain developers with the contract design and suggest developing hooks for the platform owner to control cash flow and dividends.
Blockborn - a DeFi Project to Pledge into Games Development
MY ROLE:
• Initial conceptualization and design to introduce Tezos blockchain into the BlockBorn platform.
• R&D in the Tezos blockchain platform resources and use it to develop a system.
• Develop Tezos FA1.2 and FA2 standards tokens for BlockBorn.
• Develop an NFT certificate token for Tezos.
• Create a blockchain workspace with Ithcanet and Tezos Temple Wallet.
• Enlist the BlockBorn token in the Tezos DEX platform.
• Overall blockchain development and testing.
Analysis and Audit of Rematic Token Smart Contracts—DeFi
The generated smart contract had flaws, primarily security and performance issues. A good worth of RMTX tokens was getting leaked because of an error in the PinkSale anti-bot smart contract. The dividend distribution process had a performance bottleneck and used to cause a large amount of loss through gas.
MY ROLE:
• Analyze, test, and identify the leakage and performance bottleneck in the RMTX v1 smart contract.
• Propose an alternate solution for making dividend distribution efficient.
• Help the client build a V2 smart contract through PinkSale.
• Simplify the V2 contract dividend distribution and eliminate the EGC token.
• Security auditing of the V2 contract.
• Generate automated test cases for the V2 contract.
Valuit DeFi Platform for Transparent Securities Trading and Project Funding Using Blockchain
https://valuit.io/MY ROLE:
• Initial guidance and analysis to shape the requirements for blockchain adoption.
• Assist the client in choosing the blockchain platform.
• Develop smart contracts for VALU tokens and crowdsaling contracts for ICO.
• Shape up the requirements for platform application building (front-end and back-end).
• Design and develop upgradable smart contracts to implement the platform ecosystem for security tokens (ERC2535, 1400, 1410, 1594, 1643, 1644), voting, DEX, etc.
Composable NFT Development for 3D Immersive Applications for Virtual Reality
MY ROLE:
• Requirement analysis and segregation in on-chain and off-chain data structure design.
• Composable 3D NFT (ERC998 ERC1155 Topdown) design and development with an animated composable image in OpenSea.
• Node.js, Inverse.js, Web3-based back-end API application design and development with Postgres off-chain database.
• Development of the React front-end application with Web3 integration to demonstrate end-to-end platform implementation.
• Development and integration with multiple wallets like Metamask, Trust Wallet, Coinbase Wallet, and Gnosis Safe wallet.
• Implementation of WalletConnect protocol in the front-end application.
• Deployment of the back-end API application into AWS.
Audit of Smart contracts for DEX
I created reports, including code scanning summary, inheritance graph, function call graph, and data dependencies analyses. I also made constructor calls, storage orders and slots, security checks, etc.
The following checks were done during the security checks:
• Reentrancy
• Upgradability
• Patching to be done based on usage check (Echidna) or remove asserts etc.,
• ERC conformance
• Uninitialized local variables and memory
• Uninitialized Storage variables, Ether Lock, tx.origin
• Low-level ASM
• Unexpected sending of Ether to Arbitrary destinations, unchecked external calls, and leaks
• Pragma Directive
• Overflow and underflow
• Fallback and Receive
• Force-feeding check
• Unsafe Arithmetic
• Short Address
• Dos Attack
• Transaction order dependence, call stack depth, gas limits, and loops, including griefing
-Timestamp dependence, dangerous delegate calls, private information, and randomness
• mapping clearing
-Code patterns, Oracle Manipulation, if any
Global Sports Team Trading Platform with Private Blockchain Integration
http://www.gamechangermarket.comThe platform allows payment deposits and withdrawals through Stripe, and the user gathers pennants (valued at 1 USD each). After getting pennants, users can buy teams. When a team wins, then, based on a blockchain-based immutable algorithm, the price goes up, which is related to the ratio of pennant volumes for the participating teams in a game. The platform has the ability to onboard leagues and teams through the admin portal, and once a game is onboarded, it's available for users to buy and sell.
The schedule and scores of games of any league are fetched from plug-play-based 3rd-party API, and once the scores are published, the system detects who won and lost, and accordingly, blockchain smart contract moves the prices of the teams. The platform also supports a rewards program with five tiers and a referral program. The project's back end is fully governed by a private blockchain Hyperledger Fabric deployed into the AWS cloud in a scalable way.
Education
Bachelor of Engineering Degree in Electronics and Instrumentation
Vidyasagar University - West Bengal, India
Certifications
Certified Blockchain Developer
Blockchain Council
Certified Blockchain Expert
Blockchain Council
Skills
Libraries/APIs
Node.js, REST APIs, Web3.js, React, JAXB, Java Message Service (JMS), Jenkins Pipeline, TensorFlow, Stanford NLP, JAX-WS, Chai, OpenZeppelin, Binance API, OpenNLP, InversifyJS, Jira REST API, Java APIs
Tools
Mocha, Amazon Elastic Container Service (ECS), MetaMask, HashiCorp, JCL, Apache Tomcat, Servlet, Zuul, Hyperledger Indy, ActiveMQ, JProfiler, ELK (Elastic Stack), Grafana, Docker Compose, Git, Jenkins, Apache Maven, IBM BPM, IBM Content Manager, IBM MQ, Ansible, Vault, Amazon EKS, SoapUI, JBoss Drools, JiBX, Azure Kubernetes Service (AKS), Microsoft Exchange, Amazon CloudFront CDN, AWS CloudFormation, Terraform, Helm, Amazon CloudWatch, AWS CloudTrail, Jira, AWS IAM
Languages
Java, Solidity, GraphQL, C++11, JavaScript, Go, Scala, PowerBuilder, COBOL, XSLT, Stored Procedure, XML, XSD, Python, Apex, SAML, WADL, TypeScript, C++, Rust
Frameworks
Spring Boot, Spring, Spring Security, Express.js, Jakarta Server Pages (JSP), Apache Struts, ZK, jBPM, Akka, JSON Web Tokens (JWT), Flex, Apache Struts 2, Hibernate, Spring Integration, Spring Web Flow, JSF, Jersey, iBATIS, Truffle, Hardhat, Alchemy, Tendermint, Cosmos SDK, JUnit, Serverless Framework, Next.js, NestJS
Paradigms
Microservices Architecture, Microservices, Serverless Architecture, DevOps, Cross-platform, Automation
Platforms
Ethereum, Apache Kafka, Amazon Web Services (AWS), Hyperledger Fabric, Kubernetes, Blockchain, Bluetooth Low Energy (LE), Azure, Blockchain Platforms, Linux, Ubuntu, Google Cloud Platform (GCP), Oracle, JEE, IBM WebSphere, Salesforce, Docker, MultiChain, Hedera Hashgraph, JBoss, PancakeSwap, Tezos, AlchemyAPI, Azure Event Hubs, Decentralized Exchanges (DEXs), Twilio, AWS Lambda, Hyperledger, Amazon EC2
Storage
Database Architecture, DB, MySQL, Cassandra, MongoDB, MVS, IBM Db2, MySQL Clustering, Sybase, PostgreSQL, Amazon S3 (AWS S3), Amazon Aurora
Other
Quorum, Distributed Systems, Solution Architecture, Smart Contracts, Fintech, Cryptocurrency, APIs, Cryptocoin Mining, Architecture, Web Security, Tokenomics, CI/CD Pipelines, Internet of Things (IoT), Technical Leadership, Polygon, DApps, Web 3.0, Consulting, Fintech Consultant, Software Development, Decentralized Identity (DCI), Enterprise Architecture, Cloud, Uniswap, Decentralized Autonomous Organizations (DAO), DEXTools, GraphDB, Electronics, Instrumentation, Software, Data Structures, Mathematics, Physics, Computer Science, Mainframe, Enterprise Java Beans (EJB), Oracle OEM 12c, OAuth, Prometheus, Bison, Digital Asset Management, Credentialing, Workflow, Single Sign-on (SSO), Spring Cloud, Decentralized Systems, Streaming, Zeebe, WebLogic, Coherence, IPFS, Waffle, Non-fungible Tokens (NFT), OpenSea, IT Security, Big Data, Ethereum Smart Contracts, Decentralized Finance (DeFi), Finance, Cash Flow Modeling, Exchanges, Cross-currency Swaps, Crypto, Mobile Apps, ERC-1400, Composable NFT (CNFT), HD Wallets, Cryptocurrency Wallets, Ethers.js, WalletConnect, Software Architecture, Digital Payments, BNB Smart Chain, Social Networks, Blockchain & Cryptocurrency, Global Distribution Systems (GDS), SOAP, Full-stack, ERC-1155, ERC-20, ERC-721, Tokenization, ICO, Cryptocurrency Exchanges, Games, Technical Requirements, Estimations, Amazon API Gateway, TypeORM, Web3, Advisory, Blockchain as a Service, Back-end Development, Front-end, Full-stack Development, Serverless, Slate, Jira Administration, Jira Administrator, Third-party Integration, Third-party APIs, Identity & Access Management (IAM), Containers
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