Kaustav Chakraborty, Developer in Kolkata, West Bengal, India
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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.


Scarselli Diamonds Inc
Blockchain, Software Architecture, Technical Leadership, Decentralized Systems...
Freelance Client
Hardhat, TypeScript, JavaScript, Games
Enter Slate LLC
Solidity, Ethereum, Blockchain, Non-fungible Tokens (NFT), Cryptocurrency...




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

2023 - PRESENT
Scarselli Diamonds Inc
  • Created a 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 ERC721 NFT contract for diamond registration to establish authenticity on the source and manufacturing of diamonds. Created a composable NFT (ERC998) based on ERC721 for jewelry or fashion watches that used more than one diamond.
  • 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 CloudFormation scripts using a serverless framework.
Technologies: Blockchain, Software Architecture, Technical Leadership, Decentralized Systems, Technical Requirements, Non-fungible Tokens (NFT), Architecture, Estimations, Serverless Framework, AWS Lambda, Amazon API Gateway, PostgreSQL, Amazon S3 (AWS S3), Amazon CloudFront CDN, AWS CloudFormation, TypeScript, Node.js, InversifyJS, TypeORM, Advisory, Back-end Development, React, Next.js, Front-end, Serverless

Smart Contract Auditor

2023 - 2023
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.
Technologies: Hardhat, TypeScript, JavaScript, Games

Solidity Developer for Custom Ethereum Contracts and Mint

2022 - 2022
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.
Technologies: Solidity, Ethereum, Blockchain, Non-fungible Tokens (NFT), Cryptocurrency, Ethereum Smart Contracts, Smart Contracts, Blockchain Platforms, Composable NFT (CNFT), Node.js, APIs, JavaScript, React, HD Wallets, AlchemyAPI, Cryptocurrency Wallets, Web3.js, Ethers.js, MetaMask, PostgreSQL, WalletConnect, Software Architecture, Web 3.0, Full-stack, Express.js, ERC-1155, Back-end Development, Full-stack Development

Tokenomics Advisor

2022 - 2022
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.
Technologies: Blockchain, Tokenomics, Cryptocurrency, Finance, Cash Flow Modeling, Social Networks, ERC-20, Tokenization, Advisory

Blockchain Developer

2022 - 2022
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.
Technologies: Blockchain, Smart Contracts, Ethereum Smart Contracts, Tezos, Decentralized Finance (DeFi)

Solidity Developer for Cryptocurrency Platform

2022 - 2022
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.
Technologies: Blockchain, Solidity, BNB Smart Chain, Binance API, Decentralized Finance (DeFi), PancakeSwap, Hardhat, Cross-currency Swaps, Software Architecture, Web 3.0, ERC-20

Solidity Developer for Enhancing Smart Contracts

2022 - 2022
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.
Technologies: Solidity, Blockchain, Binance API, Decentralized Finance (DeFi), Hardhat, Mocha, Digital Payments, ERC-20

Solidity Smart Contract Developer

2022 - 2022
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.
Technologies: Solidity, Ethereum, Blockchain, Ethereum Smart Contracts, DApps, Alchemy, React, OpenSea, OpenZeppelin, Mocha, Hardhat, ERC-721

Technical Project Lead

2021 - 2022
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.
Technologies: Blockchain, Cross-platform, Crypto, Mobile Apps, Blockchain & Cryptocurrency, Decentralized Exchanges (DEXs), Web 3.0, ERC-20, ERC-1155, ERC-721, Twilio, Tokenization

Portfolio Manager | Enterprise Architect

2021 - 2022
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.
Technologies: Apache Kafka, Java, Spring Boot, Workflow, ELK (Elastic Stack), Jenkins, Apache Maven, Kubernetes, Azure, Single Sign-on (SSO)

Senior Blockchain Engineer

2021 - 2021
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.
Technologies: Solidity, TypeScript, APIs, Software Architecture, Truffle, Hardhat, Blockchain & Cryptocurrency, Decentralized Exchanges (DEXs), ERC-20

Senior Architect | Technology

2009 - 2021
  • Developed, designed, 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.
  • Developed an Application to Extract Sentences from Images & 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.
Technologies: Java, JEE, Amazon Web Services (AWS), Azure, Ethereum, Quorum, Hyperledger Fabric, Hyperledger Indy, Go, Scala, Akka, Apache Kafka, Microservices, Spring, Spring Boot, C++11, HashiCorp, Salesforce, Oracle OEM 12c, JSON Web Tokens (JWT), OAuth, JMS, ActiveMQ, JProfiler, ELK (Elastic Stack), Prometheus, Grafana, Docker, Docker Compose, Kubernetes, Bison, Flex, Digital Asset Management, Solution Architecture, Enterprise Architecture, Verifiable Credentials, Decentralized Identity (DCI), Git, Jenkins, Stanford NLP, C++, Hyperledger, Blockchain as a Service, Back-end Development, Full-stack Development

IT Analyst

2006 - 2009
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.
Technologies: Java, JEE, IBM WebSphere, Enterprise Java Beans (EJB), Apache Struts, Jakarta Server Pages (JSP), Servlet, Spring, XSLT, JAXB, Stored Procedure, Oracle, XML, ZK, Zuul, jBPM

Software Engineer

2002 - 2006
  • 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.
Technologies: Java, PowerBuilder, Mainframe, MVS, COBOL, JCL, Oracle, IBM Db2, Apache Tomcat, Jakarta Server Pages (JSP), Servlet

Modernization of Policy Administration System of Large Financial Company

This project aimed to modernize a large USA-based global insurance company's existing mainframe-based policy administration system using microservices architecture in Azure cloud infra. The project used IBM business process management as a business workflow system and the mainframe as the primary data source. The rest proxy services on the mainframe were built to source data for the business process management workflow through microservice-based choreography. The project has multiple integrations with IBM MQ, IBM Content Manager, and various in-house legacy systems.

• 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

Built a SaaS-based multitenant platform product using microservices in Azure, creating a blockchain-based interoperable platform for the biggest logistics company of CE and its customers' network. As the ideating architect of the product, I helped the customer set up blockchain COE. Built future digital roadmap to standardize the heterogeneous communications with customers, to create shipment transparency, automated order processing, integrated operational processes between cargo and multi-modal carriers, conformance testing, mitigate regulatory compliance, reconciliation, and real-time financial settlement. This product can transact using VC on did and can interoperate using blockchain platforms like Quorum and Fabric. The client SDK built for the platform makes it easy to integrate the platform into all different entities or organizations.

• Architecting, designing, coding, and testing the product.
• Development and POC of VC and DID-based multi-blockchain interoperable platform.
• Winning ARB approval in setting up blockchain COE.
• Participated in CTO and CIO-level discussions.
• Building integration strategy with legacy applications.
• Onboarding of entities and automated deployment of multiple entities.

Citizen Vault Using Decentralized Identity for Middle Eastern Country

Conceptualization and development of microservice and blockchain-based citizen vault for one of the big countries in the Middle East, building a customized decentralized identity based on an Ethereum platform solution. The solution was used to integrate with other government services to identify citizens and store issued credentials of citizens by different government and private agencies.

• 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

This project is to design and create a big financial network based on blockchain, microservices architecture, and data sharing through blockchain between multiple banks across geography within a big consortium to replace the current Swift messaging system with the new microservice-based backbone.

• 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

Various digital technologies evolved with the time that needed research, optimum usability, and performance evaluations. Also, so many new blockchain platforms have evolved since the year 2017. This was an accelerator within the organization to evaluate and explore the features and performance of various new technologies to build capability for the practice. It includes appraising the latest technologies to the customers and promoting them in various business development activities.

• 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

This project is to define a new smart contract language that is inspired by the Scala syntax and compiles to the Ethereum virtual machine fork. This project required full compiler development and testing.

• 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

This was to do POC for natural language processing using neural networks to scan receipts and various other banking business documents and to summarize data from there to feed into the database for reporting.

• 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

This project entailed developing and enhancing the internet payment gateway for the European wing of one of the large USA-based payment processing companies (acquirer). This engagement was for their business growth in EMEA, APAC, and LA regions. I mainly worked with Germany, India, and Australia initiatives to provide architectural solutions and provide technical consultancy to roll out IPG all across EMEA, APAC, and LA regions with needed features demanded by that region's businesses. We implemented a new architecture and design to modernize the internet payment gateway using scalable microservice-based products to cater to more load with automated deployment needs to cope with increasing traffic load.

• 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

This project is mainly to design and develop a centralized lightweight common highly configurable application framework composed of both Oracle and open-source technologies for a large financial company in the USA. All business applications across BUs in the organization were planned to be converted or developed using a custom-made Atom framework. Another big part of this engagement was to design and develop configurable security authorization and entitlement solutions. Oracle Entitlements Server was used in controlled-pull mode as an entitlement solution which was integrated with Atom framework using Spring Security.

• 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

This is a Salesforce integration project to automatically share customer data to a third-party brokerage account opening system. This engagement has two parts—migration of billions of customer data from the legacy Sybase database to Salesforce using SFDC data loader API and integrating multiple web applications with the Salesforce platform. For web security two-way SSL, SAML is used with SOAP-based web services.

• 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)

Travelport is a leading provider of the global travel industry. They are the owner of three major GDS systems in the world, Galileo, Worldspan, and Apollo. This project was meant to develop a configurable universal API product that can integrate all GDS of the globe and act as a universal travel platform. The core part of this project is to develop a web service-based middle layer that will expose various transactional services to any front-end apps like Orbitz and Makemytrip. Also, the project gives provision to create any customized agency and all its sub-layers like a branch, branch group, agent, account, account group, and traveler.

• 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

This project was to build a new web-based 1Stop internet-facing car insurance application to modernize customer legacy mainframe-based applications. It involved creating and maintaining policy administration (PAS), billing and accounts receivable (BNR), document generation (DMS), customer information system (CIS), commissioning system (CMS) applications. Another part of the project was to build an external-facing internet application and middle layer service framework to consume the core 1Stop functionalities.

• 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

Involved in multiple projects in SCE engagement. Initially, I engaged in PowerBuilder migration of CSS application after that contributed to the development, enhancement, and support of core business app (CSS), call center app (CWO), and meter process automation (MPA) applications. Involved in the modernization of applications using java oracle stack.

• 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

The product was built and expanded on otbTRADE and it is essentially a decentralized ERC20 and BEP20 cryptocurrency exchange that combines the best of the traditional order book approach with a liquidity provider approach (Pancakeswap) where the users can trade and manage their assets efficiently on one platform. The platform also includes a lottery system for investors to increase gains.

• 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

Developed a gas-optimized efficient NFT for Ethereum main net compatible with OpenSea and Rarible royalty payment.

• 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

Developed a decentralized finance platform like DRIP Network that enables buying on presale, whitelist, and public presale. When the after-sales start, the presale token can be swapped for a sale token. A sale token could be staked to get interest and sold to get BUSD after swapping through PancakeSwap. Tax on tokens is also supported for any transfer.

• 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

Orsy is a new platform being built for citizen journalists or any average person to be able to upload streaming news coverage worldwide through their mobile phone. Once uploaded, based on the number of views and likes, journalists are compensated with a token called Orsy. Any viewer can choose to tip the news uploader, and any news agency can decide to hire Orsy platform journalists in an uberized manner.

• 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

This project was meant to create a platform based on the Tezos blockchain to pledge game development to the developers. Based on an individual's pledge, an NFT is awarded the pledge certificate. It also enlists the Born token into Tezos DEX.

• 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 Rematic Token (RMTX) created the Rematic V1 token using the PinkSale anti-bot token platform. It allowed the staking of RMTX tokens by their community and automatically distributed dividends using EGC (Evergrow coin). Users used to invest in RMTX through BUSD and PancakeSwap and get an EGC coin as a dividend, which they converted to BUSD through PancakeSwap in the BSC chain. The PinkSale anti-bot smart contract is directly integrated with PancakeSwap and generates auto dividend distribution logic.

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.

• 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

Valuit is a decentralized finance platform that allows users to launch and trade assets and licensed securities tokens in a decentralized manner. The main objective of the Valuit product is to promote the use of blockchain to allow for transparency and efficiency when trading and offering asset tokens and securities. This project launched its ICO for VALU tokens and created a DAO platform through which investors or corporations could take loans in place of securities. It also facilitated projects to launch their own ICO and tokens, finance their projects, and collect dividends from project gains. All in a completely transparent autonomous way with community voting. It also creates its DEX for Valuit-launched platform tokens and project-specific tokens.

• 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

This project primarily involved creating a back-end system with composable NFT (ERC998) with multiple child NFTs and bidding token NFT. The project wants to implement a 3D citizen NFT which can hold multiple children NFTs Like Body, District, multiple Wearables, etc., to define a character for AR and VR applications.

• 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

This project was to do a functional and security audit of smart contracts for a new DEX (fork of uniswap) for a financial company and create web3 onramp application development.
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


Java, Solidity, GraphQL, C++11, JavaScript, Go, Scala, PowerBuilder, COBOL, XSLT, Stored Procedure, XML, XSD, Python, Apex, SAML, WADL, TypeScript, C++


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, Tendermint, JUnit, Serverless Framework, Next.js


Node.js, REST APIs, Web3.js, React, JAXB, JMS, Jenkins Pipeline, TensorFlow, Stanford NLP, JAX-WS, Chai, Binance API, OpenNLP, InversifyJS


Mocha, Amazon Elastic Container Service (Amazon 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), MS Exchange, Amazon CloudFront CDN, AWS CloudFormation


Microservices Architecture, Microservices, Serverless Architecture, DevOps, Cross-platform


Ethereum, Apache Kafka, Amazon Web Services (AWS), Hyperledger Fabric, Kubernetes, Blockchain, Bluetooth LE, Azure, Blockchain Platforms, Linux, Ubuntu, Google Cloud Platform (GCP), Oracle, JEE, IBM WebSphere, Salesforce, Docker, MultiChain, Hedera Hashgraph, JBoss, Azure Event Hubs, Twilio, AWS Lambda, Hyperledger


Database Architecture, DB, MySQL, Cassandra, MongoDB, MVS, IBM Db2, MySQL Clustering, Sybase, PostgreSQL, Amazon S3 (AWS S3)


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), GraphDB, Electronics, Instrumentation, Software, Data Structures, Mathematics, Physics, Computer Science, Mainframe, Enterprise Java Beans (EJB), Oracle OEM 12c, OAuth, Prometheus, Bison, Digital Asset Management, Verifiable Credentials, Workflow, Single Sign-on (SSO), Spring Cloud, Decentralized Systems, Streaming, Zeebe, IPLD, WebLogic, Coherence, IPFS, Waffle, Non-fungible Tokens (NFT), OpenZeppelin, Hardhat, PancakeSwap, OpenSea, IT Security, Big Data, Ethereum Smart Contracts, Decentralized Finance (DeFi), Tezos, 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, Alchemy, BNB Smart Chain, AlchemyAPI, Social Networks, Cosmos SDK, Blockchain & Cryptocurrency, Decentralized Exchanges (DEXs), 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

1998 - 2002

Bachelor of Engineering Degree in Electronics and Instrumentation

Vidyasagar University - West Bengal, India


Certified Blockchain Developer

Blockchain Council


Certified Blockchain Expert

Blockchain Council

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