Warren is available for hire
Hire WarrenWarren Schwartz
Verified Expert in Engineering
Software Developer
Dolphin Coast, South Africa
Toptal member since December 28, 2021
Bio
Warren has been in software development for the last 20 years, and he has delivered hundreds of successful projects. In the previous four years as a CTO, he has proudly led a team of five developers to produce some great apps using blockchain and conventional tech.
Portfolio
Lab27
Blockchain, Web3.js, Aurelia, TypeScript, C#.NET, React, Blazor, Node.js...
Shane Richardson
Solidity, Blockchain, JavaScript, Ethereum Smart Contract...
Libertas GH PTY LTD
React, Web3.js, Node.js, Smart Contracts, Truffle
Experience
Availability
Part-time
Preferred Environment
WhatsApp, Slack, Visual Studio Code (VS Code)
The most amazing...
...thing I have developed is a new type of cryptocurrency that automatically trades between stablecoin and a basket of top assets to maintain and grow.
Work Experience
Chief Technology Officer
2018 - PRESENT
Lab27
- Managed a great team and built an industry leader in fuel management software called FuelRite which helps fuel wholesalers manage stock, track logistics, and facilitate customer and supplier orders.
- Used Azure DevOps for all projects and had CI/CD for most projects and managed all issues on DevOps, too.
- Launched a number of successful ICOs for clients. More recently I have architected and mostly written the code for NFT projects. Most notably, these images and metadata are stored on IPFS and we have included royalties by leveraging EIP-2981.
Technologies: Blockchain, Web3.js, Aurelia, TypeScript, C#.NET, React, Blazor, Node.js, Azure DevOps, MacOS, OpenZeppelin, Ethereum Smart Contract, Ethereum, Ganache, Truffle, Smart Contracts, Blockchain & Cryptocurrency, HTML, JavaScript
Solidity Developer
2022 - 2022
Shane Richardson
- Created the main NFT contract and a marketplace contract. The site functionality is similar to ArtBlocks but with significant improvements. The concept of a project and whitelisting through Merkle trees were incorporated into the NFT contract.
- Tracked improvements through GitHub issues, and I used Hardhat and Gas Reporter for testing and optimization.
- Fulfilled the requirement and wrote extensive tests over 50 to ensure contracts were solid.
Technologies: Solidity, Blockchain, JavaScript, Ethereum Smart Contract, Non-fungible Tokens (NFT), Ethereum, Web3.js, Hardhat, Node.js, Vue
Senior React and Web3 Developer for a Blockchain Company
2022 - 2022
Libertas GH PTY LTD
- Developed a decentralized NFT Marketplace for their TSF blockchain. The marketplace allowed users to mint, list, offer, and auction NFTs.
- Built the first marketplace for the TSF network, and we used IPFS for all metadata and image storage.
- Improved speed, given that the platform had full metamask integration, by syncing the smart contract storage and IPFS metadata to MongoDB.
Technologies: React, Web3.js, Node.js, Smart Contracts, Truffle
Senior Full-stack Developer
2015 - 2017
NRTH
- Developed a CRM-based system for the real estate industry that is still used and loved today.
- Used Jira for issue tracking and TeamCity for CI/CD.
- Built a very cool app for bookies in the horse racing game. The app assisted them in hedging large bets by back betting against a competitor to negate potential losses.
Technologies: Aurelia, ASP.NET, TypeScript, Web MVC, Jira, TeamCity, Node.js, AngularJS, HTML, JavaScript
Founder
2007 - 2014
Cherangani
- Started the company in 2007 to assist multilevel marketers who were building the Amway business to track their network. It was the only one like it in the world.
- Built a system that scraped team members and their upline/downline relationships and presented the information graphically online using SVG. Users could annotate their teams and collaborate on how to grow the team further.
- Integrated automated debit orders into the platform using Netcash.
Technologies: DotNetNuke (DNN), C#, SQL, SVG, HTML, JavaScript
Senior Full-stack Developer
2009 - 2010
3fifteen Technology Solutions Pty (Ltd)
- Helped start the Durban office as the first developer.
- Implemented a safety, health, and environment app on MS SharePoint for a very large and reputable paper producer.
- Worked on a business process application that facilitated the registration of new stock items and their corresponding barcodes to a global registrar. This was for one of the largest retailers in the country.
Technologies: SharePoint, C#.NET, HTML, JavaScript
Experience
FuelRite
A fuel management system for wholesale distributors in Africa. It manages both fleet and depot stock and the full logistics for deliveries. Google APIs are leveraged for optimal routing and driver apps poll location to notify customers of distance and time to delivery.
Minted History
A unique NFT project, unlike most of the PFP (profile pic) projects out there. Our collection displays newspaper headlines of notable moments in crypto history. We created a minting page that allowed for early bird mints and public mints. In addition, the smart contract implements royalties that allow for a 5% share of all secondary sales in perpetuity.
In order to further bolster value, I created a lottery platform where these NFTs can be staked in return for tokens and points towards a lottery. Based on token rarity, points are multiplied, and as a result, these points translate into tickets for a monthly lottery, where a portion of the mint revenue is staked and earning APY.
In order to further bolster value, I created a lottery platform where these NFTs can be staked in return for tokens and points towards a lottery. Based on token rarity, points are multiplied, and as a result, these points translate into tickets for a monthly lottery, where a portion of the mint revenue is staked and earning APY.
Learn to Break Free
A web portal for Independent Business Owners (IBO) building the Amway business. The platform scraped the line of sponsorship for the IBO and presented a graphical format of their group. In addition, we scraped information from their education partner and superimposed this over the SVG graphics to create a holistic real-time snapshot of their teams.
I implemented automated debit orders, using Docusign and Netcash.
I implemented automated debit orders, using Docusign and Netcash.
Demoverse
https://www.demoverse.comBuilt all of the web3 components for an NFT platform for the music industry. The smart contracts managed artist royalties and provided a marketplace to manage the listing and auction of the music NFTs.
Phigitals
I built all the web3 components for a clothing-based NFT platform, which included a marketplace contract that managed the listing of these NFTs. We had to develop a unique staking system that allowed us to track ownership of the NFT to the physical asset (item of clothing) in an escrow system.
Certifications
JUNE 1999 - PRESENT
CompTIA N+
The Computing Technology Industry Association (CompTIA)
MARCH 1999 - PRESENT
CompTIA A+
The Computing Technology Industry Association (CompTIA)
MARCH 1999 - PRESENT
Microsoft Certified Solution Developer
Microsoft
Skills
Libraries/APIs
Web3.js, OpenZeppelin, React, Node.js, Google Maps API, Vue
Tools
Ganache, Slack, Jira, TeamCity
Languages
C#, Solidity, TypeScript, HTML, JavaScript, SQL, C#.NET, HTML5
Frameworks
.NET, Truffle, AngularJS, Tendermint, Cosmos SDK, Next.js, Aurelia, Blazor, ASP.NET, Hardhat
Paradigms
Azure DevOps
Platforms
Ethereum, Blockchain, Windows, MacOS, Azure PaaS, SharePoint, Visual Studio Code (VS Code), DotNetNuke (DNN)
Other
Ethereum Smart Contract, Smart Contracts, Blockchain & Cryptocurrency, Non-fungible Tokens (NFT), Ethermint, WhatsApp, WebAssembly (Wasm), Avalanche C-Chain, Web MVC, SVG, Computer Skills, Networking, DocuSign
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