MINE: NFT Marketplace for title deeds of physical properties (cars, motorcycles, boats, among others).
MINE is a platform that allows transactions without the need of buyers and sellers physical presence in the places or countries where the operation is carried out. With purchase / sales transactions paid in cryptocurrencies, protected purchases for the security protection of both the buyer and the seller.
This solution is based on Web3 technologies, through the creation of a DApp deployed on the Ethereum Blockchain.
Users (buyers, sellers) must connect their Wallet to:
Register new goods for sale.
Additionally, they must have contact information to negotiate goods and prices:
ID / Driver’s License.
There will be a public display of the goods. Observers also need a Wallet to query and view.
Goods will be displayed by categories.
The currency to display the prices of the Goods will be US Dollar and the official exchange currency will be the ETH (the Ethereum cryptocurrency).
Initially it will only be available in Medellín, Colombia.
A commission will be associated with each of the NFTs registered in the DApp so that each time this NFT is transferred it sends a percentage to the owner of the Smart Contract.
A commission will be charged for each sale made.
What problem does the project solve?
Has it happened to you that you want to buy or sell a vehicle outside your location, and you don’t find the people or tools necessary to perform the transaction?
Are you tired of Marketplaces on social networks that do not deliver the true information of what you are looking for, and if you offer a product, it is not given enough visibility?
Are you tired of paying high commissions for bank transfers to pay for goods?
How the NFT Marketplacesolve it?
MINE: A NFT Marketplace that allows transactions without the need for physical presence of buyers and sellers in the localities or countries where the operation is carried out, with purchase / sale transactions paid in cryptocurrencies, with protected purchases for the protection of the security of both the buyer and the seller.
This solution is based on web3 technologies, through the creation of a DApp deployed on the Ethereum Blockchain.
Impact on Society
In Latin America there is no NFT Marketplace for physical goods like this.
Time saving. Buyer and seller can make transactions without leaving home/office.
Trust and credibility between the parties: because the Goods are audited by certified experts, and these Experts can be chosen by the buyers.
Do not go through banks: thus, avoiding intermediaries.
Avoid high fees for large transactions and/or international transfers.
Value Added to Web2
Business logic is a Smart Contract.
The App Frontend cannot be censored.
The data is not under the control of the developers.
The Blockchain where the Smart Contract is deployed is Ethereum.
The Frontend is built an open source.
Traceability of goods, transactions, signatures of involved.
NFT Marketplace user types
Puts the money from the purchase of the Good.
You must have the funds in your Wallet.
Pay the tax.
Owner of Good.
It must cover the expenses of the publication of the contract and the NFT mint (issuance), with the characteristics specified below.
Pay the Expert’s fee or certification.
Experts / Certifiers:
Certify the validity of the Good, then it can be sold.
Sign the transaction when the Owner Property is changed on a physical world.
Charge transaction fees.
Digital Document Creation Service: If a product does not have a title deed, it is generated.
The expert is legally responsible for the transaction.
He/she performs the legal property transfer in the real world.
At the digital level, sign the transaction with his/her address / Wallet.
Administrator (our Wallet):
Send to execute transferFrom from the buyer’s account to the seller’s.
Apart from the main photo, there may be additional photos (example: the motorcycle, vehicle, or boat from different angles).
A section of photos only visible to the seller and the buyer who already gives their approval of purchase intention, and the experts. One or more of them will be the ownership legal document.
Conversion from ETH to USD/COP or other currency, and vice versa.
Duplicate NFT (that the same Good for sale is published several times).
More than one owner.
Penalties in case of fraud in the properties.
NFT Marketplace Architecture
The goods may only be sold when they are verified by a certified Expert. Experts must have an official certification to exercise their functions, validated by the regulatory entities in the region where they carry out their activities. For this, a badge will appear when displaying the Good indicating such condition.
The Experts will be responsible for auditing and certifying that the Goods exist and are in order. On them will fall the legal responsibility of legitimacy of the Goods. They will be able to interact with the system using their Wallets and earning a commission for purchases and sales.
Purchase / sale of real estate: real estate, commercial premises, among others adding to the Metadata address, GPS coordinates, photos of exteriors and interiors.
Purchase/sale of virtual assets: plots in the Metaverse, NFT works of art, among others.
Purchase / sale of Jewelry.
Auction of goods and assets.
Expand the operation to other Latin American countries and regions.
Use as a means of payment Stable Coins as Tether (USDT).
Additional photos in the Metadata of the Goods, as well as private photos.
Encryption of sensitive user data (PII) stored in the IPFS.
Display prices in local currency (e.g., COP).
Web3.js (Wallet connection)
VS Code (coding & peer programming)
Chain.link (exchange rate integration between ETH – and USDT)
Our call as a team was quite spontaneous. Eimer summoned Carlos, then both summoned on channel #General of the Discord of the #EthDevProgram challenge and then Javier, José and Fidelina appeared. Eventually, the group adopted the name GOF5 (Gang of Five).
There was a spirit of equality among us, and everyone’s interventions were respected. This came naturally from the beginning.
We started meeting to see what ideas we had. Each one presented his idea, and with a mastermind we were adding details and other things that were appearing.
We let the idea land for a day or two, and then it was put to a vote. No one lobbied, no advertising, no lobbying. No votes were bought. It didn’t matter whose ideas they were either.
We agreed to start doing daily meetings to achieve the goals. The first meetings last less than 1 hour to put the mastermind to work and shape the project.
After establishing the Jira board, starting to create and assign tasks in the Backlog, we meet daily in Stand Ups of 15-20 minutes to follow up, seeing what was done the day before, what is planned to be done today and the existence of some blockage.
We started working on the Whitepaper, in somewhat marathonic meetings (3-5 hours) but very productive. We delimit the project, describe actors, procedures, and above all, the conceptual part: the history, the impact, added value of Web 3 on doing it in Web 2, possible problems, legal framework, pitch, technologies, among other things.
At one point we lost faith in the project, because we came to think that the conceptual part regarding the advantages of the Blockchain vs the current applications of Web 2.0 and the complexity of the legal issues involved in the transfer of goods did not make much sense, however, we managed to establish well the added value that we can give by solving the problem with our platform that would facilitate and give security in the user’s purchase / sale of goods.
In another marathonic session we defined the 90-second Pitch Elevator, the presentation of the project, the logos for the DApp and the group, and a model with the design of the screens.
With the agenda for the next 2 weeks clearer, we started working in teams for the Frontend, Backend and Operations.
Our official slogan: “Let’s solve with what we have“.
Work Methodology, Monitoring and Deliverables
We established Scrum as an agile work methodology and Jira as a tool to follow up.
We established 1-week Sprint starting August 23, 2022.
It was done in 2 Sprints and at the end of each one there was a deliverable:
It is convened each year to educate and empower the community to build and use decentralized systems.
It’s a conference for builders of all kinds: developers, designers, researchers, customer implementers, test engineers, infrastructure operators, community organizers, social economists, artists, and more.
For me it was pure magic. Words are not enough to describe this incredible experience.
Thanks to the full support received by Source Meridian, this experience was possible for me.
Besides all the new people I met from the community and the ecosystem, besides from meeting many of the peers, mentors and professors of the Ethereum Developer Program, it was realizing the way forward to consolidate myself as a Blockchain Developer.
Preamble to Devcon
I finished the Ethereum Developer Program on September 13th, 2022. It was just 3 intense months where I felt like a university student again, with the rush of the homework deliveries, courses & practices to accomplish on time, and the final project we had to build in 2 weeks.
The Ethereum Developer Program changed something inside me, an emotion I had dormant since 2018 when I did Ethereum mining with my own RIG.
Our folks at Platzi got us special price Developer tickets for Devcon from the Ethereum Foundation and I thought “I want to be there; I want to be a part of it”. I asked for support from Source Meridian, the company where I have the privilege of working since 2019, and they supported me in everything; As usual, it was a high class support: unbeatable accommodation, plane tickets, travel expenses, taxis, everything.
Another talk that I really liked was the interview with Vitalik Buterin. The interviewer asked him, “What can you tell us to confirm that Vitalik is a human and not a reptilian?” After looking a little embarrassed, Vitalik replied, “I’m not a computer, I’m not a superhuman, I’m a normal person. You all cando a lot in our ecosystem, anything is possible in our community.“
Some of my colleagues from the Ethereum Developer Program of Platzi participated as Developers and collaborators and I was able to know first-hand their experiences, which encouraged me to participate in the next events of this type.
I could see the quantity and quality of the projects, highlighting those of Push.org (to send notifications between users via Wallets) and Lit Protocol (file encryption in IPFS, among other interesting features).
Subtraction is about avoiding to give much power to institutions or groups of people, as happens in the world of companies and governments. “Subtracting does not mean doing less, it means subtracting your power in order to achieve more education, communication, coordination and research.”
Another talk at the opening was that of Vitalik Buterin “Ethereum in 30 Minutes“. He explained conceptual and technical aspects of the Blockchain, the new PoS (Proof of Stake) consensus mechanism, the flow of transactions, the structure of blocks, Merkle Trees, high-level languages, and the next steps after The Merge.
The archive of Talks and Workshops can be accessed through the address:
I remember one in particular, the “DAO Governance Design Jam” about the dynamics of decision-making in a DAO, in which we had the opportunity to share with @LayerOne, contributor at MakerDAO SES, who shared real-life experiences in a decentralized autonomous organization.
I had the opportunity to attend workshops on the new way to reach consensus through PoS (Proof of Stake), where I could understand among other things the concept of MEV (Maximal Extractable Value), which refers to the maximum value that can be extracted from the production of blocks above the reward of these, and standard gas tariffs including, excluding and changing the order of transactions in a block. It is a way for PoS validators or participants to prioritize the blocks they are going to process, maximizing their profits.
In the workshop “Demystifying Ethereum Assembly” we learned how to embed Assembly in Solidity (the programming language to create Smart Contracts on the Ethereum EVM). Although it is a little more difficult to understand and implement, this way of programming saves GAS fees, which are a topic of great debate in the Ethereum community due to the high operating costs; a high point in the adoption of this Blockchain.
In the workshop “Hunting and Monitoring for On-Chain Attacks“, we learned how to dissect a real-world chain attack, classifying each step the attacker can take into four distinct stages (financing, preparation, exploitation and money laundering) and went through the development of a heuristic/ML approach to identify these attacks using the Forta network.
In the workshop “Build a DApp on Optimism: How to Conquer L2 Bridging“, we learned how to easily create a DApp that leverages Truffle’s L2 Bridge Box, which helps you quickly set up a DApp to handle all the complexities that come with the L2 bridge. These bridges allow to offload to the Mainnet (L1) of expensive operations, performing the calculations and updating the status of the L1 only with the results, and leaving the computation and detail of the results in the L2.
Danksharding is basically a proposal to be able to increase the amount of data that can be stored on the Blockchain, so that it can be used as the databases of our times. This is because the cost of storage in Ethereum is expensive, which limits its use and size.
There were a lot of side events to the Devcon Bogota 2022.
I had the opportunity to go to several, including the Chain.Link Workshop on NFT Dinamicos at the Platzi offices, the Platzi and NEAR event at the Hilton Hotel, the Open Zeppelin meeting at the Hyatt Grand Bogotá
And the great Rave parties of ETH Global, Reserve and Zulu at the best Bogotá’s party sites.
As Platzi students we had the opportunity to meet the mentors, teachers and representatives of the Latin America’s largest e-learning platform who led the Ethereum Developer Program, as well as all the Ethereum Foundation folks.
SWAG: the gifts
Devcon and the place of SWAGs. These are gifts given by service providers, sponsors, or people who promote their projects. The gifts are mostly flannels, caps, sweaters, coffee cups, among others. I had to buy a bigger suitcase so I could bring everything they gave me.
One of my favorites was the ENS SWAG for having my domain name “carlosjramirez.eth”. The gift consisted of an ID card with my avatar and the experience of an NFC device that generates a POAP (Proof of Attendance Protocol) when bringing the smartphone closer to the ID card. The POAP carries the message “I met carlosjramirez.eth at Devcon 6“.
POAPs are used as proof that you were in a place, attended an event, or met someone.
Another interesting SWAG was the “ETHER Coffee: Devcon Bogotá Special Blend” they gave us as Devcon’s registration souvenir. A great detail without a doubt.
The Closing Ceremony
“Ethereum is not just a technology, Ethereum is a community, it is a movement, and just like all movements, all communities, we have values. And one of those values is civil liberties, civil rights.“
Kurt Opssahl spoke about “Privacy and Free Expression” and the importance of expanding the Ethereum developer community, of staying united, of continuing to develop applications and protocols to strengthen the decentralized paradigm, the union and to be able to counteract the censorship actions of the system against the movement.
He highlighted the Tornado Cash case. One of the programmers, Alexey Pertsev, was arrested in the Netherlands and is in jail without formal charges or trial date. Accused by OFAC (Office of Foreign Assets Control) in August 2022 of money laundering for the nature of the Dapp he developed alongside Roman Semenov and Roman Storm, and his role in laundering more than $455 million in cryptocurrencies stolen by the North Korea-linked Lazarus Group hacking organization.
According to Chainalysis’ blog: “Tornado Cash can be a practical solution for legitimate users seeking financial privacy, such as those who wish to donate to political causes without making details public or those who wish to keep information about their wealth private. But it’s also attractive to cybercriminals looking to launder money. The Treasury press release announcing the Tornado Cash sanctions specifically noted Tornado Cash’s role in laundering more than $455 million in cryptocurrency stolen from Axie Infinity’s Ronin Bridge protocol by North Korea-affiliated hacking organization Lazarus Group, and its receipt of funds stolen from Harmony Bridge and Nomad Bridge in June and August of this year. Since 2019, almost 30% of the funds sent through it have been linked to illicit actors, and the Democratic People’s Republic of Korea has been one of its main beneficiaries.”
The biggest surprise was the end, when Skylar said “well, with this we concluded the Devcon, so thank you for everything and now, let’s go back to building“. Everything seemed like an emotionless ending, when suddenly someone said “hello, eh, I have a question … are we Melos?” (it means “Are we good?“) and began the spectacular closing with a Colombian Barranquilla’s Carnival style party.
The Devcon’s closing party
The closing party of the Devcon Bogotá 2022 lasted hours, people did not stop dancing in a phenomenal music mash-up.
It was amazing the high energy in the event.
Networking was awesome. At lunches we had the opportunity to meet many developers and owners of projects and protocols, as well as investors.
After the presentations, talks and workshops, the most important part of Devcon is networking, meeting people, making contacts, sharing experiences, and making community.
Solidity is a high-level contract-oriented language.
Solidity is statically typed and accepts, among other things, inheritances, libraries, and complex user-defined types.
What is Chainlink’s Automation
Chainlink’s Automation (previously named “Chainlink Keepers”) is a decentralized off-chain computing layer to automate smart contract functions and introduce new features to dApp.
Developers no longer must carry out processes manually, rely on centralized servers, or make changes to their protocol in order to automate on-chain functions when certain conditions are met. Instead, they can delegate that task to Chainlink Keepers.