More on Web3 & Crypto

mbvissers.eth
3 years ago
Why does every smart contract seem to implement ERC165?
ERC165 (or EIP-165) is a standard utilized by various open-source smart contracts like Open Zeppelin or Aavegotchi.
What's it? You must implement? Why do we need it? I'll describe the standard and answer any queries.
What is ERC165
ERC165 detects and publishes smart contract interfaces. Meaning? It standardizes how interfaces are recognized, how to detect if they implement ERC165, and how a contract publishes the interfaces it implements. How does it work?
Why use ERC165? Sometimes it's useful to know which interfaces a contract implements, and which version.
Identifying interfaces
An interface function's selector. This verifies an ABI function. XORing all function selectors defines an interface in this standard. The following code demonstrates.
// SPDX-License-Identifier: UNLICENCED
pragma solidity >=0.8.0 <0.9.0;
interface Solidity101 {
function hello() external pure;
function world(int) external pure;
}
contract Selector {
function calculateSelector() public pure returns (bytes4) {
Solidity101 i;
return i.hello.selector ^ i.world.selector;
// Returns 0xc6be8b58
}
function getHelloSelector() public pure returns (bytes4) {
Solidity101 i;
return i.hello.selector;
// Returns 0x19ff1d21
}
function getWorldSelector() public pure returns (bytes4) {
Solidity101 i;
return i.world.selector;
// Returns 0xdf419679
}
}This code isn't necessary to understand function selectors and how an interface's selector can be determined from the functions it implements.
Run that sample in Remix to see how interface function modifications affect contract function output.
Contracts publish their implemented interfaces.
We can identify interfaces. Now we must disclose the interfaces we're implementing. First, import IERC165 like so.
pragma solidity ^0.4.20;
interface ERC165 {
/// @notice Query if a contract implements an interface
/// @param interfaceID The interface identifier, as specified in ERC-165
/// @dev Interface identification is specified in ERC-165.
/// @return `true` if the contract implements `interfaceID` and
/// `interfaceID` is not 0xffffffff, `false` otherwise
function supportsInterface(bytes4 interfaceID) external view returns (bool);
}We still need to build this interface in our smart contract. ERC721 from OpenZeppelin is a good example.
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/ERC721.sol)
pragma solidity ^0.8.0;
import "./IERC721.sol";
import "./extensions/IERC721Metadata.sol";
import "../../utils/introspection/ERC165.sol";
// ...
contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
// ...
function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
return
interfaceId == type(IERC721).interfaceId ||
interfaceId == type(IERC721Metadata).interfaceId ||
super.supportsInterface(interfaceId);
}
// ...
}I deleted unnecessary code. The smart contract imports ERC165, IERC721 and IERC721Metadata. The is keyword at smart contract declaration implements all three.
Kind (interface).
Note that type(interface).interfaceId returns the same as the interface selector.
We override supportsInterface in the smart contract to return a boolean that checks if interfaceId is the same as one of the implemented contracts.
Super.supportsInterface() calls ERC165 code. Checks if interfaceId is IERC165.
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IERC165).interfaceId;
}So, if we run supportsInterface with an interfaceId, our contract function returns true if it's implemented and false otherwise. True for IERC721, IERC721Metadata, andIERC165.
Conclusion
I hope this post has helped you understand and use ERC165 and why it's employed.
Have a great day, thanks for reading!

Trent Lapinski
3 years ago
What The Hell Is A Crypto Punk?
We are Crypto Punks, and we are changing your world.
A “Crypto Punk” is a new generation of entrepreneurs who value individual liberty and collective value creation and co-creation through decentralization. While many Crypto Punks were born and raised in a digital world, some of the early pioneers in the crypto space are from the Oregon Trail generation. They were born to an analog world, but grew up simultaneously alongside the birth of home computing, the Internet, and mobile computing.
A Crypto Punk’s world view is not the same as previous generations. By the time most Crypto Punks were born everything from fiat currency, the stock market, pharmaceuticals, the Internet, to advanced operating systems and microprocessing were already present or emerging. Crypto Punks were born into pre-existing conditions and systems of control, not governed by logic or reason but by greed, corporatism, subversion, bureaucracy, censorship, and inefficiency.
All Systems Are Human Made
Crypto Punks understand that all systems were created by people and that previous generations did not have access to information technologies that we have today. This is why Crypto Punks have different values than their parents, and value liberty, decentralization, equality, social justice, and freedom over wealth, money, and power. They understand that the only path forward is to work together to build new and better systems that make the old world order obsolete.
Unlike the original cypher punks and cyber punks, Crypto Punks are a new iteration or evolution of these previous cultures influenced by cryptography, blockchain technology, crypto economics, libertarianism, holographics, democratic socialism, and artificial intelligence. They are tasked with not only undoing the mistakes of previous generations, but also innovating and creating new ways of solving complex problems with advanced technology and solutions.
Where Crypto Punks truly differ is in their understanding that computer systems can exist for more than just engagement and entertainment, but actually improve the human condition by automating bureaucracy and inefficiency by creating more efficient economic incentives and systems.
Crypto Punks Value Transparency and Do Not Trust Flawed, Unequal, and Corrupt Systems
Crypto Punks have a strong distrust for inherently flawed and corrupt systems. This why Crypto Punks value transparency, free speech, privacy, and decentralization. As well as arguably computer systems over human powered systems.
Crypto Punks are the children of the Great Recession, and will never forget the economic corruption that still enslaves younger generations.
Crypto Punks were born to think different, and raised by computers to view reality through an LED looking glass. They will not surrender to the flawed systems of economic wage slavery, inequality, censorship, and subjection. They will literally engineer their own unstoppable financial systems and trade in cryptography over fiat currency merely to prove that belief systems are more powerful than corruption.
Crypto Punks are here to help achieve freedom from world governments, corporations and bankers who monetizine our data to control our lives.
Crypto Punks Decentralize
Despite all the evils of the world today, Crypto Punks know they have the power to create change. This is why Crypto Punks are optimistic about the future despite all the indicators that humanity is destined for failure.
Crypto Punks believe in systems that prioritize people and the planet above profit. Even so, Crypto Punks still believe in capitalistic systems, but only capitalistic systems that incentivize good behaviors that do not violate the common good for the sake of profit.
Cyber Punks Are Co-Creators
We are Crypto Punks, and we will build a better world for all of us. For the true price of creation is not in US dollars, but through working together as equals to replace the unequal and corrupt greedy systems of previous generations.
Where they have failed, Crypto Punks will succeed. Not because we want to, but because we have to. The world we were born into is so corrupt and its systems so flawed and unequal we were never given a choice.
We have to be the change we seek.
We are Crypto Punks.
Either help us, or get out of our way.
Are you a Crypto Punk?

Julie Plavnik
3 years ago
How to Become a Crypto Broker [Complying and Making Money]
Three options exist. The third one is the quickest and most fruitful.
You've mastered crypto trading and want to become a broker.
So you may wonder: Where to begin?
If so, keep reading.
Today I'll compare three different approaches to becoming a cryptocurrency trader.
What are cryptocurrency brokers, and how do they vary from stockbrokers?
A stockbroker implements clients' market orders (retail or institutional ones).
Brokerage firms are regulated, insured, and subject to regulatory monitoring.
Stockbrokers are required between buyers and sellers. They can't trade without a broker. To trade, a trader must open a broker account and deposit money. When a trader shops, he tells his broker what orders to place.
Crypto brokerage is trade intermediation with cryptocurrency.
In crypto trading, however, brokers are optional.
Crypto exchanges offer direct transactions. Open an exchange account (no broker needed) and make a deposit.
Question:
Since crypto allows DIY trading, why use a broker?
Let's compare cryptocurrency exchanges vs. brokers.
Broker versus cryptocurrency exchange
Most existing crypto exchanges are basically brokers.
Examine their primary services:
connecting purchasers and suppliers
having custody of clients' money (with the exception of decentralized cryptocurrency exchanges),
clearance of transactions.
Brokerage is comparable, don't you think?
There are exceptions. I mean a few large crypto exchanges that follow the stock exchange paradigm. They outsource brokerage, custody, and clearing operations. Classic exchange setups are rare in today's bitcoin industry.
Back to our favorite “standard” crypto exchanges. All-in-one exchanges and brokers. And usually, they operate under a broker or a broker-dealer license, save for the exchanges registered somewhere in a free-trade offshore paradise. Those don’t bother with any licensing.
What’s the sense of having two brokers at a time?
Better liquidity and trading convenience.
The crypto business is compartmentalized.
We have CEXs, DEXs, hybrid exchanges, and semi-exchanges (those that aggregate liquidity but do not execute orders on their sides). All have unique regulations and act as sovereign states.
There are about 18k coins and hundreds of blockchain protocols, most of which are heterogeneous (i.e., different in design and not interoperable).
A trader must register many accounts on different exchanges, deposit funds, and manage them all concurrently to access global crypto liquidity.
It’s extremely inconvenient.
Crypto liquidity fragmentation is the largest obstacle and bottleneck blocking crypto from mass adoption.
Crypto brokers help clients solve this challenge by providing one-gate access to deep and diverse crypto liquidity from numerous exchanges and suppliers. Professionals and institutions need it.
Another killer feature of a brokerage may be allowing clients to trade crypto with fiat funds exclusively, without fiat/crypto conversion. It is essential for professional and institutional traders.
Who may work as a cryptocurrency broker?
Apparently, not anyone. Brokerage requires high-powered specialists because it involves other people's money.
Here's the essentials:
excellent knowledge, skills, and years of trading experience
high-quality, quick, and secure infrastructure
highly developed team
outstanding trading capital
High-ROI network: long-standing, trustworthy connections with customers, exchanges, liquidity providers, payment gates, and similar entities
outstanding marketing and commercial development skills.
What about a license for a cryptocurrency broker? Is it necessary?
Complex question.
If you plan to play in white-glove jurisdictions, you may need a license. For example, in the US, as a “money transmitter” or as a CASSP (crypto asset secondary services provider) in Australia.
Even in these jurisdictions, there are no clear, holistic crypto brokerage and licensing policies.
Your lawyer will help you decide if your crypto brokerage needs a license.
Getting a license isn't quick. Two years of patience are needed.
How can you turn into a cryptocurrency broker?
Finally, we got there! 🎉
Three actionable ways exist:
To kickstart a regulated stand-alone crypto broker
To get a crypto broker franchise, and
To become a liquidity network broker.
Let's examine each.
1. Opening a regulated cryptocurrency broker
It's difficult. Especially If you're targeting first-world users.
You must comply with many regulatory, technical, financial, HR, and reporting obligations to keep your organization running. Some are mentioned above.
The licensing process depends on the products you want to offer (spots or derivatives) and the geographic areas you plan to service. There are no general rules for that.
In an overgeneralized way, here are the boxes you will have to check:
capital availability (usually a large amount of capital c is required)
You will have to move some of your team members to the nation providing the license in order to establish an office presence there.
the core team with the necessary professional training (especially applies to CEO, Head of Trading, Assistant to Head of Trading, etc.)
insurance
infrastructure that is trustworthy and secure
adopted proper AML/KYC/financial monitoring policies, etc.
Assuming you passed, what's next?
I bet it won’t be mind-blowing for you that the license is just a part of the deal. It won't attract clients or revenue.
To bring in high-dollar clientele, you must be a killer marketer and seller. It's not easy to convince people to give you money.
You'll need to be a great business developer to form successful, long-term agreements with exchanges (ideally for no fees), liquidity providers, banks, payment gates, etc. Persuade clients.
It's a tough job, isn't it?
I expect a Quora-type question here:
Can I start an unlicensed crypto broker?
Well, there is always a workaround with crypto!
You can register your broker in a free-trade zone like Seychelles to avoid US and other markets with strong watchdogs.
This is neither wise nor sustainable.
First, such experiments are illegal.
Second, you'll have trouble attracting clients and strategic partners.
A license equals trust. That’s it.
Even a pseudo-license from Mauritius matters.
Here are this method's benefits and downsides.
Cons first.
As you navigate this difficult and expensive legal process, you run the risk of missing out on business prospects. It's quite simple to become excellent compliance yet unable to work. Because your competitors are already courting potential customers while you are focusing all of your effort on paperwork.
Only God knows how long it will take you to pass the break-even point when everything with the license has been completed.
It is a money-burning business, especially in the beginning when the majority of your expenses will go toward marketing, sales, and maintaining license requirements. Make sure you have the fortitude and resources necessary to face such a difficult challenge.
Pros
It may eventually develop into a tool for making money. Because big guys who are professionals at trading require a white-glove regulated brokerage. You have every possibility if you work hard in the areas of sales, marketing, business development, and wealth. Simply put, everything must align.
Launching a regulated crypto broker is analogous to launching a crypto exchange. It's ROUGH. Sure you can take it?
2. Franchise for Crypto Broker (Crypto Sub-Brokerage)
A broker franchise is easier and faster than becoming a regulated crypto broker. Not a traditional brokerage.
A broker franchisee, often termed a sub-broker, joins with a broker (a franchisor) to bring them new clients. Sub-brokers market a broker's products and services to clients.
Sub-brokers are the middlemen between a broker and an investor.
Why is sub-brokering easier?
less demanding qualifications and legal complexity. All you need to do is keep a few certificates on hand (each time depends on the jurisdiction).
No significant investment is required
there is no demand that you be a trading member of an exchange, etc.
As a sub-broker, you can do identical duties without as many rights and certifications.
What about the crypto broker franchise?
Sub-brokers aren't common in crypto.
In most existing examples (PayBito, PCEX, etc.), franchises are offered by crypto exchanges, not brokers. Though we remember that crypto exchanges are, in fact, brokers, do we?
Similarly:
For a commission, a franchiser crypto broker receives new leads from a crypto sub-broker.
See above for why enrolling is easy.
Finding clients is difficult. Most crypto traders prefer to buy-sell on their own or through brokers over sub-broker franchises.
3. Broker of the Crypto Trading Network (or a Network Broker)
It's the greatest approach to execute crypto brokerage, based on effort/return.
Network broker isn't an established word. I wrote it for clarity.
Remember how we called crypto liquidity fragmentation the current crypto finance paradigm's main bottleneck?
Where there's a challenge, there's progress.
Several well-funded projects are aiming to fix crypto liquidity fragmentation. Instead of launching another crypto exchange with siloed trading, the greatest minds create trading networks that aggregate crypto liquidity from desynchronized sources and enable quick, safe, and affordable cross-blockchain transactions. Each project offers a distinct option for users.
Crypto liquidity implies:
One-account access to cryptocurrency liquidity pooled from network participants' exchanges and other liquidity sources
compiled price feeds
Cross-chain transactions that are quick and inexpensive, even for HFTs
link between participants of all kinds, and
interoperability among diverse blockchains
Fast, diversified, and cheap global crypto trading from one account.
How does a trading network help cryptocurrency brokers?
I’ll explain it, taking Yellow Network as an example.
Yellow provides decentralized Layer-3 peer-to-peer trading.
trade across chains globally with real-time settlement and
Between cryptocurrency exchanges, brokers, trading companies, and other sorts of network members, there is communication and the exchange of financial information.
Have you ever heard about ECN (electronic communication network)? If not, it's an automated system that automatically matches buy and sell orders. Yellow is a decentralized digital asset ECN.
Brokers can:
Start trading right now without having to meet stringent requirements; all you need to do is integrate with Yellow Protocol and successfully complete some KYC verification.
Access global aggregated crypto liquidity through a single point.
B2B (Broker to Broker) liquidity channels that provide peer liquidity from other brokers. Orders from the other broker will appear in the order book of a broker who is peering with another broker on the market. It will enable a broker to broaden his offer and raise the total amount of liquidity that is available to his clients.
Select a custodian or use non-custodial practices.
Comparing network crypto brokerage to other types:
A licensed stand-alone brokerage business is much more difficult and time-consuming to launch than network brokerage, and
Network brokerage, in contrast to crypto sub-brokerage, is scalable, independent, and offers limitless possibilities for revenue generation.
Yellow Network Whitepaper. has more details on how to start a brokerage business and what rewards you'll obtain.
Final thoughts
There are three ways to become a cryptocurrency broker, including the non-conventional liquidity network brokerage. The last option appears time/cost-effective.
Crypto brokerage isn't crowded yet. Act quickly to find your right place in this market.
Choose the way that works for you best and see you in crypto trading.
Discover Web3 & DeFi with Yellow Network!
Yellow, powered by Openware, is developing a cross-chain P2P liquidity aggregator to unite the crypto sector and provide global remittance services that aid people.
Join the Yellow Community and plunge into this decade's biggest product-oriented crypto project.
Observe Yellow Twitter
Enroll in Yellow Telegram
Visit Yellow Discord.
On Hacker Noon, look us up.
Yellow Network will expose development, technology, developer tools, crypto brokerage nodes software, and community liquidity mining.
You might also like

SAHIL SAPRU
3 years ago
How I grew my business to a $5 million annual recurring revenue
Scaling your startup requires answering customer demands, not growth tricks.
I cofounded Freedo Rentals in 2019. I reached 50 lakh+ ARR in 6 months before quitting owing to the epidemic.
Freedo aimed to solve 2 customer pain points:
Users lacked a reliable last-mile transportation option.
The amount that Auto walas charge for unmetered services
Solution?
Effectively simple.
Build ports at high-demand spots (colleges, residential societies, metros). Electric ride-sharing can meet demand.
We had many problems scaling. I'll explain using the AARRR model.
Brand unfamiliarity or a novel product offering were the problems with awareness. Nobody knew what Freedo was or what it did.
Problem with awareness: Content and advertisements did a poor job of communicating the task at hand. The advertisements clashed with the white-collar part because they were too cheesy.
Retention Issue: We encountered issues, indicating that the product was insufficient. Problems with keyless entry, creating bills, stealing helmets, etc.
Retention/Revenue Issue: Costly compared to established rivals. Shared cars were 1/3 of our cost.
Referral Issue: Missing the opportunity to seize the AHA moment. After the ride, nobody remembered us.
Once you know where you're struggling with AARRR, iterative solutions are usually best.
Once you have nailed the AARRR model, most startups use paid channels to scale. This dependence, on paid channels, increases with scale unless you crack your organic/inbound game.
Over-index growth loops. Growth loops increase inflow and customers as you scale.
When considering growth, ask yourself:
Who is the solution's ICP (Ideal Customer Profile)? (To whom are you selling)
What are the most important messages I should convey to customers? (This is an A/B test.)
Which marketing channels ought I prioritize? (Conduct analysis based on the startup's maturity/stage.)
Choose the important metrics to monitor for your AARRR funnel (not all metrics are equal)
Identify the Flywheel effect's growth loops (inertia matters)
My biggest mistakes:
not paying attention to consumer comments or satisfaction. It is the main cause of problems with referrals, retention, and acquisition for startups. Beyond your NPS, you should consider second-order consequences.
The tasks at hand should be quite clear.
Here's my scaling equation:
Growth = A x B x C
A = Funnel top (Traffic)
B = Product Valuation (Solving a real pain point)
C = Aha! (Emotional response)
Freedo's A, B, and C created a unique offering.
Freedo’s ABC:
A — Working or Studying population in NCR
B — Electric Vehicles provide last-mile mobility as a clean and affordable solution
C — One click booking with a no-noise scooter
Final outcome:
FWe scaled Freedo to Rs. 50 lakh MRR and were growing 60% month on month till the pandemic ceased our growth story.
How we did it?
We tried ambassadors and coupons. WhatsApp was our most successful A/B test.
We grew widespread adoption through college and society WhatsApp groups. We requested users for referrals in community groups.
What worked for us won't work for others. This scale underwent many revisions.
Every firm is different, thus you must know your customers. Needs to determine which channel to prioritize and when.
Users desired a safe, time-bound means to get there.
This (not mine) growth framework helped me a lot. You should follow suit.

Nicolas Tresegnie
3 years ago
Launching 10 SaaS applications in 100 days
Apocodes helps entrepreneurs create SaaS products without writing code. This post introduces micro-SaaS and outlines its basic strategy.
Strategy
Vision and strategy differ when starting a startup.
The company's long-term future state is outlined in the vision. It establishes the overarching objectives the organization aims to achieve while also justifying its existence. The company's future is outlined in the vision.
The strategy consists of a collection of short- to mid-term objectives, the accomplishment of which will move the business closer to its vision. The company gets there through its strategy.
The vision should be stable, but the strategy must be adjusted based on customer input, market conditions, or previous experiments.
Begin modestly and aim high.
Be truthful. It's impossible to automate SaaS product creation from scratch. It's like climbing Everest without running a 5K. Physical rules don't prohibit it, but it would be suicide.
Apocodes 5K equivalent? Two options:
(A) Create a feature that includes every setting option conceivable. then query potential clients “Would you choose us to build your SaaS solution if we offered 99 additional features of the same caliber?” After that, decide which major feature to implement next.
(B) Build a few straightforward features with just one or two configuration options. Then query potential clients “Will this suffice to make your product?” What's missing if not? Finally, tweak the final result a bit before starting over.
(A) is an all-or-nothing approach. It's like training your left arm to climb Mount Everest. My right foot is next.
(B) is a better method because it's iterative and provides value to customers throughout.
Focus on a small market sector, meet its needs, and expand gradually. Micro-SaaS is Apocode's first market.
What is micro-SaaS.
Micro-SaaS enterprises have these characteristics:
A limited range: They address a specific problem with a small number of features.
A small group of one to five individuals.
Low external funding: The majority of micro-SaaS companies have Total Addressable Markets (TAM) under $100 million. Investors find them unattractive as a result. As a result, the majority of micro-SaaS companies are self-funded or bootstrapped.
Low competition: Because they solve problems that larger firms would rather not spend time on, micro-SaaS enterprises have little rivalry.
Low upkeep: Because of their simplicity, they require little care.
Huge profitability: Because providing more clients incurs such a small incremental cost, high profit margins are possible.
Micro-SaaS enterprises created with no-code are Apocode's ideal first market niche.
We'll create our own micro-SaaS solutions to better understand their needs. Although not required, we believe this will improve community discussions.
The challenge
In 100 days (September 12–December 20, 2022), we plan to build 10 micro-SaaS enterprises using Apocode.
They will be:
Self-serve: Customers will be able to use the entire product experience without our manual assistance.
Real: They'll deal with actual issues. They won't be isolated proofs of concept because we'll keep up with them after the challenge.
Both free and paid options: including a free plan and a free trial period. Although financial success would be a good result, the challenge's stated objective is not financial success.
This will let us design Apocodes features, showcase them, and talk to customers.
(Edit: The first micro-SaaS was launched!)
Follow along
If you want to follow the story of Apocode or our progress in this challenge, you can subscribe here.
If you are interested in using Apocode, sign up here.
If you want to provide feedback, discuss the idea further or get involved, email me at nicolas.tresegnie@gmail.com
Scott Hickmann
3 years ago Draft
This is a draft
My wallpape
