Cloud Mining 2019 or How to Make $500 from $100. Is it possible?

  • Denys Serhiichuk
    📚 WikiCoin

    💲🖥️💲If you do not have a chance to buy hardware, but still want to mine Bitcoin or Ethereum, then cloud mining is the best chance for you. Today, there are lots of services which offer it, but not all of them are reliable ones. IQ Mining is one of the popular and trusted ways, taking into account feedback. In this article, we will analyze this cloud mining platform and tell you how to make a profit from it

Cloud Mining 2019 or How to Make $500 from $100. Is it possible?
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Disclaimer: The opinion expressed here is not investment advice – it is provided for informational purposes only. It does not necessarily reflect the opinion of U.Today. Every investment and all trading involves risk, so you should always perform your own research prior to making decisions. We do not recommend investing money you cannot afford to lose. 

The topic of cloud mining has been relevant for a long time and the more interest investors show in it, the more projects appear that end up with the disappearance of its leaders along with the money of the clients. Among the cloud mining services, unfortunately, there is a huge amount of scams and you should be extremely careful when choosing a company. However, IQ Mining, one of those teams that consistently pays mined cryptocurrency, has established itself as a decent and proven service. If it was not so, it would simply not exist for as long as it has.

The right approach to choosing a reliable cloud mining service

First of all, you should look at profitability. Although cryptocurrency earnings are considered a highly profitable business, a reliable company will not promise more than 300% per annum. If you see inadequate numbers, then most likely there is a HYIP in front of you, which is disguised as a cloud mining site.

You also need to pay attention to the commission of a service. It is clear that no one will work for you for free. Thus, the lack of maintenance fees for the equipment is also an alarming sign. It would not be superfluous to read reviews about the selected site, especially if you are going to invest a large amount.

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Basic service requirements:

  • Favorable rates. The cost of purchasing capacity is very important, as it greatly affects the rate of return on investment.

  • Reliability. The most important service requirement. There are many fictitious services that disappear with your money.

  • Real equipment. The service can guarantee payment of money only if it has its own equipment for mining.

  • Convenience. Various additional options that increase profits and the usability of the service.

What is IQ Mining

IQ Mining is a company that provides cloud mining services, has been operating since 2016 and allows investors to rent cryptocurrency mining equipment. The main packages offered for rent imply multi-currency mining, within the framework where capacities are automatically switched between the top 10 coins. The legal address is registered in Seychelles, but data centers are located in different parts of the globe (Asia, Europe, Middle East). The main feature of the service is a smart algorithm that independently determines the most profitable asset at the moment and directs all purchased capacities to its mining.

The official site of IQ Mining is available in several languages and allows users to immediately find out the amount of monthly income, calculated in accordance with the amount of investments.

IQ Mining logo

Features of the project IQ Mining is the one and only official website of the company.

The methodology of the IQ Mining platform to the setting of cloud mining is very different from the standard remote service that most virtual data centers offer us. And here are its highlights:

  • IQ Mining is based on the mining innovation, where the hardware autonomously selects the most beneficial altcoin at the moment and continually changes between them to get the greatest benefit. And after mining is done, all earnings will be converted into Bitcoin.

  • Service has established lucrative cooperation with international players from such countries as: the Russian Federation, Georgia, Canada, and other states to utilize their surplus power from high-quality hardware. Wholesale rates and delivery times of capacities are protected by lawful contracts, which allows extracting more profit than other mining platforms.

  • An important feature is the availability of user-friendly analytical tools on the site, including a calculator, which will help you quickly navigate the choice of contract, help you manage the payback period and show the amount of profit of your activity.

  • You can deposit and withdraw money without commissions.

You can start mining cryptocurrency with only 10 dollars. The whole point of your business is as follows: you simply invest money and get income depending on the size of the investment, and the software algorithm independently performs productive mining for you.

Profitability of IQ Mining

The site gives the opportunity to mine 5 cryptocurrencies: Ethereum, Litecoin, Zcash, Monero, and Dash. The crucial thing affecting client benefits is the hashrate (leased capacity), but in addition to it, profitability is influenced by:

  • Availability of privileges and bonuses – it is known that there is an IQ Mining promotional code offering a discount on the first contract, and other promotions for clients are being held.

  • Financial management – buying of an additional hashrate power for already-mined coins.

  • Cryptocurrency value – the more costly digital assets are traded on exchanges, the more the client will obtain.

  • The platform only offers 1-year fixed-term contracts.

The price of a lease is determined per unit of hash power for a specific algorithm.

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What is the concept of the IQ Mining service?

The company optimizes the cost of electricity. The work with TOP electricity suppliers helped to achieve this. The service works in an understandable way: altcoin mining is launched, IQ mining sells them, the customer gets additional profit, which is transferred to his crypto-purse or another convenient payment system.

Some peculiarities of the platform:

  • IQ Mining operates by leasing excess capacity in the largest data centers. This allows you to mine 2-3 times cheaper.

  • The smart contracts contain the terms and prices of the supplies.

  • Despite the fact that the altcoin mining is considered to be very profitable, it is among the riskiest, since price fluctuations are frequent and constant. In order to at least somehow secure your investments and earnings, IQ Mining converts altcoins into BTC at the best rate. This is made possible by special limit orders that are set up on crypto exchanges with low spreads.

Comparing IQ Mining with other cloud mining platforms

IQ Mining

Other Cloud Mining Platforms

Simultaneous mining of several prospective coins

Mining of only one cryptocurrency for one contract

Constant monitoring and automatic shutdown of low-yield cryptocurrency mining

You are forced to continue mining altcoins, even if its rate falls

There is no risk from price fluctuations on altcoins. All payments are made in Bitcoin

Market prices for altcoins can significantly affect the income of the miner

No hidden fees and maintenance fees for maintaining a client account

Availability of commission and service fees

How to start cryptocurrency mining with IQ Mining

Getting familiar with the website

The service has a rather pleasant website with an intuitive interface. The site is available in Russian, English, Spanish, French, German and Portuguese. We are met by two buttons: “start mining now” and “mining calculator”. The first will allow you to register, the second will help calculate the possible profit.

IQ Mining website interface

On the main page, we get information about the company, its current offers, and current prices. In the “Pricing” section there is a convenient online income calculator, and by moving the slider we can find out the estimated income for different periods of time.

Possible income calculation

If you have additional questions about the service, it would be convenient to look into the FAQ section where you can find answers to many issues.

So, we have decided to invest. Let’s get down to business!

IQ Mining Registration

By clicking on the button “Start mining now” or “Sign up”, a pop-up window appears in which you should enter the registration data: name, phone, email, and password. Enter the necessary data, tick off the agreement with the rules of the service that you are not located in the United States and click “Register”.

 IQ Mining registration page

Confirmation of Registration

Several emails will be sent to your email account. The first letter is a registration confirmation; it will contain a link to your personal account, as well as a login and duplicated password. The second letter is a greeting from your personal manager with his contact information.

Do not be surprised if sometime after the registration you will be called on VIBER from an unknown phone number, as this is also a service manager of the company.

In order to get full-fledged access and the ability to deposit and withdraw funds, the service will ask you to provide copies of documents for account verification.

IQ Mining verification procedure

After registration, you will be forwarded to your personal account where you can purchase the necessary MH/s for mining cryptocurrencies. Further on this page, you will be able to keep track of your capacities and profits, where you will also be able to buy additional power.

Personal account interface

By clicking on the “Buy More MH/s” button, we move on to the already well-known online power calculator, which will allow us to visually understand how much we will earn when we make a specific amount.

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Variety of contracts

The interface is replete with buttons that move the user to the hashrate purchase page to start receiving passive income.

The process of ordering the contract looks like this:

  • Specify the required capacity: enter the amount manually or by moving the corresponding slider.

  • Familiarize yourself with the value of the payment.

  • Decide on the payment system (you will see the available options at the bottom of the screen).

In general, there are no difficulties with the purchase of contracts, even for beginners. The interface is well thought-out and intuitive.

Depending on the amount you wish to invest, the system will automatically assign a maintenance rate. There are three tariffs: Bronze, Silver, and Gold.

Everything is quite simple: the more you invest, the cheaper the power will cost you, and less will be the commission of the system. Accordingly, you earn more by investing more money.

IQ Mining contracts

Bronze tariff

Payments in this tariff are made daily. In the mining process, the Script algorithm is used. The cost of 1 MH s is $5. Commission maintenance costs reach $0.005 / 1 Mx/s /24 hours.

Silver tariff

From 300 Megahash per second. Crypto assets are paid on a daily basis. The digital currency is mined by the Script algorithm. For 1 MH s you will need to pay $4. Maintenance fee is $0.003/1 MX / s / 24 hours.

Gold tariff

From 3000 Megahash per second. Funds are transferred to the user's wallet every day. 1 MH/s costs $3 in this tariff. Crypto is mined on the Script. Maintenance fee is $0.001/1 MX / s / 24 hours.

Based on the available tariffs, we can conclude that when buying a Silver package, you can fully return the investment:

  • With Bitcoin – after 11 months

  • With Litecoin – after 12 months

  • With Ethereum – after 15 months

  • With Zcash – after 24 months

Account deposit

After choosing the desirable tariff, the new user will need to make a start-up deposit to his balance. This is necessary for the buying of hash capacities and to start working. The software of the service allows the deposit using the following methods:

  • Visa / Mastercard

  • Bitcoin

  • Ethereum

  • Litecoin

  • As well as 12 other cryptocurrencies (BCH, BLK, BCN, DASH, DOGE, EMC, PPC, XPM, RDD, ZEC)

The minimum deposit is 0.01 BTC or an equivalent amount in another currency. Full information on all deposit and withdrawal operations is located in the personal account.

Once you have deposited the account with your own funds, you will have to purchase hash powers. What volume to buy depends on the preferences of the user; in fact, the larger the investment is, the higher the future profit will be.

Funds deposit at IQ Mining

IQ Mining opens up an additional opportunity for users to increase their earnings. To do this, you must reinvest the profit in order to expand the original contract. This will allow the clients to significantly increase the level of profitability from cooperation with the service without buying additional contracts.

Funds withdrawal

Regardless of the service tariff chosen, you can withdraw funds daily. Your income will be displayed on your balance, changes are recorded every hour.

  • The minimum amount for withdrawal is 0.001 BTC.

  • Bonus. When purchasing capacity, you will receive a bonus of 10 to 20% of the replenishment amount if you deposit from 0.1 BTC.

  • Registration in the system is free of charge, there is no subscription fee.

  • You can apply for withdrawal at any time of cryptocurrency mining.

  • In addition to Visa/Mastercard, you can use Webmoney, Mastercard, Yandex Money and other electronic wallets for withdrawal.

Deposit and withdrawal limits:

  • Altcoins – from $10

  • Bitcoin – from 0.001 BTC

  • E-wallet payment – from $10

  • Bank transfer – from $50

  • Transfer by credit card – from $25

IQ Mining payback

Here are examples of the paybacks of some IQ contracts.

IQ Mining payback examples

Technical Support Service

Even cryptocurrency experts can sometimes have questions about the use of the IQ Mining service. In this case, the specialists of the technical support team will come to the rescue. The service works 24/7, and it can be contacted either by email or via live chat. The platform has at its disposal an international team of specialists, so the user is not in danger of facing a language barrier.

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Summing up

In theory, the cloud service IQ Mining offers a very interesting way to mine: mining cryptocurrency coins in leased facilities. You do not need to invest thousands of dollars in high-performance and expensive equipment, provide it with ventilation and turn your house into a mining farm.

The main advantage can be considered the use of the algorithm to automatically search for the most profitable digital coins.

You do not have to pay large utility bills for electricity. All you need for cloud mining is to pay in advance a known amount for the selected contract and receive your income an hour after the start of mining.

How is cloud mining better than classic mining?

In the case of the purchase of conventional farms for mining, or especially ASIC-miners, a number of problems need to be solved:

  • Accommodation. Miners are quite noisy devices and placing them in residential areas will bring a number of inconveniences.

  • Cooling. In connection with the round-the-clock operation, miners need good cooling, due to which their service life is increased.

  • Electricity supply. One mining farm consumes about 1.4 kW / h, which requires high-quality wiring in the room. When installing more than 3 miners, the question of a separate line arises, since standard household lines are not designed for power above 4-6 kW.

  • Service. Miners periodically lag, they need to be configured for maximum speed and dedicate them a certain time.

  • Breakage. Most mining farms are not covered by the warranty, so a farm breakdown can lead to a crash. Cloud mining deprives you of all these inconveniences.

Principles of cloud mining

Companies offering cloud mining of Bitcoin are big data centers: they have developed infrastructure, low-cost electricity, and maintenance of multiple devices by highly qualified specialists. These are the distinctive features of real companies.

The capacities of cryptocurrency cloud mining services are based in areas with low electricity tariffs. Usually, data centers are located in the northern territories with natural cooling.

Companies are interested in providing large volumes of capacity. Delivery of equipment for rent allows you to buy additional devices, pay for electricity. Integration makes it possible to increase speed and calculate more blocks. This gives revenue to the service and customers.

There are different conditions for leasing capacity. But as a rule, the principle of cooperation with companies is the same. The client pays one of the tariffs.

The more hashes bought, the more coins received. Contracts are bought for different terms (24 hours, 1 year, 5-10 years). At the end of the capacity period, it is possible to sell it to the company at a reduced price (equipment wear is taken into account) or to other users at a contract price.

Experts believe that cloud mining in 2019 is a good alternative. To build a performance-efficient farm for Bitcoin mining, it takes more than one thousand dollars.

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Features of cloud services with bonuses

Cloud mining without investments is possible thanks to the free hashrate and bonus cryptocurrency, which is exchanged for computing power. Some cloud services hand out this hashrate for registration, so it’s not surprising that they are of more interest to members of the cryptocurrency community, as well as those wishing to penetrate into a niche.

  • First, getting a bonus, albeit a small one, is always a pleasure.

  • Secondly, thanks to the free hashrate, you get the opportunity to get acquainted with the capabilities of the service, and in general with a similar type of coin mining.

  • Thirdly, with the purchase of serious power, the bonus will not disappear anywhere, but will only complement them, which is also good.

The process of mining on cloud services without investments is presented in the following form:

  • Registration on the platform

  • Mailing address confirmation

  • Exchange bonus coins for power

  • Start of cryptocurrency mining

In principle, on cloud mining services that require investments, this process is similar, except for the fact that you will acquire power not for a free hashrate, but for your own money.

Disclaimer: The opinion expressed here is not investment advice – it is provided for informational purposes only. It does not necessarily reflect the opinion of U.Today. Every investment and all trading involves risk, so you should always perform your own research prior to making decisions. We do not recommend investing money you cannot afford to lose.

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How to Learn Solidity and Start Blockchain Programming

  • Eric Croix
    📚 WikiCoin

    If making an Ethereum-based dApp or creating an ERC20 standard token sounds compelling to you, than you need to learn the language called Solidity. In our tutorial we provide you with the foundation of coding smart contracts

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Blockchain programming has become one of the best paying and challenging software spheres during the recent decade. Although blockchains are language-agnostic and many of the existing languages, like C++ and JavaScript (JS), are used by blockchain engineers, there are some tasks that couldn’t be conveniently realized by existing languages, which opened up the demand for new, crypto-specific options. One such language is Solidity.

Solidity was born as a core part of the Ethereum ecosystem. It absorbed C++, JavaScript, and Python. It has many contemporary features like libraries and inheritance. Solidity is designed to write programs that interact with Ethereum accounts, which are called smart contracts. Smart contracts are executed on Ethereum Virtual Machine (EVM), enabling users utilizing them perform tasks like crowdfunding, blind auctions, voting, and many others in a decentralized manner. The most famous killer-app of smart contracts was decentralized funding in ICOs, which started the bull rally on the crypto markets in 2017.

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Whether you are an experienced developer or just starting out in crypto, it’s a good idea to start learning Solidity because smart contracts have become a crucial part of the blockchain ecosystem. Aside from being actively implemented by dApps, they are being actively integrated into infrastructure-layer blockchains and even in Bitcoin via providers like RSK. By knowing how to build smart contracts you will make your blockchain career more sustainable and be able to produce better quality solutions. Let’s not pull it off any longer and get our hands dirty with coding!

Understanding the basics of a smart contract

A smart contract account consists of three sections: balance, storage, and code. The balance represents how much Ethereum a smart contract has. Storage holds data like strings and arrays that are specific to an application. The code section has the raw machine code that is compiled from what we write in Solidity.

Unlike user accounts, smart contract accounts are not external to the respective networks. In other words, you can use your wallet with various networks like Kovan and Ropsten, but you can’t do this with a smart contract. Smart contracts are internal.

Each smart contract has a source, which is stored on an author’s device and instances, which are stored on the blockchain. In order to create an instance (account) of a smart contract, we need to deploy it to the network. It very much resembles the relationship between classes and instances in traditional object-oriented programming (OOP) and languages representing it (JS, Ruby). To give you a more visual representation, let’s create a class ‘Bike’ and add an instance of it.

Bike class & instance

Bike class & instance

Source: Image by U.Today

What we will be writing is a contract definition, which will then run through a compiler that will produce two files: bytecode and application binary interface (ABI). Bytecode is what will be actually fed to the EVM and ABI is a layer between bytecode and regular JavaScript code that allows building a user interface (UI).

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Choosing an IDE & version of Solidity

Before we start, we need a proper integrated development environment (IDE). In other terms, we need a convenient terminal with the necessary tools to write our code in. For the purposes of this tutorial, we will pick Remix, an IDE created by the Ethereum foundation that allows writing, testing, debugging, launching smart contracts and many more. You can use it either straight in the browser or download it locally if you would like.

Once you launch Remix, you will be presented with the code editor in the center, the file manager on the left, and a compiler on the right.

Initial Remix window

Initial Remix window

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There will be some pre-written code – we won’t need that. To create out first-ever smart contract let’s press on the little plus icon in the top-left corner of the terminal and give it a name.

Creating a new project in Remix

Creating a new project in Remix

Source: Image by U.Today

As we have the blank .sol document now, we should specify the version of Solidity that the compiler will run. At the time of this tutorial, the latest version is 0.5.7. If you are not sure which version to use, you can specify a range of versions.

2 types of specifying the version of Solidity

2 types of specifying the version of Solidity

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Lastly, let’s give our smart contract a name, followed by a parenthesis.

Smart contract naming

Smart contract naming

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Writing your first smart contract

Once we have our canvas ready, it’s time to define the basic building blocks – variables. While experienced software engineers will have no issues understanding this concept, we will briefly introduce it to beginners. Variables are placeholders for chunks of information that are later referenced by a program that runs them.

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Let’s create a couple of variables: a string (a sequence of symbols) and an integer (a number). In Ethereum’s case, variables are stored in the blockchain along with the rest of parts of contracts and can, therefore, be accessed and updated from anywhere. Another key characteristic of Solidity variables is that you can make them private by writing ‘private’ next to the variables. Finally, for the integers, Solidity has two types: signed (can be positive & negative) and unsigned (can only be positive). To specify an unsigned variable, we should just put ‘u’ before it.

A private string and an integer

A private string and an integer

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Once we have the ‘name’ variable, we need to write out the methods of setting and getting it. This looks like a JS function. Remember that Solidity is statically typed, so we have to define variable types. Now any value we put in the ‘setName’ will define the ‘name’ string. For the getter, we will use ‘getName’ and specify what variable we expect to see. Now, it’s time to do the same for the ‘age’ variable. The method is constructed similarly to the ‘getName’.

Name/age setters and getters

Name/age setters and getters

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Let’s test our little chunk of code. Go to the ‘Run’ tab of the compiler and press ‘Deploy’ under your contract’s name. At the very bottom of the compiler, you will now see the ‘Deployed Contracts’ section that has our methods available. In order to pass a name to the ‘newName’ value, we need to make sure that our string is written in JSON, otherwise, the ‘getName’ will return nothing. For the ‘setAge’ just put your age without quotes. As you see, we can now set and receive the ‘name’ and the ‘age’ variables through our smart contract.

Compiler, with a name and an age

Compiler, with a name and an age

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Defining Wei and Gas

One of the most remarkable features of smart contrasts is that to deploy them to the Ethereum network you will need to initiate a transaction, which costs some amount of money that is paid in Ether. It’s crucial to understand how the fees are utilized in the system, as they will be deducted each time you interact with EVM.

What’s Wei?

Let us assume that reading this far into our tutorial you have used Bitcoin at least once. You probably made a small transaction that was way less than 1 BTC. In that case, you used Satoshis, which are something like pennies for a dollar. Wei is like a Satoshi – it’s the smallest part of 1 Ether. If we think of it in programming terms, it’s the lowest unsigned integer in the network. While interacting with the network, you will mostly encounter Gwei, which refers to Gigawei and equals 1 billion Wei.

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What’s Gas?

Gas is an essential part of the mechanism of smart contract execution. It has two values for each transaction: Gas consumed and its price. It’s worth mentioning that a user initiating a transaction defines these values. However, if the set value of Gas won’t be enough to process a specific operation, then the Gas will be consumed, but the transaction will fail. Moreover, if the price for Gas will be set too low for the network at a given time, the transaction will not be processed by the nodes, eventually making it unsuccessful. There are several services to check optimal values for your transactions, one of them being To get a better understanding of Gas and why it costs any money, let’s code some of it by ourselves.

Get back to your Remix window and initiate a new file. In our example, we will call it ‘Gas’ and create a contract with the same name. Bear in mind that the more data we will require to store on the blockchain, the more Gas we will need. That being said, for the purpose of this tutorial we will create a cheap contract; the more you will add to it, the higher the fee will be.

There will be a function that returns an integer that is a sum of two inputs. To make it as lightweight as possible, we will specify that our contract will store nothing on the blockchain, and for that we will put ‘pure’ next to the function.

Cheap contract

Cheap contract

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Now you can deploy it in the compiler and input any two numbers to get the integer ‘c’. To check the price of our transaction we should take a look at the terminal located beneath the code section. There is a transaction cost and an execution cost. The first one refers to how much data a transaction has. The second one refers to how much of EVM’s power was required by the transaction.

Cheap contract’s cost

Cheap contract’s cost

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This is an extremely basic transaction that costs almost nothing for the network. In writing meaningful smart contracts you will add more details, which will increase their weight and therefore transaction fees.  

Creating & deploying your own ERC20 token

Let’s face it, the majority of the blockchain developers that are just starting out are eager to play big and create their own blockchains and tokens. While this is an extremely difficult topic that attracted some of the best software engineers from other spheres, building a basic ERC20 token isn’t rocket science.

First, we need to create another file in Remix and uploading the ERC20 interface, which is the following:

ERC20 standard

ERC20 standard

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The ‘totalSupply’ function lets us see how many tokens we have in total. The ‘balanceOf’ function is used to get amounts of tokens on specific addresses. The ‘transfer’ function allows users performing transactions between each other. The ‘transferFrom’, ‘allowance’ and ‘approve’ functions are there to allow people to let some other users initiate transactions on their behalf. Events are the logging tools for the ledger.

In addition to the interface itself, we will need a separate .sol file for our new token. Here we will import the ERC20 interface and specify our token’s symbol, name, and decimals.

uToday token

uToday token

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Before we compile it, we need to specify constraints.

  • Let’s start with the total supply – it’s a constant integer variable that we will make private. The total supply of our tokens will be 1 million, we also write a function to return this value.

  • Second, we need to store our token somewhere. For this, we will need to outline the mapping that will return a balance for any address specified.

  • Third, there should be a function for token transfers, which will essentially have an address of a receiver and an amount of token transferred. This function should also be able to check whether or not a sender has enough tokens on their balance, which can be realized through a simple if/then statement. In addition, we will set conditionals for ‘_value’ in a way that blocks users from sending transactions with 0 tokens as this would only flood the network with junk.

  • Fourth, we should create the mapping for the remainder functions, which is a mapping of mapping to an integer.

  • Then we will specify a few checkers in the ‘approve’ and ‘allowance’ functions and put conditions for the ‘transferFrom’.

  • Finally, not all the tokens will be available on the market. Some of the tokens are usually left out for teams, foundations, advisors and other purposes. Hence, it’s essential that we make it clear how many tokens will be circulating. As we created the tokens, the circulating supply equals our balance.

uToday token constraints

uToday token constraints

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The code is ready, so let’s test it. Proceed to the ‘Run’ tab of the compiler and deploy our token contract. You will see that we have our token data along with the total supply, balances, and allowances. Congratulations, you deserve a pat on the back!

To make our token actually function on the network, we need to deploy the smart contract (note that this is different from deploying it for testing in Remix). For the sake of this tutorial, we will use Remix and Metamask, but there other ways of doing so. Metamask is a simple but efficient Ethereum wallet program with a nice UI that integrates as an extension to some of the most popular browsers. In our case, we will use Opera. Firstly, go to and download the extension. Once it’s done, you will see a fox icon in the top right of your browser.

Downloading Metamask & location of the icon

Downloading Metamask & location of the icon

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Press on the icon and proceed through the offered instructions to create a wallet. Do not forget to store the secret phrase! When you have your wallet, press on the Metamask icon and change the network to ‘Ropsten’ because we don’t want to mess with Ethereum’s mainnet.

Changing Metamask to Ropsten

Changing Metamask to Ropsten

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The last step is to generate some Ether (unfortunately, you won’t be able to use these for any real purchases, but they are necessary for testing). Head over to and request 1 Ether.

Now you are all set. Return to your Remix window and change the environment to ‘Injected Web3’ in the compiler. Take a look at the account tab too – your address should be the same as that of what you generated with Metamask. Select the smart contract you want to deploy, which is your token contract and not the ERC20 interface and press on the respective button. A Metamask window will pop up with a transaction, its details, and options to interact with it. Submit the transaction, and our token will come into life.

Metamask popup

Metamask popup

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You can now play around with all the functions we specified earlier. Let’s look at our contract from another side to verify that it works properly. Like any other blockchain, Ethereum has multiple block explorers which serve the essential purpose of monitoring what’s happening on the network. In our case, we will stick to etherscan, though there is a handful of other great alternatives. Note that if you just go to etherscan, you will see the Main network. As we need to see the Ropsten network, you will need to put ‘ropsten.’ before the website’s address. Search for your address and you will see two transactions – one is for free Ether you received, and another is for deploying the contract.

User’s address in Etherscan

User’s address in Etherscan

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To find the address of your contract, press on the TxHash and navigate to the ‘To’ field. Here you can check your smart contract’s transactions, code, and events. At this point, we need to verify and publish our contract. Go to the ‘Code’ section and click on the ‘Verify and Publish’ link. Here you will need to again specify the name of your token, the version of the compiler (in our case the latest version of Solidity we used was 0.5.7, so we will stick to the related compiler version). Now you should copy the token’s smart contract code along with the ERC20 interface code from your Remix window to etherscan and press ‘Verify and Publish’ at the bottom of the screen.

Verifying the smart contract

Verifying the smart contract

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It’s time to go back to your contract’s address. The code in the ‘Code’ tab will now be verified. In addition, you will now have two more tabs: ‘Read contract’ & ‘Write contract’. In the reading section, we can check the functionality of our token. Input your (not the contract’s) address into ‘balanceOf’ field to see how many tokens you have; it should show 1 million that we hard coded as the total supply and gave it circulating to our wallet. That means that our token is now correctly working on the testnet.

Receiving the balance

Receiving the balance

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If you are looking to start a career in the crypto industry, you need to understand that despite its relative simplicity in basics, blockchain has incredible deepness to it. Since 2017 blockchains have evolved significantly and their use cases went beyond just financial transactions. With the advent of Ethereum, a whole new layer of networks appeared that hosts various dApps and blockchain-based solutions. The tool behind this evolution was a smart contract, and if you want to make your experience more valuable and future-proof, you should know how one works.

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While you can code smart contracts using other languages, Solidity is a better fit for such a purpose. Moreover, if you want to become an Ethereum developer, or create an ICO/ERC20 token for your project, this is your go-to choice. If you had some experience with C++ or JavaScript, coding on Solidity should be relatively easy. You will have to understand some differences between the client-server and decentralized models of launching software, though. Thanks to Ethereum Foundation and some third-party organizations, developers are presented with a set of convenient tools like Remix and Etherscan to code and deploy smart contracts.

We hope that our tutorial helped you with getting around the majority of Solidity’s concepts to be able to start your blockchain journey. Remember that you can always check with the latest documentation on Solidity. We wish you good luck and will be happy to use some of your dApps someday!

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