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Category: Blockchain course in Brazil

Certification, The ends justify the means.

Certification, The ends justify the means.

The wild west of certificates

Blockchain education is a growing ecosystem with very few players. Most courses and training programs are trying to create their certification program, tailored specifically to their self-construct program. This is a major issue for anyone involved in this field: the students, the course/program instructors and creators and future employers/customers.

My experience in this ecosystem has let me consider few approaches regarding certification, especially my eight weeks live course which provided me with numerous insights and made me examine ways to evaluate the topics that the students are learning/need to learn, the exercises that they’re performing and the benchmark on which they’re tested.

 

The basic badge system I created for my course

Knowing that there’s a lack of standards in the ecosystem, I decided to create a badge system that will provide my students with some tangible results that are not necessarily tied to the course itself. If a student wants to prove to a future employer his or hers achievements, they can just show them the codes they’ve created and/or the transactions they’ve pushed to the Ethereum/Bitcoin blockchain.

Having that in mind, I created a certification system that was aimed to draw the students to achieve a specific goal. A goal that was set at the end of 4 “progression trees” where each tree was build to reflect the chronological/difficulty order in which the course topics should be taught.

The four trees are:

  1. Establish a connection to remote Bitcoin node –  Understanding the basics of working with the Bitcoin network.
  2. Transmit a Bitcoin transaction (p2pkh and op_return. p2sh transactions were considered for bonus) –  Mastering the concept of transactions, scripts, op_codes, utxo, fees, inputs/outputs, etc.
  3. Create a mock Bitcoin miner (build a mock block) – Consensus rules, Merkle trees, proof of work, difficulty/targets.
  4. write and deploy Ethereum smart contract.

However, while I’m highly confident that having a final product to show for is more valuable than (most) current certifications, I did want to provide my students with some more “traditional” certification, but still, one that directly reflects the students’ accomplishments.

The badge system as a map

The badges I created were used mainly as a top-down map helping the students (and myself) to keep track of our progress during the course and in that they’ve achieved their goal. However, these maps, being the top-down maps they’re didn’t gave much in what is it that the students actually know from a technical point of view (the codes that they’re using, the tools, the mathematical background, etc.) and in that regard, they’ve lost a substantial level of depth that might’ve been useful for potential future employers. At the end of the day, it’s not just enough to provide proof that you’ve managed to write and transmit a transaction to the Bitcoin testnet, it’s also important to have proper documentation on how you did so.

Another thing that was somewhat lacking is the finer way to assess students progression during each step because the final goal was the primary benchmark on which the students were tested against. If a student managed to reach the goal, he received the badge – no matter how he or she got there. Without going into the fairness of the process (Which btw, I consider entirely fair), it’s important to create a way to also evaluate students proficiency in each step leading to that final goal. This is particularly the case when not all of the steps are equally important in academic terms (e.g., If the goal is to create a mock block, then understanding how to build Merkle trees and finding their root is more important than just populating the block header, especially when we’ve created protocol messages in previous classes).

Another thing to consider is the importance of the tools that were used in the process. Creating, signing and transmitting a transaction is, of course, a great way to prove ones’ proficiency in Bitcoin and blockchain in general, but it is hugely different between doing so using JS libraries, python code with ECDSA and C. And the trees I’ve created don’t reflect that.

 

Open call for the ecosystem

At the end of the day, it all boils down to the fact that there’s very little cooperation between different blockchain educational institutions – both with each other and with the rest of the ecosystem. That leads to multiple certifications being issued without properly addressing the need of the rest of the ecosystem, and of the students themselves.

Those who are working on educating young programmers and developers should aspire to achieve a standard working conventions on which to build their courses. They should create a uniform benchmark on which to examine the student’s knowledge and a clear way to present it to future employers in a way that is meaningful. Claiming that the student completed course ETHD-15 should carry some extra information for future employers. They should know what is that the student learned, what tools did they use, how was the student tested etc.

I’m currently working to better define the topics that required from each type of developer/programmer, and the ways they can prove their skills in that topics and I hope that more will join me in this effort.

Bitcore.js keys for zeros and ones.

Bitcore.js keys for zeros and ones.

Bitcore is an excellent JavaScript library that is in use in many Bitcoin-related websites. Using the tools in this library one can easily achieve almost every Bitcoin functionality. Creating key pairs, parsing blocks, creating and signing transactions and more. In this post, I’ll focus on the use of Bitcore when dealing with key pair.

 

The zero

A beginner web developer can create a simple key pair by just using:

bitcore = require("bitcore-lib");
privateKey = new bitcore.PrivateKey // Generate a random private key
privateKey.toString()
>> "23bc740f87bd68729e794eb48b5137150f17109f855a34512c3c5f93d7498291"

The privateKey comes with ample of build in methods, most of which are more than enough for basic Bitcoin implementation in many web applications.

privateKey.toAddress().toString()
>> "1LY75mCpuD3xPfLLFwbWccBNoQQY4VBeQj"
privateKey.toPublicKey().toString()
>> "0379d42509499082436c89a4e1637ed14a27e56174843bddb980ab6f155f82431c"

This codes can be implemented in a manner of minutes. Bitcoin can be incorporated into many web applications in less than a day. However, those of you with a keen eye to Bitcoin protocol probably noticed that the public key comes in its compressed format. The uncompressed public key will be twice as long (64 bytes + 1 byte) and will have 0x04 as their leading byte.

This is, of course, a non-issue for most use cases, but it might be somewhat counterproductive when learning the relations between private keys, public keys, and address.

To truly understand something, there’s no better way than to get your hands dirty. And when we’re referring to something as crucial to Bitcoin (and blockchains in general) as key pairs, no shortcuts should be made.

 

To one.

During my first experimentation with this library, I received the impression that, as good as this library is, it might not be sufficient to teach and learn the underlying mechanism of the Bitcoin blockchain itself.

However, after more careful examination I came to realize that this library provides much more granular tools than what I expected. In fact, it seems that I can use it in conjunction to the developer documentation on Bitcoin addresses.

This is done thanks to one specific method that returns the numeric value of each point in the public key (don’t forget, the uncompressed public key is just a set of x-y coordinates).

publicKey.point.x
publicKey.point.y

This is highly useful method for a number of reasons:

  1. It creates a big number object in JavaScript, thus saves us from the hassle of working with 32+ bytes (A big drawback in JavaScript is the lack of native support for any number that is 32 bytes and above).
  2. Each point is given independently; as a result, the students are more aware of the real meaning of what a public key is really is (in terms of x-y coordinates). It’s also an excellent opportunity to show the students how one coordinate can be dropped to achieve the compressed address.

Another two very useful methods are:

bitcore.crypto.Hash.sha256ripemd160(pubKey);
bitcore.crypto.Hash.sha256sha256(hashedPublicKey);
The first two methods makes the hashing process really easy to execute. The Bitcoin protocol requires double hashing to be executed at two different locations in order to turn the public key to Bitcoin address. In many other languages (such as Python, which I've been using extensively when teaching this subject), there's a need to import and define each hash function. The process is tedious, and at the end of the day, somewhat messy.

By having these two methods, we save almost 40% in code space, and the students can focus on what’s really important in this lesson.

 

And here’s the final result:

// This code represents a possible approach for teaching Keys
// using JavaScript. 
// Pay attention that even while still using a JS library such as bitcore.js 
// The code still follows all the steps defined in the developers documentation.

bitcore = bitcore = require("bitcore-lib");

privKey = bitcore.PrivateKey.fromString("8c5e5b37ebf1e7a274b9dff4910f9a2004868897f7d845802b77a1b245c26bc7");

pubKey = "04" +
        privKey.publicKey.point.x.toBuffer().toString("hex") +
        privKey.publicKey.point.y.toBuffer().toString("hex");

pubKey = new Buffer(pubKey, "hex");

hashedPublicKey = "00" + bitcore.crypto.Hash.sha256ripemd160(pubKey).toString("hex");

hashedPublicKey = new Buffer(hashedPublicKey, "hex");

checkSum = bitcore.crypto.Hash.sha256sha256(hashedPublicKey).toString("hex").slice(0,8);

checkSum = new Buffer(checkSum, "hex");

binAddress = hashedPublicKey.toString("hex") + checkSum.toString("hex");

binAddress = new Buffer(binAddress, "hex");

address = bitcore.encoding.Base58.encode(binAddress)

 

Now compare to what we might see in Python:

Private_key = bytes.fromhex("BF9795D3FCB4E2181B7B536C2247EA0001397C99BA94D4D4DD62801BB151B091")

import ecdsa

signing_key = ecdsa.SigningKey.from_string(Private_key, curve = ecdsa.SECP256k1)

verifying_key = signing_key.get_verifying_key()

public_key = bytes.fromhex("04") + verifying_key.to_string()

import hashlib

sha256_1 = hashlib.sha256(public_key)

ripemd160 = hashlib.new("ripemd160")
ripemd160.update(sha256_1.digest())

hashed_public_key = bytes.fromhex("00") + ripemd160.digest()

checksum_full = hashlib.sha256(hashlib.sha256(hashed_public_key).digest()).digest()

checksum = checksum_full[:4]

bin_addr = hashed_public_key + checksum

import base58

FINALE_BTC_ADDRESS = base58.b58encode(bin_addr)

In this instance, we can see that the code created with bitcore js is much more straightforward and readable than even the simplest Python code.
This is a clear indication that using JavaScript can be a useful tool when teaching the basics of blockchain development.
The libraries can be used when teaching both web developers as well as more protocol oriented students. The code can be presented in highly simplified manner for beginners while still alluding
to its origin and the logic behind it.

Blockchain architecture and JavaScript

Blockchain architecture and JavaScript

Why (and why mot) using JavaScript

Many of my students wishes to create their own blockchain applications. Many of them came from app and web development background, and while they are still highly motivated to learn how the blockchain itself works, their main goal is not purely academic. They want to see a product in action.

When catering for such students, it’s important to adjust the course material to their own background and goals. Mainly it means to provide them with as many JavaScript tools as possible, as it’s the main engine behind many modern websites and apps.

Yet, adjusting the course shouldn’t come at the price of marginalizing the blockchain architecture itself. At the end of the day, the thing that separates such a course from millions of other web/apps development courses is just it – the blockchain.

Bearing this in mind should be a at the heart of every decision taken when creating and conducting such a course. And there’s a very little place for compromises.

This stunt approach led me to prefer teaching the students using more general programming language (mainly, python) while shy away almost completely from using JavaScript, which is fundamentally flawed for teaching protocols such as Bitcoin and the blockchain.

However, when done properly, a substantial part of the Bitcoin protocol can be explained, examined and tested using JavaScrips. And it’s important to develop the proper toolbox of JavaScript codes for that purposes.

 

// This code represents a possible approach for teaching Keys
// using JavaScript. 
// Pay attention that even while still using a JS library such as bitcore.js
// The code still follows all the steps defined in the developers documentation. 

bitcore = require("bitcore-lib");

privKey = bitcore.PrivateKey.fromString("8c5e5b37ebf1e7a274b9dff4910f9a2004868897f7d845802b77a1b245c26bc7");

pubKey = "04" +
        privKey.publicKey.point.x.toBuffer().toString("hex") +
        privKey.publicKey.point.y.toBuffer().toString("hex");

pubKey = new Buffer(pubKey, "hex");

hashedPublicKey = "00" + bitcore.crypto.Hash.sha256ripemd160(pubKey).toString("hex");

hashedPublicKey = new Buffer(hashedPublicKey, "hex");

checkSum = bitcore.crypto.Hash.sha256sha256(hashedPublicKey).toString("hex").slice(0,8);

checkSum = new Buffer(checkSum, "hex");

binAddress = hashedPublicKey.toString("hex") + checkSum.toString("hex");

binAddress = new Buffer(binAddress, "hex");

address = bitcore.encoding.Base58.encode(binAddress);

 

When to use JavaScript

The decision of when, and how to use these codes should be based on 2 main variables.

  1. What the students need to know.

The first one refers to the main reason the students came to the course. The more interested they’re in the blockchain itself, the more they can gain by working with languages such as Python/C++/go etc’. On the other hand, if applications is what they want to create, they can benefit the most by using JavaScrip.

Using JavaScript can be a great experience for them as they’ll both learn how to incorporate many robust libraries into their projects, but (maybe even more important), they’ll understand many of the limitations that surrounds JavaScript and its impact when creating a blockchain app. Limitations such as working on the client side, storing keys, accessing ssl, working with large numbers etc’.

2. What the students already know.

This one is quite simple, what’s the student background. If the student is more competent in JavaScrip, he/she might benefit more from adhering to JavaScript instead of learning another programming language.

 

Can blockchain really be taught using just JavaScript?

I’m still checking it.

I’m trying to migrate as many of the codes that are used for teaching the blockchain itself from Python (most can be found here) to JavaScript.

In the next few posts I hope to provide a more detail accounts on this project, in the hope that it might be more helpful to future students.

 

Mixing environments – Creating working environment for blockchain developers

Mixing environments – Creating working environment for blockchain developers

This article is part of a series of articles depicting my experience with creating and conducting an 8 week long blockchain app development course in Brazil.

 

What tools should be used when teaching blockchain

 

The term blockchain is often misused. Very rarely do people use the term blockchain to describe anything beyond a chain of blocks. A lot of the time when people talk about the blockchain and its application, they basically refer to a somewhat wide variety of technologies, architectures, tools and protocols that, once properly combined and implemented, creates that “blockchain” they are referring to.

When I created the course, it was obvious to me that in order to properly teach the students how to work with “the blockchain”, I’ll first need to spend a lot time dealing with many different technologies and tools. There isn’t just one blockchain IDE or concept to examine; rather there are quite a number of them. Take key pair for example; private and public keys are some of the most crucial (and known) features in many crypto-currencies and blockchains, but they are by no means specific to blockchains. Many people use key pairs off chain. The same holds for many concepts that are highly integrated into the common view about blockchains – Hashing functions, signatures (and keys), scripts and stack architecture, byzantine general problem, bytes codes, merkle trees, DAGs and more.

Each feature in the list above represent another tool/approach/use case/concept that stands by itself but is also crucial to creating what is commonly known as “the blockchain”. This fact posed a great challenge for me when I tried to create the course. It was obvious to me that the course is aimed at people who want to learn how to develop their own blockchain applications and solutions, which meant that it will require the students to get their hands somewhat dirty in codes, command line prompt, and different computational tools.

The challenge here lay in choosing the right tools to work with while remembering that each item on the list should be taught in a manner that is  adequate on the one hand, but without going to a level too deep and insignificant for the course on the other hand. It was also important that there should be a clear difference in the relations between the different and individual items.  I knew I wasn’t hired to teach the students how to program or how to work with different environments. However, making the assumption that they had adequate programming knowledge, enough not to require any introduction to that programing language/ environment/ tools seemed quite optimistic at best, and downright stupid at worst. This is even more so when dealing with a variety of different tools and languages.

I decided to do my best to choose the most user friendly working environments – even at the cost of efficiency and future usability.

Numerous developers have their own working environment. However, I was convinced that every code, example and CLI command/tool should be properly tested and documented in a single uniform environment. The last thing I wanted to do was stand in front of the class while in the background, my code failed to compile. The result of this is that I tried  a lot of different environments while always keeping in mind that the environment to be used should fulfill the following requirements;

  1. It needs to support all the tools I require that my students use.
  2. It shouldn’t affect in anyway the students’ computers, working environments, file systems, paths and/or jeopardizes their computer security in any way.
  3. It should be uniform for all the students.
  4. It should be easy and fast to set and reset whenever needed.
  5. It should be as user friendly as possible.

 

After a few experimentations, I decided to work with the following configurations:

 

  1. Cloud9 level 1 IDE environment with the following installations:
    1. Python-pip.
    2. Python-virtualenv.
    3. Virtual environments for Python 2.7 and 3.5
    4. Ethereum SOLC
    5. Tcpdump (for some reasons, not all c9 workspaces had it installed)
    6. The following pip packages (base58, ecdsa)
Cloud 9 was used for running python files and as a uniform terminal.
  1. Digital ocean Ubuntu 16.041 X64 droplet with the following installations:
    1. Nodejs 6
    2. Meteor Javascript framework version 1.3.4 with web3 and bitcore-lib packages.
    3. The following changes were optional for a few students:
      1. Installing ipfs and running ipfs daemon and adding ipfs-api package to their meteor app. (For those who wished to work with IPFS).
      2. Adding swap file of 4 gb. (For those with memory issues).
  • Use openssh. (More IDE flexibility for advanced users).

 

  1. Solidity browser compiler was mostly used for writing and deploying smart contracts. SOLC (installed on c9) was used by a few students who required some more advanced contracts (mostly when containing libraries).

 

  1. The only 2 components the students were required to install on their own machines were:
    1. Chrome/Chromium with metamask addon.
    2. Wireshark.

 

Cloud9 provided a well-tested and easy to configure working environment that was consistent for all students. It was used mainly to run the Python codes the students created, to compile some Solidity codes (using SOLC), to catch some packets using tcpdump (The tcpdump files were later downloaded and examined using wireshark) and to access digital ocean droplet using ssh.

I was very pleased with this working environment as it was quite robust, highly configurable, not local and easy to reset – Basically it was a great playground to get dirty with, without having to worry about damaging the students’ native environment.

 

Digital ocean droplets were used to provide the students with a uniform platform on which they can create their apps. Meteor is a well-documented JavaScript framework. It was obvious to me that if the students were expected to create applications, they should also have access to some JavaScript tools as both Bitcoin and Ethereum have some very powerful tools for app developers – mainly web3 for Ethereum and Bitcore for Bitcoin.

There’s also another npm package for compiling Solidity (similar to SOLC), but unfortunately, I’ve experienced a lot of compatibility issues with that package and decided to ban the students from using it. IPFS-api is another useful tool for more advanced students who are interested in working with IPFS.

It is important to note that although I did discuss IPFS with some students, I didn’t consider it an important part of the course. First, the system is still in a very early stage. Secondly, the main goal of the course was to teach the students how to develop blockchain applications, and not necessarily decentralized applications (although the two might have a lot in common, they’re not mutually the same) and IPFS just didn’t really fit the slot. Besides, I already had an ample amount of topics to focus on and teach my students (And I must admit; I’m not that much of an expert in this platform myself).

Another point to consider is that in a future course, in the case where there’s no promise to create apps, digital ocean might still be used. In this case, JavaScript libraries can be taught by using clean nodeJS interface.

 

Metamask and solidity browser were wonderful and very easy to use tools. In a manner of minutes, the student had yet another playground to play with Solidity and the Ethereum blockchain.

(It’s important to note that I took some time to make sure ALL of the students were using clean metamask installation WITHOUT any of their real wallets imported to it and only on the Ropsten testnet).

 

One last note about truffle

I also feel compelled to justify a little further my decision to exclude the use of truffle and/or embark (with testrpc) during the course and instead choosing to work with solidity browser compiler. The thing is,  at the time, both truffle and embark had some memory issues that forced me to use another swap file (both when tested on Cloud9 and when tested on digital ocean droplet). In addition to that,  most smart contracts required were easy to deploy from the Solidity web compiler. For specific ad hoc contracts that required the use of a more robust compiler, Ethereum SOLC was used on cloud 9 (SOLC didn’t had any memory issues). I do however recognize that truffle and embark are major tools in the industry and I’m defiantly planning to integrate them into future courses.

What to teach when teaching blockchain

What to teach when teaching blockchain

This article is part of a series of articles depicting my experience with creating and conducting an 8 week long blockchain app development course in Brazil.

 

The course as a mega structure

After I accepted to take on this challenge, the next logical course of action was to create the listof material I intended to teach the students. Originally, this list contained almost everything blockchain related – from bits, bytes and creating protocol messages all the way up to an overview of the history and politics of Bitcoin. The list was long, perhaps too long. I must admit my own limitations- I couldn’t see any realistic way to create such an extensive course by myself.

In addition, I had some doubts as to how many students can actually properly digest so much material, even when given 8 full weeks. (6 actually, if you count the time given to personal projects). I realized the list needed to be more focused – and that’s where my first major decisions were made.

 

Decision number 1: Focusing on the protocol itself. By deeply understanding the Bitcoin (and later the Ethereum) protocol, I believed the students will gain some clarity and very strong foundations upon which they can later build on and learn more extensively by themselves.

It was highly important to me to ensure they actually understand the protocol itself – how it developed, the tools it utilizes, and the logic behind choosing these specific tools and architectures and so on.

Once the students understood the intricacies of dealing with it, they will be better equipped to learn by themselves other things like how to use JS libraries in web applications; read and understand whitepapers and BIPs/EIPs, and create their own private chains and more. But how do I teach the protocol? That’s where my second decision was made.

 

Decision number 2: Bitcoin is the gold standard of blockchains and therefore, the go to chain when learning the basics of blockchains. This decision was a no brainer for me and represents a substantial chunk of my personal view on the blockchain ecosystem. The Bitcoin blockchain is the most widely used, heavily researched and extensively documented (albeit the documentation is somewhat lacking in my opinion). Every blockchain in existence this day stemmed from it and relies to a large extent on many of the concepts introduced by it.

It was clear to me that creating a blockchain course that isn’t based on the Bitcoin protocol will be a major breach of the faith the students reposed in me.

These two decisions brought with them peace of mind. Whereas before I was drowning in a pool of topics to cover – a list so long and chaotic, it was completely unmanageable, I now had a solid anchor to work with.

 

 

The four stages of mastering the blockchain

Once the list was completed, it became clear it could be divided into 4 main stages or phases:

The basics

From bit and bytes to protocol messages. The idea is that once completed, the student is able to send, receive and (maybe most importantly) parse a Bitcoin protocol message. In order to achieve this, the students will need to learn the basic mechanism of networking, create the byte code for a Bitcoin message – both payload and header, learn how to use one-way functions, hashing and how to read and understand the Bitcoin developers guide and protocol documentation.

Here, I held enlightening conversations with the students that revolved around keys. We went through the documentation together in a bid to learn about how to move seamlessly from private key to the public one and onto Bitcoin address.

Transactions

The bread and butter of the Bitcoin protocol. Now that the students have the understanding of how to work with the Bitcoin documentation, the next logical step was channeling that documentation and using it in creating transactions.

Here, the students will garner all their knowledge about bits and bytes, hashing and keys (from the previous stage) and channel it into creating the raw Bitcoin transaction. After which, they will learn about the pkScript; scripting in Bitcoin (and scripting in general) plus stack architecture and how the pkScript is executed, which by the way is also a great opportunity to start the conversation with the students about Ethereum and its virtual machine.

 

Finally, the students will go on to elucidate on what type of transactions are considered standard.

 

Blockchain architecture

After speaking with the students about all the basic components required in creating and transmitting a Bitcoin transaction, it was time to move on to talks about blocks and their architecture. I wanted them to have an understanding of what blocks really are. We were to create merkle trees (and merkle roots), blockheaders, calculate (mock) difficulty and target, and find the proper nonce. Along with that, it was also a great chance to have a chat with the students about DAG and consensus, mining algorithm, forks and altcoins.

In this phase, I was also afforded an invaluable chance to have a discussion with the students about contracts and secondary layers such as lightning network and BIPs (SegWit, addresses and other bips).

Ethereum

This is the second most predominant chain out there. It includes the wild west of consensus rules, mining algorithms and script (VM) playground. Many students want to understand how it works, and rightfully so. However, what most students want in learning Ethereum is how to actually use it – how to write smart contracts, and hence, how to use Solidity. This is where my previous decision to focus on Bitcoin as the gold standard for blockchain architecture became two opposite things; a blessing and a curse.

I wanted to spend as much time as I possibly could on Solidity, Web3 and Ethereum specific tools, and since I already spent more than half of the course talking about blockchain and Bitcoin, I was freer to talk about Solidity and web3 in this part of the course. However, a compromise was made and several unique architectural aspects of Ethereum were left out. I briefly talked about gas and the EVM by tying it to Bitcoin scripts and fees, and I glossed over block structure by simply stating that “merkle roots are also involved”. Mining and Ethereum attempts to move to POS were completely ignored – I think you get the picture.

The only architectural aspects of Ethereum I discussed in class were the ones that can be easily seen when playing with Solidity and smart contracts (Libraries and calls, Inline assembly, variables gas price, constant functions, variables scopes etc.)

 

I used this general scheme to select the topics to be covered in the Bitcoin part of the course

 

A sense of achievement

All in all, I’m quite proud of this structure and the topics it included. I found myself with a solid and detailed road map of the course. It was clear to me and to a lesser extent my students where we are now, and what is yet to come. I also hoped to use these 4 stages as the basis on which I would create semi-official certificates for my students. The idea was that every 1.5-2 weeks or so, the students did manage to achieve something very meaningful.

On completion of the first stage, the student managed to establish connection to a remote node on the Bitcoin network, and created key pairs and Bitcoin address.

On completion of the second stage, the student proved that he/she possesses a deep understanding of how Bitcoin transactions work. Things like how to hash a transaction, how to deal with TXID, how fees are determined, how (and when and where) signatures are used in the protocol and how the Bitcoin scripting language works. All of these gave the students a platform to create the bytecode for their own transactions (P2PKH and OP_RETURN).

At the time the third stage was completed, the students had managed to create their own block by creating the merkle tree and finding its root, calculating (mock) target, creating the blockheader and eventually finding the right nonce (Important note: I didn’t ask the students to create a coinbase transaction, although we did talk about it and examine its structure, but I believed adding another type of transaction will only serve to confuse them).

The final stage, the Ethereum stage, was in fact more of free working sessions. As I mentioned earlier, one of the requirements was that the students will have time to create their own dApps. Each student was working on his/her individual projects and as long as they managed to get their smart contracts to work, they managed to complete this stage.

(More details on my experience with the certification system in the coming articles).

 

 

So how did it go?

The first part of the course went rather smoothly, either because the students were still very eager to learn or because it was truly well constructed.

However, owing to some technical problems, I did not receive the certificates on time which placed me at a somewhat awkward position. Not only did I make a promise to my students that I’d give it to them, I was also quite worried that in the absence of something more tangible, they might not properly appreciate their own progress during the course.

This fear continued to be my shadow through the duration of the course as I tried to motivate my students to continue their hard and not so rewarding work. Right at the end of the course, I did manage to receive some documentation I could give my students and the response was very positive indeed. I’m now more convinced than ever that providing a proper certification at the end of each step can reduce much of the stress and hardship associated with such a demanding course. As a matter of fact, one of the major decisions I made at the end of this course was regarding certifications.

There was a major criticism I received during the course in relation to the course structure. A good number of the students, while not showing any major problem understanding the granular topic of the day and implementing the codes did have a hard time seeing the bigger picture. The structure I created aimed to look at the blockchain from a very close distance while working with some of its finest components.

I did try to encourage additional “free conversations” in class, hoping that during these less formal chats the students will utilize what we learned But soon it became clear to me that the timing of these free conversations, their length and their focus (or lack of it), was quite counterproductive. Therefore, I needed to come up with more appropriate time slots for such informal class sessions, while making sure to be well prepared with case study in case the students will not be focused. . For example, it might have been productive to try and talk about SigWit during the transactions class instead of only at the end of the Bitcoin portion of the course, even though the students didn’t yet learn about merkle trees, blocks architecture and BIPs.

The students were vocal about their desire for me to focus more on the big picture. This was in addition to some external pressure placed on me to start working with the students on their own personal projects. All of these led me to the production of some minor (yet quite meaningful) changes to the structure, mid – course. Basically, the border between the third stage (Blockchain architecture) and the fourth (Ethereum) was less strict than I wanted it to be.

It is true I already planned to use the third stage as a transition stage (as mentioned above, a substantial part of the Ethereum architecture was glossed over by comparing it to the Bitcoin blockchain). I did plan to talk about Ethereum quite extensively at this point (Ethereum was supposed to be mentioned first at the end of the second stage- transactions stage- right when the students learned some standard pkScripts). I still wasn’t well prepared with a suitable road map to make this diversion from the predefined curriculum.

The final result was that the transition from Bitcoin to Ethereum was lacking at best, if not somewhat confusing. This experience, while being somewhat hard in real time, did help to solidify my own confidence in the structure of the course – at least in its higher level and I’m much less inclined to perform similar deviations in future courses.

Another veritable source of confidence is the progress many students showed. A small, yet substantial, part of the class came on board with little to literally zero experience in programming and blockchains. Yet, by the end of it, I did witness some highly impressive progress in their abilities and understanding while the more advanced students also managed to create some impressive codes, smart contracts and even to construct a few apps. Ultimately at the end of the day, that’s what matters the most.

Teaching blockchain in Brazil

Teaching blockchain in Brazil

What is it all about

A few months ago, I received an interesting email from a company I didn’t know at the time. What was the content? I was asked to create and conduct a full fledge, 8 weeks long, blockchain development course in Brazil that would involve students from all walks of life.

Blockchain education is something I am passionate about, so this offer immediately struck a chord in me. In the past, I have talked a little on how I got into this field and given some insights on my views about the current ecosystem in terms of education. To sum it up; there’s an existing huge knowledge gap that serves to keep many talented people from properly contributing and utilizing numerous blockchain based solutions.

The deep-seated desire to bridge this gap is a major part of my personal agenda. For that reason, in the past, I created a few videos and tutorials (which owing to the fast paced nature of technology are in sore need of an update, I know) that were aimed at mitigating this gap in knowledge and making blockchain codes somewhat more reachable for developers and tech people who are new to this ecosystem. In addition, I was looking for other ways to bring Bitcoin and Ethereum to the people. In line with this, a creating/conducting course seemed like the logical next step.

In the early chats that transpired between me and the Brazilian company, I was offered the freedom to construct the course as I see fit, without any restrictions.  There was one specific request – that when the duration of the course comes to an end, the student will create their own apps. Considering the proposed length of the course (8 weeks), I believed  it would be quite easily achievable simply by allocating the last 2 weeks of the course to exclusively working with the students on their personal projects.

As we talked about the projects the students might create during the course, we also discussed the lack of needed quality in many of the current blockchain related projects out there.  I gave my impression that it was due to a dearth of understanding of blockchains. Most projects are nothing more than basic apps that have very little to gain from using the blockchain and are either utilizing it for marketing reasons – basically to draw more investors’ money owing largely to a lack of understanding on the investors’ side.

But this is not all; it could also be as a result of a serious flaw in their understanding of how to use the blockchain from the creators’ side. I wanted to ensure the students really have an understanding of what the blockchain is, and equally important, what it isn’t.

My counterpart was impressed by this approach and it became clear to the both of us we were seeing eye-to-eye on what our vision for the course was.

 

Getting ready

Working on the course took a substantial part of my time for the better part of 2-3 months. I basically started creating a course from scratch as there were very limited resources and existing courses to draw from. I created a course structure, list of topics, codes and other teaching aids. The task was a hard one, harder than I initially anticipated. I basically, single handedly tried to create one of the most ambitious courses using nothing but my own means and with literally no support of any kind. But I made it!

Slowly but surely, I managed to create a list of working codes to teach my students. I had a solid course structure, the basic infrastructure for a certification system, few assignments, list of resources, presentations and a lot of notes – all corresponding and completing each other, tested and organized for maximum effect.

 

In Brazil

It was finally the moment of truth. I arrived in Brazil with my course (mostly) neatly organized and prepared. The time for theory was past and it was  time to see it in real action and put my work to the ultimate test.

 

Some curious Brazilian horses that participated my class.

 

The final experience in Brazil was much more challenging than I thought it would be. Some of the difficulties I encountered were related to the technical background and level of the students (the class was very heterogeneous). While some had extensive experience, others had absolutely zero previous experience.  A number of the challenges were related to my own preparation for the said course.

Still, when the course winded to an end, I was highly pleased and proud to see how ALL of the students managed to show great advancement.

I’m very grateful for this experience. I had the opportunity to create a full fledge course, a unique and solid one that provides substantial blockchain education, an element that is sorely lacking outside of very specific programs in selected universities. The challenges I encountered during the course were also a great blessing; my course (and by extension, my whole approach to blockchain education) was tested rapidly and almost every aspect of it was subjected to stress test, and it made it through!

Additionally, this course was a great learning experience for me. As a matter of fact, I’m already working on implementing some of the things I’ve learned in order to provide even better learning resources and courses in the near future.

Now, almost a month after the course, I decided to sit down and articulate my thoughts and experiences. It is my wish to share what I did and what I learned. It is my hope that by doing so, I might be opportune to effect some positive impact on the blockchain education ecosystem and that these articles will be helpful to many.

The articles are currently divided into 7 major categories:

  1. Course structure.
  2. Choosing the working environment.
  3. The codes that were presented and exercised.
  4. Certifications and accreditation.
  5. Teaching aids.
  6. Assignments, homework and evaluation.
  7. Others (students’ background, learning environment, marketing and setting expectations, class size, after class meetings etc.).

These articles will be published in parts in weeks to come.