Register for our upcoming webinar:  

Why Tech Screening Fails to Uncover True Talent

Thursday | May 30, 2024 1pm ET

Register Now

How To Hire A Blockchain Developer

Blockchain developers can create and deploy smart contracts, self-executing contracts with the terms of the agreement directly written into code. They build decentralized applications (DApps) that run on blockchain networks. Developers work on improving blockchain scalability, addressing one of the technology's limitations. Some blockchain developers work on developing and improving blockchain protocols. They contribute to the development of consensus algorithms, security mechanisms, and scalability solutions.

Blockchain was created as a public ledger to record all Bitcoin transactions in a transparent, secure, and immutable way. Its primary purpose was to serve as the underlying technology for Bitcoin, a digital currency designed to enable peer-to-peer transactions without the need for intermediaries like banks.

Blockchain Developers: Why are they needed?

Blockchain developers are needed to build secure and efficient financial solutions. They are also needed to create systems that protect sensitive information from breaches and unauthorized access. These days they are also hired to build NFT marketplaces, digital collectibles, and blockchain-based games.

They are hired by a wide range of companies across various industries. Some governments are exploring blockchain for applications like secure voting systems, land registries, and digital identity solutions. Banks, investment firms, and payment processors hire blockchain developers to explore the use of blockchain for cross-border payments, trade finance, and asset tokenization.

Skills required

  • Solidity, Golang, JavaScript
  • Smart Contract Development
  • Truffle, Embark
  • Decentralized Application (DApp) Development
  • Distributed Ledger Technology (DLT)
  • Cryptographic Principles
  • Testing and Debugging

Job titles

  • Smart Contract Developer
  • Blockchain Engineer
  • Solidity Developer
  • Blockchain Architect
  • Blockchain Security Analyst
  • Tokenization Developer
  • Blockchain Project Manager

Blockchain Developer Assessment

The most common assessment framework for Blockchain Developers on HackerEarth includes

A combination of technical evaluations, coding exercises, and behavioral assessments. Here are some common components of the assessment framework:

Code completion tasks

Code completion tasks serve as a practical assessment tool when aiming to hire blockchain developer with good technical skills. By presenting candidates with real-world coding challenges, you can gauge their problem-solving abilities, coding proficiency, and understanding of blockchain concepts. Incorporating code completion tasks into the Blockchain developer hiring assessment process ensures a more accurate evaluation of a candidate's suitability for the role. It aids in making informed decisions when looking to hire blockchain developer who has the right expertise and capabilities.

Multiple-choice questions (MCQs)

A good way to assess a developer's technical knowledge of Blockchain concepts, language features, and best practices is through MCQs. You can choose to include these questions in the Blockchain developer hiring assessment. They can help in evaluating a developer's understanding of fundamentals.

Project-specific questions

You can also include project-specific questions to assess a candidate's knowledge. It can vary depending on your requirements. It will aid you in finding the right candidates with the Blockchain developer skills that the project demands.

Language-specific questions

Blockchain developers can be asked questions related to Decentralization, Smart Contracts, Cryptography, etc. Asking very basic and technical questions can also help assess the candidate’s knowledge and skill sets.

Our bias-free, objective platform has facilitated 1,00,000+ assessments

Steps to Create a Blockchain Developer Assessment on HackerEarth

  1. Log in to Hackerearth assessments
  2. Add questions from our library and create a test
  3. Send invites to candidates
  4. Evaluate our AI-assisted report and shortlist candidates

Assess Blockchain developers for free

Click here now

Sample Questions to Ask a Blockchain Developer

  • Write a Python script to interact with a smart contract deployed on the Ethereum blockchain using the Web3.js library.
  • Implement a function in Solidity to transfer tokens between two Ethereum addresses while deducting a transaction fee.
  • Write a smart contract in Solidity that implements a simple decentralized voting system.
  • Explain how to handle private key storage securely in a blockchain application.
  • Write a Python script to generate a new Bitcoin address using the Bitcoin Core API.

  • Which programming language is commonly used for writing smart contracts on the Ethereum blockchain?
    1. Java
    2. C++
    3. Solidity
    4. Python

  • In a blockchain context, what does UTXO stand for?
    1. Unspent Transaction Output
    2. User Transaction Operation
    3. Universal Token Exchange Order
    4. Unified Transaction Execution Output

  • Which of the following blockchain platforms is designed for private and consortium networks rather than public networks?
    1. Bitcoin
    2. Ethereum
    3. Hyperledger Fabric
    4. Binance Smart Chain

  • How are variables declared in Solidity, and what are the different data types available for variables?
  • Explain the concept of "state variables" and how they differ from "local variables."
  • What is an event and why are events commonly used in smart contracts?
  • What are some common security best practices and considerations when developing smart contracts in Solidity?
  • What are the differences between "memory" and "storage", and when should each be used?

  • Explain the role of private and public keys in blockchain cryptography. How are they generated and used?
  • Why are hash functions essential in blockchain technology?
  • How does a Merkle tree enhance the efficiency and security of blockchain data structures?
  • What is the difference between symmetric and asymmetric cryptography, and when is each used in blockchain applications?
  • How does a distributed ledger utilize consensus algorithms to achieve security and trust among participants?

These sample questions provided here are for interviewing early-experience talents. For more customized assessments for candidates with higher experience, you can contact our team at or request a demo here.

Guidelines for Writing Job Description for Blockchain Developers

Job title

In the Blockchain developer job description, begin with a clear and concise job title that reflects the role, such as "Smart Contract Developer", "Blockchain Engineer”, “Solidity Developer”, “Blockchain Architect”, or “Blockchain Security Analyst". Including a clear title will filter out candidates beforehand. Hence, it can help you find Blockchain developer whose skillset aligns with the role you are hiring for.

Job summary

Provide a brief overview of the position, clarifying the key responsibilities and objectives. Describe what the user's primary focus is and how it contributes to the company's goals. Including a summary in the Blockchain developer job description can provide candidates with an overview of the role they are applying for.


A Blockchain developer job description should outline the specific tasks and responsibilities that the Blockchain developer will be expected to handle. This may include:/p>

  • Developing blockchain protocols, smart contracts, and decentralized applications (DApps)
  • Designing and coding smart contracts that execute on the blockchain
  • Integrating blockchain technology with existing systems and applications
  • Understanding and implementing different consensus algorithms
  • Ensuring the security of the blockchain network

It's an important part of the Blockchain developer job description. These key points will help developers understand the job requirements.

Skills and qualifications

List the essential Blockchain developer skills and qualifications that candidates must possess, including, but not restricted to:

  • Proficiency in blockchain development languages and platforms like Solidity, Ethereum, Hyperledger Fabric, etc.
  • Strong knowledge of blockchain fundamentals and decentralized technologies
  • Smart contract development expertise
  • Cryptography and encryption knowledge
  • Security-conscious mindset for securing blockchain applications

Mentioning the required Blockchain developer skills can help candidates understand the role they are applying for. As a result you can find and hire Blockchain developer with the right skillset.

Preferred skills

Mention any additional Blockchain developer skills or qualifications that would be beneficial but not mandatory for the role. It might attract candidates with broader skillset and thus help you hire Blockchain developer with exceptional skills. You can also ask for experience with specific tools, libraries, or domains.

Education and experience

Specify the educational background and professional experience required for the position. This could range from a bachelor's degree in computer science or a related field to several years of relevant experience. Mentioning these prerequisites can help you filter out the candidates beforehand. And thus help you hire Blockchain developer with the qualifications you are looking for.

Company culture and EVPs

Briefly highlight your company's culture, values, and any unique perks or benefits offered to employees that can help attract candidates who align with your company's ethos.

Application instructions

Provide instructions on how candidates can apply for the position. Include details such as where to send their resume, portfolio, or other required documents. Also, specify the deadline for applications, if applicable. It's another crucial point to be included in the Blockchain developer job description.

Equal Opportunity Statement

Include a statement affirming that your company is an equal opportunity employer committed to diversity and inclusion.

You can incorporate gender-neutral pronouns like 'they/them' to promote an inclusive workplace. Additionally, it's beneficial to align your developer personas with your job profiles before advertising an open position. This approach ensures that your job descriptions resonate with a diverse range of candidates.

Download our guide for writing better developer personas

How to Conduct Blockchain Developer Job Interview

Skill-first hiring requires that the developer interview process be designed to understand the candidate’s skill and experience in the given domain. You can consider the following guidelines when conducting a face-to-face interview with a Blockchain developer:

Conduct a real-time technical assessment

The interviewee would most likely have completed a take-home assessment before the interview. However, using the interview platform to assess skills in real time will tell you a lot about the candidate’s communication skills and thought process - skills that are not evident in an assessment.

FaceCode is HackerEarth’s flagship tech interview platform with a built-in question library you can use to test the candidate’s knowledge of Blockchain and related concepts they claim to be familiar with. The built-in IDE environment can be used for assessing their ability to write clean, efficient, and maintainable code. You can also use the pair-programming method to observe their problem-solving approach, logical thinking, and attention to detail.

Understand the candidate's project experience and review portfolio

During the Blockchain developer interview assessment, ask the candidate about their past or current projects. Find out about their work experience and how they contributed to those projects, focusing on the skills needed for the job. Have them explain a project they did using Blockchain, describing what they did and their responsibilities. You can also look at their portfolio or code samples if they have any to see how they write code, document their work, and how good their projects are.

Understand if they are a good culture and team fit

Another crucial aspect to check during the Blockchain developer interview assessment is if they align with your organization's values. While technical skills are essential for a developer, the significance of cultural fit should not be overlooked. The ideal candidate must possess not only accurate coding abilities but also effective communication and collaboration skills to thrive in agile and collaborative environments. Evaluating a candidate's capability to work both independently and collaboratively in a team is crucial. This assessment provides valuable insights into the candidate's problem-solving skills, communication, and adaptability, helping to determine their fit for the role and the team dynamics.

Additionally, this evaluation offers engineering managers a chance to exhibit their team culture and values, enabling them to find a candidate who aligns well with the team's ethos.

Start free trial

30,000+ recruiters and hiring Managers across 1000+ businesses grow their tech teams with HackerEarth



Look for candidates with proficiency in blockchain development languages such as Solidity, Go, or Rust. Focus on the concepts that are fundamental to blockchain security. For example, the understanding of cryptographic principles, including encryption, digital signatures, and hashing.

Consider candidates with relevant certifications but always give preference to their real life experiences and projects. Look at their portfolio or GitHub repository showcasing their work.

If the job role is focused on a particular blockchain platform or framework then deep expertise in that specific framework is typically more important than familiarity with others. Experienced developers can often transfer their skills from one blockchain framework to another relatively quickly. Look for candidates who demonstrate adaptability and a strong foundation in blockchain fundamentals.

Some projects may involve multiple blockchains or require interoperability between different frameworks. In such cases, having experience in more than one framework can be beneficial.

A blockchain engineer has technical proficiencies such as blockchain development using languages like Solidity. They possess smart contract development expertise, cryptography knowledge, a strong security focus, and a grasp of consensus algorithms and token standards. Additionally, they excel in testing and quality assurance, and continuous learning in the fast-evolving blockchain domain.

To assess a candidate's real-world project-handling skills begin by reviewing their portfolio. In a technical interview, discuss a project and their problem-solving strategies.

Present them with real-world blockchain-related problems or scenarios and ask them to propose solutions. Examine their GitHub activity, including the frequency of contributions, and participation in open-source blockchain projects.

Depending on the organization and project, the required skills may vary. In finance and banking, proficiency in blockchain development, smart contracts, cryptography, and knowledge of financial regulations are crucial. In real estate, expertise in tokenization of real estate assets, and smart contracts for property transactions are required.