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The Art of Hiring Skillful Back-end Developers/



Michael is a software engineer and startup growth expert with 10+ years of software engineering and machine learning experience.

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The Art of Hiring Skillful Back-end Developers

In the app development world, designers and front-end developers often bask in the spotlight for creating visually appealing interfaces. However, the true magic that brings an application to life happens behind the scenes, thanks to the dedicated work of back-end developers.

The back end of an app is a realm where technology and advanced programming seamlessly fuse into a complex and continuous process. While it may seem mysterious to those who don’t fully grasp the inner workings, it’s the back-end specialists who ensure that the under-the-hood components run like a well-oiled machine.

These unseen heroes oversee critical elements such as servers, applications, and databases, working diligently to guarantee that everything on the user interface performs its intended functions. In essence, a back-end developer is the mastermind responsible for constructing and maintaining the technology that makes everything created by front-end developers function flawlessly.

Despite the perceived complexity of back-end development, including challenging programming languages like Java, the demand for these tech wizards is on the rise. The continuous growth in the number of back-end developers underscores their indispensable role in application development.

The Crucial Roles and Responsibilities of Back-End Developers

Back-end developers collaborate closely with front-end developers, full-stack developers, and UX specialists, all driven by the shared mission of creating robust technology solutions for a diverse range of businesses. At the core of a back-end developer’s role lies the responsibility of ensuring that the applications they oversee can withstand heavy traffic loads and operate seamlessly even with resource-intensive scripts.

In addition to this, back-end programmers shoulder the critical tasks of maintaining and continuously testing the existing back-end elements of applications. This meticulous testing guarantees that all components perform swiftly and efficiently, free from interruptions or glitches. Back-end developers also take charge of data storage, demonstrating their prowess in data security and compliance standards.

The typical responsibilities of a back-end developer encompass:

  1. Creation and Maintenance: Developing and sustaining a variety of web applications to keep them running smoothly.
  2. Database Management: Integrating and managing databases, a fundamental element of application functionality.
  3. Cloud Integration: Seamlessly integrating cloud computing solutions to enhance performance and scalability.
  4. API Integration: Expertly incorporating third-party APIs to broaden an application’s capabilities.
  5. Security Vigilance: Safeguarding applications against potential security threats and cyberattacks.
  6. Data Handling: Gathering, generating, and analyzing critical data for informed decision-making.
  7. Optimization: Ensuring top-notch efficiency and speed in applications under their care through high-quality coding practices.
  8. Server Environments: Navigating and optimizing hosting environments to guarantee seamless operation.
  9. Problem-Solving: Swiftly addressing issues, whether it’s troubleshooting, debugging, or resolving technical challenges.

Essential Skills for Back-End Developers

Now that you’ve grasped the essence of back-end development and its associated roles, it’s clear that these responsibilities can be classified into two key areas: hard skills and soft skills. Exceptional back-end developers should possess both of these skill sets to stand out in interviews.

For junior back-end developers, practical experience with at least one back-end framework is crucial. Often, employers hiring entry-level developers seek candidates with a Bachelor’s degree in Computer Science or a related field.

Key Technical Proficiencies for Back-End Developers

An ideal candidate with professional experience should demonstrate most of the following skills:

  • Profound practical knowledge of a scripting language (e.g., PHP, C#, Java, or JavaScript).
  • Competency in using frameworks like Laravel, Flask, Django, Ruby, or Express.
  • Proficiency in working with and configuring databases and managing servers (e.g., SQL, MySQL, and Oracle).
  • Familiarity with version control systems (e.g., Git, SVN, or CVS).
  • Strong understanding of API architectural styles such as SOAP and REST.
  • Expertise in data security and compliance, particularly significant post-GDPR.
  • Basic understanding of common front-end technologies like HTML, CSS, and JavaScript.

Highly Recommended Soft Skills for Back-End Developers

Although soft skills are sometimes underestimated, it’s essential to evaluate whether an applicant possesses the following attributes:

  • Strong problem-solving skills.
  • Keen attention to detail.
  • Excellent analytical abilities and strategic thinking.
  • Effective communication skills.
  • The ability to collaborate as a team player.

Popular and In-Demand Back-End Programming Languages

Back-end programming languages encompass a variety of approaches, including object-oriented scripting languages that connect attributes and methods within objects. Additionally, there are languages that involve compilation rather than interpretation, which can influence factors like loading times, code readability, and processing power required to execute an application.

Now, let’s explore the widely favored programming languages that millions of back-end developers across the globe utilize:

These languages offer versatile solutions for building the robust back-end infrastructure required for today’s software applications.

Certainly, here are two additional lines for each of the mentioned programming languages:


Python is known for its simplicity and readability, making it a top choice for web development and data science projects. Its rich library ecosystem accelerates development.


Java’s platform independence and strong community support make it a go-to language for large-scale applications, especially in the enterprise realm.


Ruby’s elegant syntax and Rails framework facilitate rapid development, making it a favorite for startups and web applications.


PHP powers a significant portion of the web, offering ease of use and integration with popular databases like MySQL.

Node.js (JavaScript)

Node.js’s event-driven architecture and JavaScript familiarity enable high-performance server-side applications.


C# is vital for Windows-based applications, and it excels in creating desktop software and game development.

Golang (Go)

Go’s efficiency, simplicity, and built-in concurrency support suit applications demanding speed and efficiency.


Rust’s focus on memory safety and performance is ideal for systems programming and building secure applications.


Kotlin is praised for its seamless Android app development and modern language features that enhance productivity.


Scala combines object-oriented and functional programming, making it a solid choice for scalable and maintainable code in the enterprise domain.

How to interview a Back-End developer

When interviewing Back-End developers, it’s essential to tailor your questions to their experience level, whether they are Junior, Middle, or Senior developers. To assist you in this process, we’ve provided three questions and suggested responses for each level:

Interviewing Junior Back-End Developers

Q1: Explain SQL injection.

A1: SQL injection occurs when external input isn’t properly segregated from internal code, allowing attackers to insert malicious SQL statements into an application. This is a common type of injection attack.

Q2: Define application cache, its storage, and use.

A2: Application cache stores temporary data for quick access. It often resides in separate databases like Redis or Memcached, enabling rapid read and write operations. Caching minimizes heavy queries to the main application database, improving overall performance.

Q3: How do you identify slow queries in MySQL?

A3: To find slow queries in MySQL, you can enable a log file for slow queries and set a time threshold to determine slowness. Cloud environments like Amazon RDS Performance Insights offer additional tools for locating slow or long-running queries.

Interviewing Middle Back-End Developers

Q1: Analyze this SQL query: SELECT FROM table WHERE field = null. What will it return and why?

A1: This query will return an empty set, even if the table contains records with null values in the specified field. Comparison operators like =, <, or <> cannot test for NULL values. To select records with null values, the IS NULL operator must be used.

Q2: Explain the main advantages of microservices.

A2: Microservices offer advantages such as interoperability, loose coupling, and reusability. They are accessible through various networks, use standard protocols like HTTP and SOAP, and transfer data in XML or JSON. This architecture allows development in multiple programming languages, enhancing flexibility and reducing dependencies.

Q3: Describe RESTful API design constraints.

A3: RESTful APIs adhere to design constraints, including a uniform interface, client-server separation, stateless operations, resource caching, a layered system, and optional code-on-demand. These principles ensure clear resource identification, client-server distinctions, and stateless communication, enhancing system performance.

Interviewing senior Back-End developers

Interviewing Senior Back-End developers demands in-depth and nuanced questions to assess their expertise. Here are three questions and suggested responses for your interview:

Q1: Explain the API Gateway pattern.

A1: The API Gateway is a central server serving as the exclusive entry point to a system. Similar to the Facade pattern in object-oriented design, it encapsulates the internal system architecture. The API Gateway provides a customized API for each client’s specific needs and can perform additional functions like load balancing, handling static responses, authentication, and request management. This approach simplifies client interactions by allowing them to send requests to the API Gateway rather than invoking specific services directly.

Q2: How do you achieve High Availability (HA)?

A2: High Availability ensures uninterrupted access to an application’s system. It is measured by uptime percentages, ranging from 99% (3.65 days per year) to 99.999% (5.26 minutes per year). Achieving HA involves multiple factors:

  • Infrastructure redundancy with a high number of nodes and cluster usage.
  • Comprehensive backups and recovery plans for software and hardware.
  • High-quality codebase and multi-step CI/CD pipelines to eliminate critical software issues.
  • Utilizing multiple caching layers and advanced load balancing for handling unexpected traffic.
  • Leveraging advanced programming architectures, including extensive use of microservices and layering.
  • Real-life examples of using these techniques to enhance availability are a valuable addition to the response.

Q3: Define a Distributed Transaction and its operation.

A3: A distributed transaction involves performing a set of operations on data across multiple data repositories, often distributed across separate nodes connected through a network or multiple databases on a single server. To execute a distributed transaction, a transaction manager is required to coordinate resources. This manager can be one of the data repositories involved in the transaction or an independent resource responsible solely for coordination. The transaction manager determines the success or failure of a transaction and commits or rolls it back accordingly. In case of failure in any part of the transaction, such as an unavailable network resource, a rollback is triggered, ensuring no net changes across other network resources.

Incorporating Coding Challenges:

Conducting coding challenges as part of the interview process is essential. It provides candidates with real-life scenarios, allowing you to evaluate their ability to write clear, practical code. This approach ensures that candidates possess the necessary skills and expertise to contribute effectively to your project.

Are Back-End developers expensive to hire

Back-end developer salaries can vary significantly based on factors like programming language expertise, seniority, and task complexity. The developer’s experience is a crucial factor influencing their rate:

  • Junior Back-End developers typically earn between 41-100 USD/hour.
  • Mid-level Back-End specialists may command rates ranging from 61-120 USD/hour.
  • Senior Back-End developers, with extensive experience, can earn rates between 81-160 USD/hour.

Here are the average annual salaries for Back-End developers based on experience and region, according to Payscale:

  • Junior Back-End Developer: Annual salaries vary by region but often fall in the lower to mid-range of the overall developer pay scale.
  • Mid-Level Back-End Developer: These developers with a few years of experience generally command higher salaries, especially in regions with a strong tech industry.
  • Senior Back-End Developer: With substantial experience, these developers often earn top-tier salaries, especially in tech hubs and regions with a higher cost of living.

However, to hire the Best Backend Developers in the world while also not breaking the bank visit: https://slashdev.io .  At slashdev.io you can find proficient backend developers ranging from 28-38 USD per hour.


Hiring a skilled back-end developer is crucial for project success, but it’s important not to let the search process drag on endlessly. While expertise is vital, consider compatibility and teamwork. Sometimes, highly professional candidates may not fit your culture or collaborate effectively. Junior developers can bring fresh perspectives and grow with your company. The hiring process involves assessing technical skills, cultural fit, and long-term potential. Taking a chance on someone knowledgeable and friendly can lead to success, ensuring you find the right developer for your project.