Deep Dive Into Backend Engineering

13 min readJul 12, 2023

Backend engineering is the process of designing, building, and maintaining the server-side of a software application. Backend engineers are responsible for the logic that powers the application, as well as the data that is stored and accessed by the application. They typically work with a variety of technologies, including programming languages, databases, and web frameworks. They must have a strong understanding of software architecture and design principles, as well as the ability to troubleshoot and debug complex code.

Backend engineers play a vital role in the development of software applications. They are responsible for ensuring that the application is reliable, scalable, and secure. They also work closely with front-end engineers to ensure that the application is user-friendly and meets the needs of the end users. Lets explore some essential skills that a backend engineer should have beyond coding that makes them stand out.

Communication Protocols

In backend engineering, communication protocols are used to facilitate communication between the frontend and backend of a web or mobile application, as well as between different backend services.

Some of the most common communication protocols used in backend engineering include:

HTTP: The Hypertext Transfer Protocol (HTTP) is the most widely used communication protocol on the internet. It is used to transfer data between clients (such as web browsers) and servers. HTTP is a request-response protocol, which means that the client sends a request to the server, and the server sends a response back to the client.
HTTPS: HTTPS is a secure version of HTTP that uses Transport Layer Security (TLS) to encrypt data between the client and server. This makes HTTPS more secure than HTTP, and it is often used for websites that handle sensitive data, such as credit card numbers or passwords.
WebSockets: WebSockets are a newer communication protocol that allows for bi-directional communication between the client and server. This means that the client and server can send messages to each other at any time, without having to establish a new connection for each message. WebSockets are often used for real-time applications, such as chat apps or multiplayer games.
gRPC: gRPC is a high-performance, open-source RPC framework that uses HTTP/2 as its transport layer. gRPC is often used for microservices architectures, as it allows for efficient communication between services.
AMQP: The Advanced Message Queuing Protocol (AMQP) is a messaging protocol that is used to exchange messages between different applications. AMQP is a reliable protocol, and it can be used to send messages over a variety of networks, including the internet.

In addition, understanding TCP, UDP and networks in general is an added advantage. The choice of communication protocol depends on the specific requirements of the application.

Web Servers

Web servers are an essential part of backend engineering. They are responsible for receiving requests from clients, such as web browsers, and returning responses. The responses can be static content, such as HTML pages or images, or dynamic content, such as the results of a database query. They are responsible for:

Serving static content: Web servers are responsible for serving static content, such as HTML pages, images, and CSS files. This content is typically stored on the web server’s hard drive and is served to clients when they request it.
Processing dynamic content: They can also process dynamic content. This content is generated on the fly by the web server, typically in response to a request from a client. For example, a web server might generate a dynamic web page that includes the results of a database query.
Managing sessions: Web servers can also manage sessions. A session is a way to track a user’s activity on a website. This is typically done by assigning the user a unique identifier, which is stored on the web server. The web server can then use this identifier to track the user’s activity throughout the website.
Managing security: Web servers can also manage security. This includes tasks such as authenticating users, encrypting data, and preventing unauthorized access to the website.
Caching: Can cache static content, which can improve the performance of a website.
Load balancing: They can be used to load balance a website, which means that they can distribute traffic across multiple servers. This can help to improve the performance of a website, especially during periods of high traffic.
Content delivery networks (CDNs): Web servers can be used to create content delivery networks (CDNs). CDNs are a way to deliver static content from multiple servers located around the world. This can help to improve the performance of a website for users who are located in different parts of the world.

Proxies

Proxies are an important part of backend engineering. They can be used to improve the performance, security, and scalability of web applications.

There are two main types of proxies: forward proxies and reverse proxies.

Forward proxies sit between the client and the server. They can be used to filter requests, log requests, or sometimes transform requests (by adding/removing headers, encrypting/decrypting, or compression).
Reverse proxies sit in front of a group of servers. They receive requests from clients and then forward them to the appropriate server. Reverse proxies can be used to improve performance, security, and scalability.

Here are some of the benefits of using proxies in backend engineering:

Performance: Proxies can improve the performance of web applications by caching frequently accessed content. This can reduce the number of requests that need to be made to the origin server, which can improve performance.
Security: Proxies can improve the security of web applications by filtering requests and blocking malicious traffic. This can help to protect web applications from attacks such as cross-site scripting (XSS) and SQL injection.
Scalability: Proxies can help to scale web applications by distributing traffic across multiple servers. This can help to improve performance during periods of high traffic.
Bypass geo-restrictions: They can be used to bypass geo-restrictions, which are restrictions that prevent users from accessing certain websites or content based on their location.
Protect user privacy: Proxies can be used to protect user privacy by hiding the user’s real IP address. This can be useful for users who want to protect their privacy while browsing the web.

By understanding the benefits of using proxies, backend engineers can build more reliable and efficient web applications.

Databases

They are used to store and retrieve data, which is essential for most web applications.

There are two main types of databases: relational databases and NoSQL databases.

Relational databases are the most common type of database. They store data in tables, which are made up of rows and columns. Each row represents a record, and each column represents a piece of data about that record. Examples are: MySQL, PostgreSQL, Oracle, SQL Server.
NoSQL databases are a newer type of database that are designed to store and retrieve unstructured or semi-structured data. NoSQL databases do not use tables, and they are more flexible than relational databases. Examples are: MongoDB, Cassandra, DynamoDB, Redis

Backend engineers need to understand the different types of databases and how to use them. They also need to understand the different database queries that can be used to retrieve data from databases.

Databases are used by backend engineering for the following purposes:

Data storage: Databases are a great way to store large amounts of data. They are also very efficient at retrieving data, which can improve the performance of web applications.
Data security: Databases can be used to secure data. This is because databases can be encrypted, and they can also be used to control who has access to data.
Data scalability: They can be scaled to meet the needs of a growing web application. This is because databases can be distributed across multiple servers.
Perform analytics: Can be used to perform analytics on data. This can be used to gain insights into user behavior, which can help to improve the user experience of a web application.
Automate tasks: They can be used to automate tasks. This can be used to improve the efficiency of a web application.

Caching

Caching is a technique that stores frequently accessed data in a temporary location so that it can be accessed more quickly and easily. This can improve the performance of web applications by reducing the number of times that the database needs to be accessed.

There are two main types of caching:

In-memory caching stores data in the memory of the server. This is the fastest type of caching, but it is also the most volatile. If the server restarts, the in-memory cache will be lost.
Disk caching stores data on the disk of the server. This is slower than in-memory caching, but it is more persistent. If the server restarts, the disk cache will be restored.

Backend engineers need to understand the different types of caching and how to use them. They also need to understand the trade-offs between performance and persistence.

Here are some of the benefits of using caching in backend engineering:

Performance: Caching can improve the performance of web applications by reducing the number of times that the database needs to be accessed. This can improve the response time of web applications, which can improve the user experience.
Scalability: Caching can help to scale web applications by reducing the load on the database. This can help to improve the performance of web applications during periods of high traffic.
Cost: Can help to reduce the cost of web applications by reducing the number of database queries that need to be made.
Improve reliability: Can help to improve the reliability of web applications by reducing the number of times that the database needs to be accessed. This can help to prevent the database from becoming overloaded, which can lead to errors.
Improve security: Caching can help to improve the security of web applications by reducing the number of times that sensitive data needs to be accessed. This can help to protect sensitive data from being leaked.

Here are some of the most popular caching solutions used in backend engineering:

Redis: Redis is an in-memory data store that is often used for caching. It is a fast and scalable solution that is well-suited for caching frequently accessed data.
Memcached: Memcached is another in-memory data store that is often used for caching. It is a simpler and less feature-rich solution than Redis, but it is also faster.
Ehcache: Ehcache is a Java-based caching solution that is often used for caching in web applications. It is a reliable and scalable solution that is well-suited for caching frequently accessed data.

Messaging Systems

Messaging Systems are used to decouple different parts of an application, to ensure reliable communication, and to scale applications. There are two main types of messaging systems:

Message queues are a way of storing messages until they are ready to be processed. Messages are stored in a queue, and they are processed in the order in which they are received.
Event buses are a way of publishing and subscribing to events. Events are messages that are published by one part of an application and that can be subscribed to by other parts of the application.

Here are some of the benefits of using messaging systems in backend engineering:

Decoupling: Messaging systems can be used to decouple different parts of an application. This means that the different parts of the application can communicate with each other without having to know about each other. This can make applications more reliable and scalable.
Reliable communication: They can be used to ensure reliable communication. This means that messages are not lost or corrupted, and they are delivered in the order in which they are sent.
Scalability: Can be scaled to meet the needs of a growing application. This is because messaging systems can be distributed across multiple servers.
Implement asynchronous communication: Can be used to implement asynchronous communication. This means that messages can be sent without blocking the sender. This can improve the performance of applications.
Implement event-driven architectures: Can be used to implement event-driven architectures. This means that applications can react to events that occur in other parts of the application. This can make applications more responsive.

Here are some of the most popular messaging systems used in backend engineering:

Apache Kafka: Apache Kafka is a popular message queue that is often used for streaming data. It is a reliable and scalable solution that is well-suited for high-volume data processing.
RabbitMQ: RabbitMQ is another popular message queue that is often used for asynchronous communication. It is a reliable and scalable solution that is well-suited for decoupling applications.
Amazon SQS: Amazon SQSis a managed message queue service that is offered by Amazon Web Services (AWS). It is a reliable and scalable solution that is well-suited for large-scale applications.

API Web Frameworks

API web frameworks are a type of software framework that is used to create and maintain APIs. APIs are a way for different applications to communicate with each other. Some of the most popular API web frameworks include:

Django REST Framework: Django REST Framework is a popular Python framework for creating RESTful APIs. It is a well-documented and well-supported framework that is easy to learn and use.

Express: Express is a popular JavaScript framework for creating APIs. It is a lightweight framework that is easy to learn and use.
Laravel: Laravel is a popular PHP framework for creating APIs. It is a feature-rich framework that is easy to learn and use.
Flask: Flask is a popular Python framework for creating APIs. It is a microframework that is easy to learn and use.
Spring Boot: Spring Boot is a popular Java framework for creating APIs. It is a feature-rich framework that is easy to learn and use.

In addition to the frameworks mentioned above, there are many other API web frameworks available. The best framework for a particular project will depend on the specific requirements of the project.

Here are some of the factors to consider when choosing an API web framework:

Programming language: The framework should be written in a programming language that the developer is familiar with.
Features: The framework should have the features that the project requires.
Documentation: The framework should have good documentation that the developer can refer to.
Community: The framework should have a strong community that can provide support and help with troubleshooting.

Message Formats

Message formats are a way of representing data that is being sent between different parts of a backend application. Some of the most popular message formats include:

JSON: JSON is a lightweight text-based format that is easy to read and write. It is a good choice for messages that need to be human-readable.
XML: XML is a more complex format than JSON, but it is more flexible. It is a good choice for messages that need to be machine-readable.
Protocol buffers: Protocol buffers are a binary format that is very efficient. They are a good choice for messages that need to be transferred over a network.
Avro: Avro is a binary format that is similar to protocol buffers. It is a good choice for messages that need to be transferred over a network.

Here are some of the factors to consider when choosing a message format:

Readability: The format should be easy to read and understand by humans.
Flexibility: The format should be flexible enough to represent the data that the application needs to transfer.
Efficiency: The format should be efficient in terms of space and bandwidth.
Ease of use: The format should be easy to use by the application.

Security

Backend engineers need to understand the different security risks that can affect web applications and how to mitigate those risks.

Some of the most common security risks that affect web applications include:

Injection attacks: Injection attacks are a type of attack where malicious code is injected into a web application. This can be done through the URL, the request body, or the headers.
Cross-site scripting (XSS) attacks: XSS attacks are a type of attack where malicious code is injected into a web application. This code can then be executed by the victim’s browser, which can steal cookies or other sensitive information.
SQL injection attacks: SQL injection attacks are a type of attack where malicious code is injected into a web application. This code can then be executed by the database, which can steal data or even crash the database.
Man-in-the-middle attacks: Man-in-the-middle attacks are a type of attack where an attacker intercepts traffic between a client and a server. This allows the attacker to see and modify the traffic, which can be used to steal data or perform other malicious activities.

Backend engineers can mitigate these risks by following security best practices. Some of the most important security best practices include:

Using strong passwords: Backend engineers should use strong passwords for all accounts, including their web application accounts. Strong passwords should be at least 12 characters long and should contain a mix of uppercase and lowercase letters, numbers, and symbols.
Encrypting data: Backend engineers should encrypt sensitive data, such as passwords and credit card numbers. This will make it more difficult for attackers to steal the data if they are able to gain access to the web application.
Validating input: Backend engineers should validate all input that is received from the client. This will help to prevent injection attacks.
Using a web application firewall (WAF): A WAF is a security appliance that can help to protect web applications from a variety of attacks. WAFs can be used to block malicious traffic, filter out spam, and detect and prevent injection attacks.
Keeping software up to date: Backend engineers should keep all software up to date, including the operating system, web application framework, and any third-party libraries. This will help to ensure that the software is patched against known vulnerabilities.
Monitoring web applications: Backend engineers should monitor their web applications for suspicious activity. This can be done by using a WAF or by setting up alerts for certain types of events.
Backing up data: Backend engineers should regularly back up their data. This will help to protect the data in case of a security breach.

By following these security considerations, backend engineers can help to keep their web applications secure.

Conclusion

Backend engineering encompasses a wide range of skills and knowledge areas. Expand your expertise, stay updated, and continuously learn to thrive in this exciting field.