Complete hiring guide for Symfony developers

A hiring process is not supposed to be a breeze, but it can be made easier with a few helpful tips and tricks. Of course, you cannot do this alone, and you need directions, guidelines, suggestions, and external assistance from recruiters and talent acquisition specialists.

Even with substantial expertise and knowledge of a specific technology, it doesn’t hurt to tick all the boxes to shorten the timely and costly hiring process and meet the business requirements you need. It takes time to create a job ad, look for talent in all the right places, carefully conduct the selection of candidates, and schedule and organize interviews.

The hiring process has to be done carefully. Otherwise, all the efforts and resources seem lost and irretrievable. Hence, you need to consider all factors encompassed in evaluating the candidates—background, expertise, education, experience, good interview questions, technical test result, and similar.

Whether you need just one dev or to form a development team, we covered all of these relevant factors below, providing answers to common hiring dilemmas. We mention valuable technology stats, benefits of this technology, possible challenges and how to deal with them, and what to focus on during the assessment process.

About Symfony

Symfony is a PHP framework, a stable development environment of an open-source type, used for creating web applications and websites. This framework is an asset for the developer’s work because it tailors to specific application development needs through custom additions of modules.

Symfony has an MVC architecture (model-view-controller) and helps to create web apps and websites in a layered, well-structured, and logical way in no time. It allows easy and fast software division into small parts and easy deployment and maintenance.

Coding and web development become simple, easy, yet high performance, combining the MVC architecture with PHP as the programming language basis.

Useful stats

There have been several releases and versions of Symfony, with the 2.0 first released in 2011 and the latest version 6.12, released in May 2022.

Despite its simplicity and functionality, Symfony is relatively widespread, with 4.25% of devs stating they prefer it to all frameworks. Still, these stats rank lower regarding preferences, and 47.59% of devs like working with it, whereas 52.41% do not choose it primarily.

Regarding the salary of a Symfony developer, the annual average is $97,587, with the lowest and highest being $37,500 and $142,000, respectively.

Popular brand names that rely on Symfony usage

1. Vogue France & Vogue Netherland
2. Spotify
3. NatGeo Play France
4. National Geographic Travel
5. BlablaCar
6. Trivago
7. Course Hero
8. Doc planner
9. Dailymotion
10. Swiss Open Government Data
11. eRepublik

Interviewing a Symfony developer

Helpful tips for a pre-screening interview

External help in hiring a Symfony developer is always beneficial because talent acquisition specialists know how to go into detail for the initial screening and interview stages during the dev hiring process.

The recruiters mainly focus on checking all the applications and candidates’ profiles, whether the candidate is an excellent cultural fit or similar. The point is not just for recruiters to find someone that fits the regular mold—where every resume requirement box is ticked off nicely for the job. There is always more to look for beyond just technical skills and descriptions of work experiences.

Besides the technical skills, there are also non-technical skills to check for a complete evaluation of the candidate. All of this combined creates the full, complete representation of the candidate, so you can easier decide later on why they’ll be a good fit or not.

Technical skills of a Symfony developer

An excellent Symfony developer would ideally have substantial knowledge and experience with the following:

• Symfony—Working with Symfony is an essential requirement for the dev that wants to build apps quickly and efficiently.
• PHP—Since Symfony contains sets of PHP components, it is crucial to master working with PHP.
• TDD (Test-Driven Development)—With TDD, there are fewer bugs, leading to an excellent quality code. For producing a clean code, TDD is vital to use.
• OOP (Object Oriented Programming) makes code maintenance and modifications easy. The dev can create new objects over existing objects with little to no changes.
• Git and version control—Git and other version controls benefit a project's efficiency and speed, resulting in easier code tracking and managing, and overall provides fast and feature-rich performance.
• MySQL—For easier management of database systems, the dev needs to work with MySQL, which is also helpful for data warehousing and logging applications.

Non-technical skills of a Symfony developer

The non-technical skills of a developer are just as essential as the technical ones because these skills tell you more about the personality and professionalism of the candidate you’ll potentially hire, not just their expertise.

The first essential things that a recruiter or talent acquisition specialist checks are English language proficiency, punctuality, and presentability. If the dev has good or excellent English language usage, it means fewer linguistic barriers during the communication with clients. If the dev shows up on time or a bit earlier for the interview, they respect the recruiter’s time and show they are responsible and reliable. At the same time, presentability is also vital and shows the interviewee's professionalism.

Apart from these three aspects, it is good to also focus on the developer's overall attitude and listening skills. Are they listening carefully to what is asked of them? Is there interrupting, or are they focusing on the conversation? Is the dev improvising with answers, or do they ask for clarification to questions they do not understand fully? Communicativeness and openness are also crucial, complementing the professional attitude and communication skills mentioned above.

Symfony interview questions

You or the talent acquisition specialist can consider the following interview questions, besides many others, you can use:

1. Explain the correlation between Symfony and Laravel

Expected answer: The primary connection between the two is in the database interaction. Laravel uses Eloquent (object-relational mapper - ORM) as its independent library, whereas Symfony uses Doctrine (a third-party project) for database interaction. These two have quite a few things in common, but initially, Laravel uses many components of Symfony or around 30% of it.

2. What is Symfony Controller?

Expected answer: A Symfony controller represents a class method for requests’ accepting and returning a Response object. The controller is accessible and viewed when mapped with the URL beforehand. Simply put, Symfony controller is a PHP function that retrieves HTTP request information and turns them into an HTTP response that could vary and show as XML format, 404 error, redirect, or HTML page, among others.

3. What are Symfony annotations?

Expected answer: The annotations are used for information mapping and configuration validating. We can do this with YAML, XML, and PHP as well, and the benefit of using annotations is easier to define within one file. For better annotations support, there are the bundles JMSSecurityExtraBundle and SensioFrameworkExtraBundle too.

4. Are there server requirements for Symfony installation? If so, what are they?

Expected answer: For Symfony installation, make sure you have PHP 7.1 or higher. Also, you need to install Composer too.

5. What are Symfony Bundles?

Expected answer: The bundles in Symfony are collections that are organized in a certain way and structure. Usually, they are collected files and folders that are reused for many applications.

6. Which directory stores Symfony logs?

Expected answer: You can find the stored Symfony logs in the myproject/log/directory. This is incredibly simple because one file is appointed per environment and application.

7. What are Symfony form helper functions?

Expected answer: The Symfony form helper functions are helper functions you can create for taking and returning templates, entities, services, routes, forms, translations, or events. With the help of Symfony Plugin and its return type inference, plus the parameter types, you can create the helper functions easily, as mentioned above.

8. What is a Symfony default port, or how is it named?

Expected answer: A default port is a web server port as a logical endpoint of connection with a network. The Symfony default port is 8000.

9. How do you get the Symfony current route?

Expected answer: For getting the Symfony current route, you need to use the method $request->get(‘_route’);

10. What is a FlashBag?

Expected answer: FlashBag in Symfony is used for holding data when the dev is making page redirecting.

Essentials and assessment of a Symfony developer

To summarize, the following skills and technologies are the essentials that you need to notice when you assess the dev:

A minimum of 2+ years of experience with PHP and Symfony Knowledge of TDD (Test-Driven Development) and OOP (Object Oriented Programming) Experience with HTML, CSS, Bootstrap Experience with Git and similar version controls Knowledge and experience with database management systems like MySQL.

We also asked Ben Kachoud Hicham, a full-stack developer at Proxify, to tell us more about the essentials of a Symfony developer:

“A great Symfony dev needs to be adaptable to changes and frequently follow what is new in the developers' community. They should understand the Symfony components, emphasizing Security and Form, among others. The Symfony dev should also have good experience with the design patterns, OOP, and SOLID principles. They also need to master the Symfony framework best practices too, and focus on reading the official documentation in-depth.”

Ben Kachoud Hicham

What distinguishes a great Symfony developer from a good one?

A good and a great developer have many things in common, but you can still easily distinguish who’s the better one of the two.

A great Symfony developer will foremost have more years of experience working with this framework. The number of years is not relevant by itself only, but also it matters if the dev used Symfony predominantly in all those years of development experience.

Another clear sign of an excellent Symfony dev is if they aced their technical, coding tests, and interview stages. With more in-depth answers, cleaner codes, and overall better interview performance in all phases, it’s evident that they are a better Symfony developer out of many applicants.

Also, you might notice during the interviewing whether the dev obliges and answers questions without much forethought or elaborations or not. A great dev would always give a bit more than asked for because they use critical thinking and think ahead to come to solutions for tasks. When a dev shares their opinion, rest assured that in the future, they will also point out better solutions to something and be proactive too.

From the perspective of Ben:

“A great Symfony developer will know more about this framework and answer every question they are asked. Of course, they need to be more than just Advanced, and the title Expert is something to focus on more. Also, they will know all about the framework’s components in detail.”

Possible challenges during the hiring of a Symfony developer

It is normal to expect some challenges along the search and hiring of a Symfony developer, but if you know the possible challenges, you can surely avoid setbacks at this stage.

One challenge might be the time limitation and budget constraints. Make sure your budget is enough for the whole process, including hiring recruiters, managers, and developers. And, make sure you don’t rush too much, so set a reasonable timeframe for the whole hiring process. A challenge within this challenge are competitors who might even be ready to offer more to the most skilled dev that everybody needs for their company.

Another thing to remember is the demand for Symfony and the demand for Symfony devs. The rarer the best devs for this framework are, the higher the salary. Similar to the point above, be ready to offer more to the best Symfony devs, and win over the competitor that seeks precisely the same dev as you do.

A minor challenge is also perhaps the time zone where the dev is from. This can quickly be resolved, depending on the type of employment or working hours you both agree upon.

Another possible challenge is improperly structured, planned, and conducted recruiting and interviewing. What if there is a golden opportunity for you to get the best Symfony dev, but due to a lack of expertise in recruiters, you miss out on this chance? Ensure you have top-notch tech recruiters and talent acquisition specialists who will do their best to find the best in the talent pool.

Why and when do you need to hire a Symfony developer?

Since you are interested in the hiring process of a Symfony dev, you assume why you need to include this framework in your business overall, but let’s go over the upsides of hiring a Symfony dev and when this is the best thing to do.

When the project you work on needs the creation of quite large web apps, Symfony comes in handy and simplifies the work the dev does; it saves time and resources. How? Well, this framework is incredibly fast, even on various hosting solutions. Also, it handles a large system excellently, even those with over a thousand users.

It is also very flexible and adaptable, so if you regularly start projects of various kinds and you cannot pinpoint precisely what the next project will be, rest assured that Symfony can fit in well with most web programs, sites, networks, CMSs (Content Management Systems) and more.

Benefits of Symfony

The benefits of Symfony are:

• Saving time—The development process is shorter and simpler because Symfony accelerates time-to-market with its numerous features.
• Optimizing performance—Symfony consumes less memory and has built-in features that speed up the performance.
• Simple and easy to use—This framework is incredibly simple for the devs, even ideal for beginners. Many best practices are embedded, such as guidelines and tutorials, detailed, informative documentation, and guiding examples. Also, there are numerous command tools for easy project management.
• Customizable—When a dev uses Symfony, they can make quite a few adjustments and customize things as needed. For example, ‘micro framework’ for particular functionalities, ‘brick-by-brick’ for parts of the framework and selective, limited functions, and ‘full-stack’ for complex products and more functionalities at once.
• Simplifies testing—The unit testing gets easier and automated with the help of the PHPUnit Independent Library.
• Practical toolbar—The toolbar of Symfony simplifies the debugging the dev does, with substantial information and clear guidelines displayed.
• Popular and in demand—Big brand names like to use Symfony in their work and websites, proving this is an excellent framework for demanding and large-volume projects with complex information and components.
• Convenient—Since Symfony is a practical and high-end framework, it makes the development process comfortable and as easy as possible. The proof of this is the customer-centric product development and the tools for easy code corrections and solving any issues regarding security.
• Easy deployment—Devs will save time with the automated processes this framework offers, with a configuration per each activity, separately.
• Extensive community and quality support—With a large community of users, getting the proper help and directions is easy. The dev can get tips on various methods and tools, updates, and all from experts with over a decade of experience.

Here, Ben added:

“Among the many benefits of using Symfony is the large community that continuously works on improving this framework and sharing useful information. Besides, with this framework, the dev can use features they need and don’t need to depend on using all of them at once. Plus, the OOP is another major benefit for the work overall. Companies benefit greatly when the developers use Symfony—it’s amazing how full projects and microservices can be easily finished in no time.”