Context Considering the rising popularity of Node.js and the fact that a very largepercentage of websites today are based on PHP, there is a need to understand thesimilarities and differences between these languages.  Comparing their most popularserver-side  frameworks  is  valuable  to  developers  in  seeing  the  advantages  of  usingone over the other - for both user and developer. Objectives In this study we investigate how Express.js and Symfony compareagainst each other in terms of installation, functionality and performance. Thiswill provide understanding of when to use JavaScript frameworks and when to usePHP frameworks for server-side projects. Method A literature study was done to answer what similarities and differences existbetween the frameworks. To explore how they compare in performance when mul-tiple users are actively sending requests to the server, an experiment was performed.Another experiment was carried out to measure performance in CPU-intensive ap-plications. Results The result shows that both frameworks are quick to install and it is a fastprocess to setup a basic application. Both frameworks are highly cuztomizable andconfigurable because they are supported by a big open source community and theonly difference is that Express is supportive of single-page applications which Sym-fony can not do on its own. Express was better than Symfony to handle multipleconcurrent users when it comes to CPU usage and time it takes for the requests. For100 and 1000 requests, Express CPU usage varied more than Symfony, but at 10000and 100000 it varied less. In all tests with concurrent users, Express was faster. Testsperformed in the second experiment showed that Symfony is only able to use 1 corewhen making the requests while Express is able to use multiple cores. Even thoughSymfony was limited by 1 core it was faster, most likely because it used more memory. Conclusions This study shows that there are more similarities than differencesbetween Express and Symfony. They both strive for high customization and highflexibility with a goal to make tedious tasks easier for the developer. Both rely onopen source modules and components to add additional functionality. Out of thebox, Express comes with less functionality as it strives to be minimalistic. However,to install Symfony is slightly quicker than Express and requires no code. Thereare currently more daily downloads of Express than Symfony, and therefore it’sconsidered more popular. It’s supportive of JavaScript-only for front- and back-endand is able to handle more concurrent users than Symfony, and is therefore betterfor high-traffic websites. But Symfony is able to handle CPU-intensive applicationsbetter than Express, and is able to load in large data sets faster, making it a goodchoice for applications with a lot of data and high CPU usage.

APIs can have different architectures and standards, one of which is REST. REST stands for representational state transfer and is a commonly used architecture when implementing and creating APIs for the web. Choosing a web framework for a REST API implementation is not as trivial as one might think; there are many metrics to consider, one of which is performance. In this study, we compared the most used back-end web frameworks in 2021, ASP.NET Core, Express.js, and Flask, to see which performs best in throughput, response time, and computer resource usage. Finding the best-performing framework will help future developers choose which framework to use in terms of performance. Selecting a good framework from the beginning is essential to prevent the need to change framework in the future. To benchmark the different APIs, we did an experiment where we used JMeter, an open-source software for testing the performance of websites and APIs. By varying the number of virtual users and throughput, we were able to find the limit of each framework and their respective resource usage during different loads. We have concluded that ASP.NET Core had the best performance when it comes to response time and throughput. Furthermore, ASP.NET Core had the most efficient memory utilization throughout the entire experiment, and during loads higher than 4500 throughputs per second, it was also the most CPU efficient. Below 4500 throughput per second, Express.js was the most CPU-efficient framework but still had more memory usage than ASP.NET Core. According to our metrics, the performance of Flask was far behind Express.js and ASP.NET Core and should therefore not be considered a high-performance framework.

The aim of the master thesis is to provide visitors of various types of objects - typically galleries, museums, etc. with additional information about exhibited objects with emphasis on visual display in augmented reality. It includes an analysis of already existing solutions, design and implementation of the entire system needed for deployment. From the point of view of the content creator (administrator), the system represents a complex solution enabling the creation of an interactive walk - scanning 3D objects, scanning 2D objects and adding content to the given objects. On the other hand, the tool for visitors (users) who are part of an interactive walk, provides additional information about objects primarily located near the user, which are automatically detected by the camera on the mobile phone. Solution includes augmented reality, which is implemented using ARKit technology, so the final application is built on the iOS platform. The work addresses the issue of detection of 3D objects and their subsequent recognition, along with the way to work with this information, how to store it and then use it for purposes of this thesis. In the final solution, emphasis is placed on the simplicity of the usage (guide marks, hints...) and overall user experience.

Modern web applications are growing in complexity and becoming more widely used. Using frameworks to build APIs is a popular way for both hobby developers and businesses to speed up development time and save costs. With this dependence on frameworks to be the foundation for potentially large applications comes the need to understand their performance qualities and which areas they are best suited for. This study compares the performance of the two similarly popular frameworks ASP.NET Core and Express.js, when used together with a MySQL Database to build Web APIs. This was done by building two different API implementations in each framework, one employing a RESTful approach and the other using the new querying language GraphQL. Experiments were run where the peak CPU usage, peak memory usage and response times were measured.The results of the experiments were that in a RESTful API, ASP.NET Core is faster at serving requests during lower loads whereas Express.js outperforms ASP.NET Core when faced with a higher amount of concurrent requests that fetch a lot of data. In a GraphQL API Express.js was able to perform similarly or better in all cases in terms of response times and resource usage compared to ASP.NET Core.