arXiv subjects

Tomas Cerny

Publications and source records attributed to Tomas Cerny.

At least 19 recordsLinked to original sources

arXiv2026

Key Developer Roles and Organizational Coupling in Microservices: A Longitudinal Analysis

Microservice-based systems impose significant organizational coordination challenges, yet the role of individual developers in shaping organizational coupling (OC) remains underexplored. Prior work largely focuses on structural architectural aspects, leaving gaps in understanding how developer roles influence coordination dynamics over time. This study investigates how different developer roles contribute to OC in a large-scale microservices system. The analysis focuses on three key roles, namely Jacks, representing broad knowledge holders, Mavens, representing deep specialists, and Connectors, representing organizational bridges. A longitudinal repository mining analysis of GitHub data, including commits and issue and pull request interactions, is conducted to operationalize OC and quantify its evolution over time. The results show that Connectors are consistently associated with higher levels of OC, while the co-occurrence of multiple roles within the same developer further amplifies coupling effects. In contrast, Jacks and Mavens exhibit more localized and role-specific influences. These findings indicate that OC in microservices is primarily a role-driven phenomenon rather than an inevitable structural property, providing a foundation for role-aware organizational design and targeted decoupling strategies.

cs.SE↗

arXiv2025

Vision: An Extensible Methodology for Formal Software Verification in Microservice Systems

Microservice systems are becoming increasingly adopted due to their scalability, decentralized development, and support for continuous integration and delivery (CI/CD). However, this decentralized development by separate teams and continuous evolution can introduce miscommunication and incompatible implementations, undermining system maintainability and reliability across aspects from security policy to system architecture. We propose a novel methodology that statically reconstructs microservice source code into a formal system model. From this model, a Satisfiability Modulo Theories (SMT) constraint set can be derived, enabling formal verification. Our methodology is extensible, supporting software verification across multiple cross-cutting concerns. We focus on applying the methodology to verify the system architecture concern, presenting formal reasoning to validate the methodology's correctness and applicability for this concern. Additional concerns such as security policy implementation are considered. Future directions are established to extend and evaluate the methodology.

cs.SE↗

arXiv2025

UWB-PostureGuard: A Privacy-Preserving RF Sensing System for Continuous Ergonomic Sitting Posture Monitoring

Improper sitting posture during prolonged computer use has become a significant public health concern. Traditional posture monitoring solutions face substantial barriers, including privacy concerns with camera-based systems and user discomfort with wearable sensors. This paper presents UWB-PostureGuard, a privacy-preserving ultra-wideband (UWB) sensing system that advances mobile technologies for preventive health management through continuous, contactless monitoring of ergonomic sitting posture. Our system leverages commercial UWB devices, utilizing comprehensive feature engineering to extract multiple ergonomic sitting posture features. We develop PoseGBDT to effectively capture temporal dependencies in posture patterns, addressing limitations of traditional frame-wise classification approaches. Extensive real-world evaluation across 10 participants and 19 distinct postures demonstrates exceptional performance, achieving 99.11% accuracy while maintaining robustness against environmental variables such as clothing thickness, additional devices, and furniture configurations. Our system provides a scalable, privacy-preserving mobile health solution on existing platforms for proactive ergonomic management, improving quality of life at low costs.

cs.CV↗

arXiv2025

Generative AI for Software Architecture. Applications, Challenges, and Future Directions

Context: Generative Artificial Intelligence (GenAI) is transforming much of software development, yet its application in software architecture is still in its infancy, and no prior study has systematically addressed the topic. Aim: We aim to systematically synthesize the use, rationale, contexts, usability, and future challenges of GenAI in software architecture. Method: We performed a multivocal literature review (MLR), analyzing peer-reviewed and gray literature, identifying current practices, models, adoption contexts, and reported challenges, extracting themes via open coding. Results: Our review identified significant adoption of GenAI for architectural decision support and architectural reconstruction. OpenAI GPT models are predominantly applied, and there is consistent use of techniques such as few-shot prompting and retrieved-augmented generation (RAG). GenAI has been applied mostly to initial stages of the Software Development Life Cycle (SDLC), such as Requirements-to-Architecture and Architecture-to-Code. Monolithic and microservice architectures were the dominant targets. However, rigorous testing of GenAI outputs was typically missing from the studies. Among the most frequent challenges are model precision, hallucinations, ethical aspects, privacy issues, lack of architecture-specific datasets, and the absence of sound evaluation frameworks. Conclusions: GenAI shows significant potential in software design, but several challenges remain on its path to greater adoption. Research efforts should target designing general evaluation methodologies, handling ethics and precision, increasing transparency and explainability, and promoting architecture-specific datasets and benchmarks to bridge the gap between theoretical possibilities and practical use.

cs.SE↗

arXiv2025

Toward Organizational Decoupling in Microservices Through Key Developer Allocation

With microservices continuously being popular in the software architecture domain, more practitioners and researchers have begun to pay attention to the degradation issue that diminishes its sustainability. One of the key factors that causes the degradation of the architecture is that of the software architectural structure according to Conway's law. However, the best practice of "One microservice per Team", advocated widely by the industry, is not commonly adopted, especially when many developers contribute heavily across multiple microservices and create organizational coupling. Therein, many key developers, who are responsible for the majority of the project work and irreplaceable to the team, can also create the most coupling and be the primary cause of microservice degradation. Hence, to properly maintain microservice architecture in terms of its organizational structure, we shall identify these key developers and understand their connections to the organizational coupling within the project. We propose an approach to identify the key developers in microservice projects and investigate their connection to organizational coupling. The approach shall facilitate the maintenance and optimization of microservice projects against degradation by detecting and mitigating organizational coupling.

cs.SE↗

arXiv2025

Towards Change Impact Analysis in Microservices-based System Evolution

Cloud-native systems are the mainstream for enterprise solutions, given their scalability, resilience, and other benefits. While the benefits of cloud-native systems fueled by microservices are known, less guidance exists on their evolution. One could assume that since microservices encapsulate their code, code changes remain encapsulated as well; however, the community is becoming more aware of the possible consequences of code change propagation across microservices. Moreover, an active mitigation instrument for negative consequences of change propagation across microservices (i.e., ripple effect) is yet missing, but the microservice community would greatly benefit from it. This paper introduces what it could look like to have an infrastructure to assist with change impact analysis across the entire microservice system and intends to facilitate advancements in laying out the foundations and building guidelines on microservice system evolution. It shares a new direction for incremental software architecture reconstruction that could serve as the infrastructure concept and demonstrates early results from prototyping to illustrate the potential impact.

cs.SE↗

arXiv2025

Semantic Dependency in Microservice Architecture: A Framework for Definition and Detection

Microservices have been a key architectural approach for over a decade, transforming system design by promoting decentralization and allowing development teams to work independently on specific microservices. While loosely coupled microservices are ideal, dependencies between them are inevitable. Often, these dependencies go unnoticed by development teams. Although syntactic dependencies can be identified, tracking semantic dependencies - when multiple microservices share similar logic - poses a greater challenge. As systems evolve, changes made to one microservice can trigger ripple effects, jeopardizing system consistency and requiring updates to dependent services, which increases maintenance and operational complexity. Effectively tracking different types of dependencies across microservices is essential for anticipating the impact of such changes. This paper introduces the Semantic Dependency Matrix as an instrument to address these challenges from a semantic perspective. We propose an automated approach to extract and represent these dependencies and demonstrate its effectiveness through a case study. This paper takes a step further by demonstrating the significance of semantic dependencies, even in cases where there are no direct dependencies between microservices. It shows that these hidden dependencies can exist independently of endpoint or data dependencies, revealing critical connections that might otherwise be overlooked.

cs.SE↗

arXiv2024

Comparison of Static Analysis Architecture Recovery Tools for Microservice Applications

Architecture recovery tools help software engineers obtain an overview of the structure of their software systems during all phases of the software development life cycle. This is especially important for microservice applications because they consist of multiple interacting microservices, which makes it more challenging to oversee the architecture. Various tools and techniques for architecture recovery (also called architecture reconstruction) have been presented in academic and gray literature sources, but no overview and comparison of their accuracy exists. This paper presents the results of a multivocal literature review with the goal of identifying architecture recovery tools for microservice applications and a comparison of the identified tools' architectural recovery accuracy. We focused on static tools since they can be integrated into fast-paced CI/CD pipelines. 13 such tools were identified from the literature and nine of them could be executed and compared on their capability of detecting different system characteristics. The best-performing tool exhibited an overall F1-score of 0.86. Additionally, the possibility of combining multiple tools to increase the recovery correctness was investigated, yielding a combination of four individual tools that achieves an F1-score of 0.91. Registered report: The methodology of this study has been peer-reviewed and accepted as a registered report at MSR'24: arXiv:2403.06941

cs.SE↗

arXiv2024

Bottleneck-based Encoder-decoder ARchitecture (BEAR) for Learning Unbiased Consumer-to-Consumer Image Representations

Unbiased representation learning is still an object of study under specific applications and contexts. Novel architectures are usually crafted to resolve particular problems using mixtures of fundamental pieces. This paper presents different image feature extraction mechanisms that work together with residual connections to encode perceptual image information in an autoencoder configuration. We use image data that aims to support a larger research agenda dealing with issues regarding criminal activity in consumer-to-consumer online platforms. Preliminary results suggest that the proposed architecture can learn rich spaces using ours and other image datasets resolving important challenges that are identified.

cs.CV↗

arXiv2024

Detecting Hallucinations in Large Language Model Generation: A Token Probability Approach

Concerns regarding the propensity of Large Language Models (LLMs) to produce inaccurate outputs, also known as hallucinations, have escalated. Detecting them is vital for ensuring the reliability of applications relying on LLM-generated content. Current methods often demand substantial resources and rely on extensive LLMs or employ supervised learning with multidimensional features or intricate linguistic and semantic analyses difficult to reproduce and largely depend on using the same LLM that hallucinated. This paper introduces a supervised learning approach employing two simple classifiers utilizing only four numerical features derived from tokens and vocabulary probabilities obtained from other LLM evaluators, which are not necessarily the same. The method yields promising results, surpassing state-of-the-art outcomes in multiple tasks across three different benchmarks. Additionally, we provide a comprehensive examination of the strengths and weaknesses of our approach, highlighting the significance of the features utilized and the LLM employed as an evaluator. We have released our code publicly at https://github.com/Baylor-AI/HalluDetect.

cs.CL↗

arXiv2024

On the Challenges of Creating Datasets for Analyzing Commercial Sex Advertisements to Assess Human Trafficking Risk and Organized Activity

Our study addresses the challenges of building datasets to understand the risks associated with organized activities and human trafficking through commercial sex advertisements. These challenges include data scarcity, rapid obsolescence, and privacy concerns. Traditional approaches, which are not automated and are difficult to reproduce, fall short in addressing these issues. We have developed a reproducible and automated methodology to analyze five million advertisements. In the process, we identified further challenges in dataset creation within this sensitive domain. This paper presents a streamlined methodology to assist researchers in constructing effective datasets for combating organized crime, allowing them to focus on advancing detection technologies.

cs.LG↗

arXiv2024

Service Weaver: A Promising Direction for Cloud-native Systems?

Cloud-native and microservice architectures have taken over the development world by storm. While being incredibly scalable and resilient, microservice architectures also come at the cost of increased overhead to build and maintain. Google's Service Weaver aims to simplify the complexities associated with implementing cloud-native systems by introducing the concept of a single modular binary composed of agent-like components, thereby abstracting away the microservice architecture notion of individual services. While Service Weaver presents a promising approach to streamline the development of cloud-native applications and addresses nearly all significant aspects of conventional cloud-native systems, there are existing tradeoffs affecting the overall functionality of the system. Notably, Service Weaver's straightforward implementation and deployment of components alleviate the overhead of constructing a complex microservice architecture. However, it is important to acknowledge that certain features, including separate code bases, routing mechanisms, resiliency, and security, are presently lacking in the framework.

cs.SE↗

arXiv2024

Comparison of Static Analysis Architecture Recovery Tools for Microservice Applications

Architecture recovery tools help software engineers obtain an overview of their software systems during all phases of the software development lifecycle. This is especially important for microservice applications because their distributed nature makes it more challenging to oversee the architecture. Various tools and techniques for this task are presented in academic and grey literature sources. Practitioners and researchers can benefit from a comprehensive overview of these tools and their abilities. However, no such overview exists that is based on executing the identified tools and assessing their outputs regarding effectiveness. With the study described in this paper, we plan to first identify static analysis architecture recovery tools for microservice applications via a multi-vocal literature review, and then execute them on a common dataset and compare the measured effectiveness in architecture recovery. We will focus on static approaches because they are also suitable for integration into fast-paced CI/CD pipelines.

cs.SE↗

arXiv2023

The Microservice Dependency Matrix

Microservices have been recognized for over a decade. They reshaped system design enabling decentralization and independence of development teams working on particular microservices. While loosely coupled microservices are desired, it is inevitable for dependencies to arise. However, these dependencies often go unnoticed by development teams. As the system evolves, making changes to one microservice may trigger a ripple effect, necessitating adjustments in dependent microservices and increasing maintenance and operational efforts. Tracking different types of dependencies across microservices becomes crucial in anticipating the consequences of development team changes. This paper introduces the Endpoint Dependency Matrix (EDM) and Data Dependency Matrix (DDM) as tools to address this challenge. We present an automated approach for tracking these dependencies and demonstrate their extraction through a case study.

cs.SE↗

arXiv2023

End-to-End Test Coverage Metrics in Microservice Systems: An Automated Approach

Microservice architecture gains momentum by fueling systems with cloud-native benefits, scalability, and decentralized evolution. However, new challenges emerge for end-to-end (E2E) testing. Testers who see the decentralized system through the user interface might assume their tests are comprehensive, covering all middleware endpoints scattered across microservices. However, they do not have instruments to verify such assumptions. This paper introduces test coverage metrics for evaluating the extent of E2E test suite coverage for microservice endpoints. Next, it presents an automated approach to compute these metrics to provide feedback on the completeness of E2E test suites. Furthermore, a visual perspective is provided to highlight test coverage across the system's microservices to guide on gaps in test suites. We implement a proof-of-concept tool and perform a case study on a well-established system benchmark showing it can generate conclusive feedback on test suite coverage over system endpoints.

cs.SE↗

arXiv2023

One Microservice per Developer: Is This the Trend in OSS?

When developing and managing microservice systems, practitioners suggest that each microservice should be owned by a particular team. In effect, there is only one team with the responsibility to manage a given service. Consequently, one developer should belong to only one team. This practice of "one-microservice-per-developer" is especially prevalent in large projects with an extensive development team. Based on the bazaar-style software development model of Open Source Projects, in which different programmers, like vendors at a bazaar, offer to help out developing different parts of the system, this article investigates whether we can observe the "one-microservice-per-developer" behavior, a strategy we assume anticipated within microservice based Open Source Projects. We conducted an empirical study among 38 microservice-based OS projects. Our findings indicate that the strategy is rarely respected by open-source developers except for projects that have dedicated DevOps teams.

cs.SE↗

arXiv2023

Benchmarks for End-to-End Microservices Testing

Testing microservice systems involves a large amount of planning and problem-solving. The difficulty of testing microservice systems increases as the size and structure of such systems become more complex. To help the microservice community and simplify experiments with testing and traffic simulation, we created a test benchmark containing full functional testing coverage for two well-established open-source microservice systems. Through our benchmark design, we aimed to demonstrate ways to overcome certain challenges and find effective strategies when testing microservices. In addition, to demonstrate our benchmark use, we conducted a case study to identify the best approaches to take to validate a full coverage of tests using service-dependency graph discovery and business process discovery using tracing.

cs.SE↗

arXiv2023

Comparing 2D and Augmented Reality Visualizations for Microservice System Understandability: A Controlled Experiment

Microservice-based systems are often complex to understand, especially when their sizes grow. Abstracted views help practitioners with the system understanding from a certain perspective. Recent advancement in interactive data visualization begs the question of whether established software engineering models to visualize system design remain the most suited approach for the service-oriented design of microservices. Our recent work proposed presenting a 3D visualization for microservices in augmented reality. This paper analyzes whether such an approach brings any benefits to practitioners when dealing with selected architectural questions related to system design quality. For this purpose, we conducted a controlled experiment involving 20 participants investigating their performance in identifying service dependency, service cardinality, and bottlenecks. Results show that the 3D enables novices to perform as well as experts in the detection of service dependencies, especially in large systems, while no differences are reported for the identification of service cardinality and bottlenecks. We recommend industry and researchers to further investigate AR for microservice architectural analysis, especially to ease the onboarding of new developers in microservice~projects.

cs.SE↗