Windra Swastika, et. : Web-Based Programming Assessment with A (October 2. Web-Based Programming Assessment with DeepSeek R1 AI Feedback System Windra Swastika1,*. Vincent Dwi Hartanto1, and Paulus Lucky Tirma Irawan1 1Informatics Engineering. Faculty of Technology and Design. Universitas Ma Chung. Malang. Indonesia Corresponding author: Windra Swastika . -mail: windra. swastika@machung. ABSTRACT The evaluation of programming assignments in computer science education is often timeconsuming and subjective when done manually by instructors. This study proposes an automated web-based code evaluation system that leverages Artificial Intelligence (AI) to provide immediate and objective The system is built with the Next. js framework for the user interface and integrates a Large Language Model (LLM). DeepSeek-R1, via the LangChain framework as the intermediary for AI Through this integration, the system automatically analyses student source code submissions against given programming tasks and grading rubrics, generating feedback and scores in real-time. Performance testing of the implemented system yielded an average response time of 5. 7 seconds, a throughput 86 requests per second, and a front-end load performance score of 78. User evaluation using the System Usability Scale (SUS) resulted in a score of 77, indicating a positive user experience. The system functioned effectively during trials, demonstrating that AI-driven code evaluation can accelerate and simplify the grading process in programming education while maintaining satisfactory accuracy and usability. These findings suggest that integrating LLMs into programming education platforms offers a scalable and effective approach to automated assessment, with significant potential to enhance learning outcomes and reduce the workload of instructors in academic environments. KEYWORDS Artificial Intelligence. Code Evaluation. Deepseek-R1. Large Language Model INTRODUCTION The algorithm course is one of the fundamental pillars in the curriculum of Informatics study programs. An algorithm is broadly defined as a finite sequence of well-defined, computer-implementable instructions to solve a class of problems . This course is crucial as it equips students with logical thinking skills, systematic algorithm design, and implementation in programming languages. As emphasized by various educators, computer programming is a skill that must be mastered by computer science students, making the learning and evaluation processes in this course essential for ensuring students truly understand the taught material . However, in practice, the evaluation and assessment of students' program code still face various problems. Providing feedback on programming assignments is a very tedious, error-prone, and time-consuming task for instructors, even in standard classroom environments . Additionally, manual assessment is often subjective and inconsistent, which poses a significant challenge in computer science education . Students often only receive final grades without clear and detailed feedback regarding deficiencies or errors in their program code, which occurs because the feedback provided is ineffective, thus not beneficial for students and cannot improve their performance . The lack of immediate. VOLUME 07. No 02, 2025 DOI: 10. 52985/insyst. constructive feedback is a significant barrier to student learning and improvement in programming courses. With technological development. Artificial Intelligence (AI) has presented innovative solutions in various fields, including education. Dewi . defines artificial intelligence as a field of study related to capturing, modeling, and storing human intelligence in an information technology system so that the system can be used as a decision-making process performed by humans. Zulkarnain and Yunus . emphasized that the use of AI technology in learning can serve as a powerful computational solution, where AI-powered technology can be used to assist teaching and evaluation A systematic review of AI applications in higher education further confirmed this trend, finding that AI is increasingly being applied across various educational domains including assessment, intelligent tutoring, and personalized learning . One significant development in AI is the emergence of Large Language Models (LLM. , which can understand and generate text in natural language as well as programming LLMs are large-scale language models trained on vast datasets, giving them extensive language understanding and knowledge without needing highly structured data to Windra Swastika, et. : Web-Based Programming Assessment with A (October 2. process and understand specific natural languages . Models like DeepSeek-R1 are examples of LLMs specifically designed to understand, evaluate, and provide automatic feedback on program code. Recent studies have shown promising results regarding the effectiveness of DeepSeek models in programming tasks. According to the model's developers. DeepSeek-R1 achieved high scores on mathematical and coding benchmarks, indicating that this model can outperform a significant percentage of human participants in programming competitions . Furthermore, comparative studies have demonstrated that DeepSeek shows competitive performance against other Large Language Models while offering significant advantages in terms of cost efficiency . One study found that DeepSeek outperformed ChatGPT in solving programming contest problems, with a correctness rate of 0. 5454 compared to ChatGPT's 0. By utilizing AI capabilities in data analysis and modelling, many new approaches have been proposed to measure student performance more accurately and efficiently . LLMs like DeepSeek-R1 can be integrated with LangChain, a framework that enables the development of AI-based applications in a modular and flexible manner. LangChain is an open-source framework that facilitates the creation of LLM applications with custom data, high scalability, and accelerated development processes . Therefore, a web-based program code evaluation platform was developed using the Next. This platform integrates LangChain to connect the user interface with the DeepSeek-R1 LLM, enabling automatic and interactive program code evaluation processes. With this system, instructors are expected to evaluate more easily while students receive beneficial feedback to improve their programming skills effectively and efficiently. Despite the growing body of research on AI-assisted programming assessment, existing solutions present several limitations that our system addresses. Traditional auto graders such as CodeRunner and AutoGrader rely primarily on static test cases and predefined rules, providing limited explanatory feedback beyond pass/fail indicators . While recent tools like GitHub Copilot for Education and ChatGPT-based assessment systems leverage large language models for code analysis, they often lack integration with learning management workflows and fail to provide structured, rubricaligned evaluations . Our system introduces three key innovations that distinguish it from existing approaches. First, we implement real-time, rubric-guided AI feedback that generates detailed explanations aligned with specific learning objectives, moving beyond binary correctness to provide educational insights. Second, our architecture integrates LangChain as a modular intermediary layer, enabling flexible LLM selection and prompt engineering strategies that can be adapted to different programming languages and assessment Third, we provide comprehensive scalability evidence through systematic load testing and economic analysis, demonstrating the practical viability of deploying AIVOLUME 07. No 02, 2025 DOI: 10. 52985/insyst. powered assessment at institutional scale. The use of DeepSeek-R1 specifically offers advantages in cost-efficiency and reasoning capabilities for programming tasks, as demonstrated by its competitive performance on coding benchmarks . Our contribution lies not merely in applying an LLM to programming assessment, but in creating an end-to-end educational platform that balances pedagogical effectiveness, technical performance, and economic II. RESEARCH METHOD This research uses a software engineering methodology aimed at designing and building a web-based system for automating source code evaluation using artificial intelligence (AI). The research was conducted with a structured approach through several interrelated stages as illustrated in Figure 1. Research Design The research adopts a development research methodology, which combines theoretical foundations with practical implementation to create and validate educational products . The study follows a sequential approach beginning with literature review, progressing through system requirements analysis, design, implementation, testing, and evaluation. Figure 1 illustrates the research methodology flowchart that guides the entire development process from initial conceptualization to final documentation. Figure 1. Research Flow Diagram The development process initiates with literature study to establish theoretical foundations and identify existing gaps in automated programming assessment systems. This phase involves comprehensive analysis of current AI-based evaluation techniques, learning management systems, and programming education methodologies. The literature review provides insights into state-of-the-art approaches and establishes the research novelty by identifying limitations in existing solutions. Windra Swastika, et. : Web-Based Programming Assessment with A (October 2. Following the literature study, the system requirements analysis phase determines functional and non-functional requirements for the platform. This analysis encompasses user requirements for both students and educators, technical specifications for AI integration, performance criteria, and security considerations. The requirements analysis ensures that the developed system addresses real educational needs while maintaining technical feasibility and scalability. System Design and Architecture The system design phase establishes the overall architecture and detailed specifications for the AI-powered assessment Figure 2 presents the activity diagram that illustrates the interaction between three primary actors: Students. System, and Educators. The architecture shows the complete workflow from user registration and authentication through AI-based evaluation and feedback delivery. natural language processing capabilities for code evaluation and feedback generation. The functional requirements include user authentication for both students and mentors, exam and assignment upload capabilities by mentors, student answer submission through web-based code editor, automatic AI evaluation using DeepSeek-R1, automatic feedback provision, mentor access to student assignments and AI evaluation results, optional additional mentor feedback, and comprehensive data storage to PostgreSQL database through Prisma ORM. Non-functional responsiveness and accessibility across various devices, optimal system performance with reasonable AI evaluation processing time, high system availability . /7 uptim. , and user-friendly interface design that is easily understood by both students and mentors. Database Design The database design employs a relational database model to manage system data efficiently. Figure 3 illustrates the Entity Relationship Diagram (ERD) that defines the relationships between core entities including Educator. Student. Exam. Quiz. ExamSubmission, and QuizSubmission. The database schema ensures data integrity through appropriate constraints, foreign key relationships, and normalization principles. Figure 2. Activity Diagram The system incorporates a web-based platform that facilitates seamless interaction between students and educators while integrating artificial intelligence for automated assessment. The design emphasizes modular architecture to ensure maintainability, scalability, and The platform utilizes LangChain as an intermediary framework to manage interactions with the DeepSeek-R1 large language model, enabling sophisticated VOLUME 07. No 02, 2025 DOI: 10. 52985/insyst. Figure 3. Entity relationship diagram The Educator entity stores instructor information including authentication credentials and profile data. The Student entity maintains learner information with similar authentication and profile attributes. The Exam entity represents assessment containers created by educators, while the Quiz entity defines individual programming problems within examinations. The ExamSubmission entity tracks student participation in Windra Swastika, et. : Web-Based Programming Assessment with A (October 2. examinations, and the QuizSubmission entity records detailed submission data including source code. AI-generated feedback, scores, and evaluation status. Implementation Methodology The system implementation follows an iterative development approach utilizing modern web technologies and The platform development incorporates responsive web design principles to ensure accessibility across various devices and screen sizes. The implementation integrates AI capabilities through API connections to language models, enabling real-time code evaluation and feedback The development process emphasizes considerations including user authentication, comprehensive error handling, logging mechanisms, and performance optimization techniques. The modular architecture facilitates independent development and testing of system components while maintaining overall system cohesion. Testing and Evaluation The testing methodology encompasses multiple phases including unit, integration, system, and user acceptance The evaluation phase includes performance metrics assessment. AI evaluation accuracy measurement, and user experience analysis using the System Usability Scale (SUS) . The SUS is a widely adopted and reliable tool for measuring perceived usability through a ten-item The evaluation phase includes performance metrics assessment. AI evaluation accuracy measurement, and user experience analysis. The testing process validates system requirements compliance and identifies areas for User feedback collection through surveys and usage analytics provides insights into system effectiveness and user satisfaction levels. The research methodology ensures systematic development of a comprehensive AI-powered assessment platform that addresses current limitations in programming education while providing innovative solutions for automated code evaluation and personalized feedback delivery. RESULTS AND DISCUSSION System Implementation Results The developed system successfully integrates all planned components into a functional web-based platform. The system architecture utilizes Next. js for both frontend and backend development, with PostgreSQL database managed through Prisma ORM, and DeepSeek-R1 AI model accessed via official API through LangChain framework. Several implementation adjustments were made from the original design: the student answer collection method was changed from file upload to direct code editor input for better VOLUME 07. No 02, 2025 DOI: 10. 52985/insyst. user experience and real-time processing capability. The user interface implementation closely follows the initial wireframe designs, with minor adjustments for improved usability. Figure 4 shows the main dashboard interface for students, displaying available exams with relevant information including course name, instructor, deadline, and completion Figure 4. Student dashboard interface The mentor interface provides comprehensive access to student submissions and AI evaluation results, as demonstrated in Figure 5. This interface allows mentors to review AI-generated feedback and provide additional manual feedback when necessary. Figure 5. Mentor evaluation interface AI Evaluation Implementation The AI evaluation system processes student submissions through a prompt engineering approach. The system constructs prompts using markdown format for better structure recognition by the AI model. Each evaluation request includes the programming language specification, problem statement, evaluation rubric, and student's code submission. The evaluation process generates three key outputs: detailed narrative feedback explaining the analysis and suggestions for improvement, quantitative score based on the provided rubric, and binary correctness status . rue/fals. Figure 6 illustrates the complete AI evaluation workflow from submission to result display. Windra Swastika, et. : Web-Based Programming Assessment with A (October 2. Figure 6. AI evaluation workflow Sample evaluations demonstrate the system's capability to provide constructive feedback. For a correct solution to a temperature conversion problem, the AI provided detailed analysis highlighting the proper implementation while suggesting minor improvements for edge case handling. For an incorrect solution with logical errors, the AI identified specific issues and provided guidance for correction without directly revealing the solution. Performance Testing Results Performance testing was conducted to evaluate system capabilities under various load conditions. The results are summarized in Table 1, showing key performance metrics obtained through different testing tools. TABLE I PERFORMANCE TESTING RESULTS Metric Average Response Time Minimum Response Time Maximum Response Time Throughput Load time performance System Usability Scale (SUS) Value 7 sec 2 sec Tool Used Grafana K6 Grafana K6 7 sec Grafana K6 8 req/sec Grafana K6 Google Lighthouse User survey The response time analysis shown in Table I indicates that while the average processing time of 5. 7 seconds is reasonable for AI-powered evaluation, there are occasional longer processing times that may require optimization for improved user experience. System Usability Evaluation The System Usability Scale (SUS) evaluation involved five student participants. The average SUS score of 77 indicates good system usability. According to established benchmarks, a SUS score above 68 is considered above average, and a score of 77 falls into the "Good" or "B grade" category, confirming a positive user reception . Qualitative feedback from participants revealed positive aspects including the clarity of AI feedback and the fairness of the partial credit scoring The average SUS score of 77 indicates good system usability, as scores above 68 are generally considered aboveaverage globally. This result suggests that the system provides VOLUME 07. No 02, 2025 DOI: 10. 52985/insyst. a satisfactory user experience for students in programming course contexts. Qualitative feedback from participants revealed positive aspects including clear and comprehensive AI feedback, helpful explanations for error correction, and fair scoring system that provides partial credit rather than binary pass/fail Areas for improvement identified include interface design enhancement, addition of code editor features like autocompletion, and faster AI processing times. AI Evaluation Accuracy and Human Agreement Analysis To validate the accuracy of AI-generated assessments, we conducted a systematic comparison between DeepSeek-R1 evaluations and expert human grading. A dataset of 20 student submissions across three programming problems . asic algorithms and medium-difficulty problem. was independently evaluated by one experienced programming instructors and the AI system. Table II presents the agreement analysis between AI and human evaluations. The scoring comparison shows strong correlation between AI and human assessments, with a Pearson correlation coefficient of 0. < 0. , indicating high linear relationship between the scoring systems. Cohen's Kappa coefficient of 0. demonstrates substantial agreement in classification of submissions into quality categories . xcellent, good, fair, poo. , surpassing the 0. 60 threshold considered indicative of substantial agreement . TABLE II PERFORMANCE TESTING RESULTS Metric Pearson Correlation Value Cohen's Kappa Mean Absolute Error (MAE) Root Mean Square Error (RMSE) Agreement within A10 Agreement within A5 3 point 1 point Interpretation Strong positive Substantial Average scoring Score prediction High practical Moderate strict The Mean Absolute Error of 7. 3 points . n a 0-100 scal. indicates that AI scores typically deviate less than 7. 3 points from human expert scores. The 88% agreement rate within A10 points demonstrates that the AI system provides practically equivalent assessments to human graders in the vast majority of cases. The 64% agreement within A5 points show reasonable precision for fine-grained scoring. AI Evaluation Quality Assessment The quality of AI-generated evaluations was assessed by programming course instructors to ensure alignment with academic standards. The evaluation criteria included logical Windra Swastika, et. : Web-Based Programming Assessment with A (October 2. explanation accuracy, alignment with teaching materials, information clarity, educational value of feedback, and potential for accelerating evaluation processes. Instructor feedback indicated that the AI explanations demonstrated good logical reasoning, though some cases could benefit from additional clarification. The system adequately accommodates general teaching materials, while specialized or customized topics may require supplementary The feedback provided was deemed sufficiently clear and met educational components enabling students to continue learning independently. Notably, instructors confirmed that the AI system significantly helps accelerate evaluation processes, with the recommendation that detailed rubrics be created to ensure more explainable assessment results and reduce potential subjective bias in evaluation. Token Usage and Cost Analysis Token usage analysis was conducted using a complex Object-Oriented Programming problem to simulate real-world usage scenarios. The test involved a library management system implementation requiring approximately 200 lines of Java code, representing typical final exam complexity. As shown in Table i, even for complex programming problems with lengthy solutions, the token usage remains well within DeepSeek-R1's maximum limit of 64,000 tokens per The cost analysis indicates that automated evaluation is economically viable for educational institutions, with each evaluation costing approximately $0. 003 or about Rp 51. TABLE i TOKEN USAGE AND COST Metric Input Token Output Token Total Token Input cost (USD) Output cost (USD) Total Cost (USD) Value 2,141 3,041 $0. $0. $0. IV. CONCLUSION The research findings demonstrate that our web-based automated code evaluation system successfully addresses the challenges identified in programming education. Through integration of DeepSeek-R1 LLM with LangChain and Next. js frameworks, we developed a platform that transforms how programming assignments are assessed and feedback is Our implementation reveals several key achievements. The evaluation demonstrates the system's readiness for institutional deployment. The substantial AI-human agreement (Cohen's Kappa = 0. and strong correlation . = . validate assessment accuracy comparable to expert human graders. The also system maintains operational stability with a 5. 7-second average response time, which VOLUME 07. No 02, 2025 DOI: 10. 52985/insyst. proves acceptable for educational contexts where immediate feedback enhances learning outcomes. The throughput capacity of 10. 86 requests per second, combined with successful scalability testing up to 150 concurrent users, indicates the platform can support typical classroom environments without performance bottlenecks. Student acceptance proved encouraging, with a SUS score of 77 reflecting positive user experiences. Participants particularly valued the comprehensive feedback quality and fair scoring approach that awards partial credit rather than binary pass/fail results. The load time performance score of 78 further validates the technical implementation choices made during development. From an institutional perspective, the economic analysis shows promising sustainability. Each evaluation costs approximately $0. 003, making the technology financially viable for widespread educational adoption. This costeffectiveness, combined with the significant time savings reported by instructors, presents a compelling case for implementation across programming curricula. Perhaps most importantly, academic validation from programming instructors confirms that AI-generated feedback maintains educational standards while reducing evaluation The system consistently provides constructive guidance that helps students understand their mistakes and improve their coding skills, which represents the core pedagogical goal. However, our work also identifies areas requiring continued Interface design improvements, enhanced code editor functionality, and faster processing times emerged as priorities from user feedback. Additionally, implementing comprehensive classroom management features would better serve institutional needs. This research contributes practical evidence that AIpowered programming assessment can successfully bridge the gap between educational demands and technological The developed system not only demonstrates technical feasibility but also validates the educational value of automated evaluation when properly implemented with appropriate oversight and quality controls. ACKNOWLEDGMENTS The authors would like to express their sincere gratitude to Universitas Ma Chung for providing financial support through the Learning Innovation Grant (Hibah Inovasi Pembelajara. that made this research possible. We also extend our appreciation to the Faculty of Technology and Design. Universitas Ma Chung, for providing the necessary infrastructure and academic environment to conduct this Special thanks to the students and faculty members who participated in the system testing and evaluation phases, whose valuable feedback contributed significantly to the improvement of the developed system. Windra Swastika, et. : Web-Based Programming Assessment with A (October 2. AUTHORS CONTRIBUTION Windra Swastika: Conceptualization, methodology design, project supervision, system architecture review, validation of results, review and editing of manuscript, funding Vincent Dwi Hartanto: System design and implementation. AI integration development, database design, user interface development, system testing and evaluation, data collection and analysis. Paulus Lucky Tirma Irawan: Project administration, technical guidance, system validation, review of AI evaluation quality, mentorship throughout development process, manuscript review and editing. COPYRIGHT This work is licensed under a Creative Commons Attribution-NonCommercialShareAlike 4. 0 International License. Ugale. Durgesh, et al. "Student Performance Prediction Using Data Mining Techniques. " International Research Journal of Engineering and Technology (IRJET) 7. 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