Skip to content
KPI Science News
ISSN 2617-5509 · e‑ISSN 2663-7472 Open Access · CC BY 4.0
Vol. 142 · Issue 1 · 2026 Mar 30, 2026 article

ENGINEERING OF SOFTWARE SYSTEMS BASED ON SNAPSHOT-CENTRIC CQRS WITH EVENT SOURCING ARCHITECTURE

DH
Dmytro Hruzin Corresponding Dnipro National University, Faculty of Physics, Electronics and Computer Systems, Dnipro, Ukraine Ukraine
OL
Oleksandr Lytvynov Dnipro, Ukraine, Oles Honchar Dnipro National University, Faculty of Physics, Electronics and Computer Systems, Dnipro, Ukraine Ukraine
PublishedMar 30, 2026
PDF (Ukrainian)
KPISN 1 VOL 142 · 1
VOL 142 · ISS 1 · 2026 View issue

Abstract

Background. Command Query Responsibility Segregation (CQRS) with Event Sourcing (ES) is a widely adopted solution for designing scalable and high-performance information systems. However, classical CQRS with ES implementations are often associated with increased complexity in development and maintenance. Objective. The goal of this study is to simplify the development and maintenance of software systems built on CQRS with ES by introducing an alternative variation of the architecture. Methods. The classical architectural variation was analyzed, and the components that increase the complexity of system development and maintenance were identified. Based on this analysis, an alternative architectural variation (mCQRS) is proposed, that uses a lower-complexity component set. The solution is based on a relational database in which aggregate state snapshots are treated as the source of truth, thereby reducing implementation and maintenance complexity and facilitating potential migration to other architectural variations. Results. Representative test projects were developed for both the classical and the proposed CQRS with ES variations. Cyclomatic complexity values for a typical command execution workflow (120 for Classical CQRS and 82 for mCQRS) indicate a 31.67% decrease in complexity. Performance measurements show that server response time for queries is identical for both variations (44 ms), whereas the end-to-end time to reach system consistency for commands is 268 ms for Classical CQRS and 347 ms for mCQRS, corresponding to a 22.76% decrease in performance. Despite this degradation, write-operation throughput remains high in the context of established industry practices. Conclusions. The proposed approach improves the efficiency of development and maintenance and reduces the required level of developer expertise; it is suitable for systems in which write-operation performance is not critical

Keywords

#CQRS #Event Sourcing #Software Architecture

References

  1. M. Fowler, “Patterns of Enterprise Application Architecture”, Addison-Wesley Professional, 2002. - 560 p. ISBN: 978-0321127426. Retrieved from: https://raw.githubusercontent.com/ZoranLi/Books1/master/Patterns%20of%20Enterprise%20Application%20Architecture.pdf .
  2. B. Woolf and G. Hohpe, “Enterprise Integration Patterns: Designing, Building, and Deploying Messaging Solutions”, Addison-Wesley Professional, 2004. - 736 p. ISBN: 978-0321200686. Retrieved from: https://github.com/ivanarandac/Books/blob/master/Enterprise%20Integration%20Patterns%20-%20Designing%2C%20Building%20And%20Deploying%20Messaging.pdf .
  3. E. Evans. “Domain-Driven Design: Tackling Complexity in the Heart of Software”, Addison-Wesley Professional, 2004. - 534 p. ISBN: 978-0321125217. Retrieved from: https://github.com/gmoral/Books/blob/master/Domain%20Driven%20Design%20Tackling%20Complexity%20in%20the%20Heart%20of%20Software%20-%20Eric%20Evans.pdf .
  4. Neal Ford, Rebecca Parsons, Patrick Kua and Pramod Sadalage, “Building evolutionary architectures (2nd ed.)”, 2022, O'Reilly Media, Sebastopol, CA, 262. Retrieved from: https://www.thoughtworks.com/content/dam/thoughtworks/documents/books/bk_building_evolutionary_architectures_second_edition_free_chapter.pdf .
  5. Y. Zhong, “Using Event Sourcing and CQRS to Build a High Performance Point Trading System”, E-Business and Applications: 5th International Conference, Bangkok, 25 February 2019: proceedings. - New York: Association for Computing Machinery, 2019. - P. 16-19. DOI: 10.1145/3317614.3317632. Retrieved from: https://doi.org/10.1145/3317614.3317632 .
  6. D. Betts, J. Dominguez, G. Melnik, F. Simonazzi and M. Subramanian, “Exploring CQRS and Event Sourcing: A Journey into High Scalability, Availability, and Maintainability with Windows Azure (1st ed.)”, 2012, Microsoft patterns & practices. Retrieved from: https://download.microsoft.com/download/e/a/8/ea8c6e1f-01d8-43ba-992b-35cfcaa4fae3/cqrs_journey_guide.pdf .
  7. M. Fowler, “CQRS”, [Electronic resource] Retrieved from: https://martinfowler.com/bliki/CQRS.html .
  8. G. Young, “CQRS Documents by Greg Young”, [Electronic resource] / G. Young. - Retrieved from: https://cqrs.files.wordpress.com/2010/11/cqrs_documents.pdf .
  9. G. Young, “Event Centric: Finding Simplicity in Complex Systems”, Addison-Wesley Professional, 2017. - 560 p. ISBN: 978-0321768223. Retrieved from: https://books.google.com.ua/books/about/Event_Centric.html?id=pA2xuAAACAAJ&redir_esc=y .
  10. H. Taylor, A. Yochem, L. Phillips et al., “Event-Driven Architecture: How SOA Enables the RealTime Enterprise”, Addison-Wesley Professional, 2009. - 272 p. ISBN: 978-0321591388. Retrieved from: https://www.oreilly.com/library/view/event-driven-architecture-how/9780321591388/ .
  11. M. Overeem, M. Spoor, S. Jansen et al., “An empirical characterization of event sourced systems and their schema evolution - Lessons from industry”, Journal of Systems and Software. - 2021. - Vol. 178, Issue 4.
  12. DOI: 10.1016/j.jss.2021.110970.
  13. Retrieved from: https://doi.org/10.1016/j.jss.2021.110970 .
  14. K. Truyers. “Introduction to Domain Driven Design, CQRS and Event Sourcing”, 2013 [Electronic resource] Retrieved from: https://www.kenneth-truyers.net/2013/12/05/introduction-to-domain-driven-design-cqrs-and-event-sourcing/ .
  15. V. Vernon. “Implementing Domain-Driven Design”, Addison Wesley, 2013. - 656 p. ISBN: 978-0321834577. Retrieved from: https://ptgmedia.pearsoncmg.com/images/9780321834577/samplepages/0321834577.pdf .
  16. General Data Protection Regulation [Electronic resource]. - Retrieved from: https://gdpr-info.eu/ .
  17. N. Korkmaz, M. Nilsson, “Practitioners' view on command query responsibility segregation: thesis‚ MSc Information Systems”, Lund University: School of Economics and Management, - 2014. - 53 p. Retrieved from: https://lup.lub.lu.se/luur/download?func=downloadFile&recordOId=4864802&fileOId=4864803 .
  18. O. Lytvynov, D. Hruzin, “On the migration of Domain-driven Design to CQRS with Event Sourcing software architecture”, Information Technology Computer Science Software Engineering and Cyber Security. - 2024. - Vol. 1, Issue 1. - P. 50-60.
  19. DOI: 10.32782/IT/2024-1-7.
  20. Retrieved from: https://doi.org/10.32782/IT/2024-1-7 .
  21. P. Revesz, “Relational Databases”, Introduction to Databases. - London: Springer, 2010. - Chapter 4. - 743 p.
  22. DOI: 10.1007/978-1-84996-095-3_3.
  23. Retrieved from: https://doi.org/10.1007/978-1-84996-095-3_3 .
  24. M. L. Brodie, M. Stonebraker, “Ai S. DARWIN: On the Incremental Migration of Legacy Information Systems”, 1995.
  25. Retrieved from: https://dsf.berkeley.edu/papers/S2K-93-25.pdf .
  26. M. Breitmayer, L. Arnold, S. La Rocca et al., “Deriving Event Logs from Legacy Software Systems”, Lecture Notes in Business Information Processing - 2023. - Vol. 468. - P. 409-421.
  27. DOI: 10.1007/978-3-031-27815-0_30.
  28. Retrieved from: https://doi.org/10.1007/978-3-031-27815-0_30 .
  29. D. Comartin, “Snapshots in Event Sourcing for Rehydrating Aggregates” [Electronic resource] Retrieved from: https://codeopinion.com/snapshots-in-event-sourcing-for-rehydrating-aggregates/ .
  30. O. Evsyukov, “The Bermuda Aggregate. And the Rescue of the Drowning”, [Electronic resource] Retrieved from: https://youtu.be/Br4TL-486ZM?t=1500 .
  31. O. Dudycz, “Snapshots in Event Sourcing” [Electronic resource] Retrieved from: https://www.eventstore.com/blog/snapshots-in-event-sourcing .
  32. DBB Software's official company site [Electronic resource]. - Retrieved from: https://dbbsoftware.com/ .
  33. G. Young G. “Versioning in an Event Sourced System”, [Electronic resource] Retrieved from: https://leanpub.com/esversioning .
  34. S. Kleanthous, “Event immutability and dealing with change” [Electronic resource] Retrieved from: https://www.eventstore.com/blog/event-immutability-and-dealing-with-change .
  35. Z. Zheng, Shaoan Xie, Hong-Ning Dai et al., “An Overview of Blockchain Technology: Architecture, Consensus, and Future Trends”, Conference: 6th IEEE International Congress on Big Data.
  36. DOI: 10.1109/BigDataCongress.2017.85.
  37. Retrieved from: https://doi.org/10.1109/BigDataCongress.2017.85 .
  38. R. Laigner, A. Almeida, W. K. Assunção et al., “An Empirical Study on Challenges of Event Management in Microservice Architectures”, in An Empirical Study on Challenges of Event Management in Microservice Architectures,
  39. DOI: 10.48550/arXiv.2408.00440.
  40. Retrieved from: https://doi.org/10.48550/arXiv.2408.00440 .
  41. P. R. G. Vasconcellos, V. M. Bezerra, C. P. Bianchini, “Applying Event Sourcing in a ERP System: A Case Study”, XLIV Latin American Computer Conference, S√£o Paulo, 1-5 October 2018: proceedings. - IEEE, 2018. - P. 80-89.
  42. DOI: 10.1109/CLEI.2018.00019.
  43. Retrieved from: https://doi.org/10.1109/CLEI.2018.00019 .
  44. D. K. Pandiya, N. G. Charankar, “Optimizing Performance and Scalability in Micro Services with CQRS Design”, International Journal of Engineering Research & Technology. - 2024. - Vol. 13, Issue 4.
  45. DOI: 10.17577/IJERTV13IS040284.
  46. Retrieved from: https://doi.org/10.17577/IJERTV13IS040284 .
  47. B. Wu, D. Lawless, J. Bisbal et al., “The Butterfly Methodology: a gateway-free approach for migrating legacy information systems”, 1997.
  48. DOI: 10.1109/ICECCS.1997.622311.
  49. Retrieved from: https://doi.org/10.1109/ICECCS.1997.622311 .
  50. M. Breitmayer, L. Arnold, S. La Rocca, “Deriving Event Logs from Legacy Software Systems”, 2023. DOI: 10.1007/978-3-031-27815-0_30. Retrieved from: https://doi.org/10.1007/978-3-031-27815-0_30 .
  51. G. Salvatierra, C. Mateos, M. Crasso, “Legacy System Migration Approaches”, 2013. DOI: 10.1109/TLA.2013.6533975.
  52. Retrieved from: https://doi.org/10.1109/TLA.2013.6533975 .
  53. G. Young, Link to GitHub repository [Electronic resource] - Retrieved from: https://github.com/gregoryyoung .
  54. M. Driscoll, “The Publish-Subscribe Pattern”, wxPython Recipes: A Problem - Solution Approach. - Apress, 2017. - Chapter 4. - 369 p.
  55. DOI: 10.1007/978-1-4842-3237-8_4.
  56. Retrieved from: https://link.springer.com/chapter/10.1007/978-1-4842-3237-8_4?utm_source=researchgate.net&utm_medium=article .
  57. P. Shaddel, “Understand and Implement Long-Polling and Short Polling in Node.js”, [Electronic resource] Retrieved from: https://levelup.gitconnected.com/understand-and-implement-long-polling-and-short-polling-in-node-js-94334d2233f3 .
  58. L. G. Cretu, “Event-driven replication in distributed systems”, India Software Engineering: the 4th Annual Conference, Thiruvananthapuram Kerala, 24-27 February 2011: proceedings. - New York: Association for Computing Machinery, 2011. - P. 95-98. DOI: 10.1145/1953355.1953367.
  59. Retrieved from: https://doi.org/10.1145/1953355.1953367 .
  60. “Practical and focused guide for survival in post-CQRS world. Projections.”, [Electronic resource] Retrieved from: http://cqrs.wikidot.com/doc:projection .
  61. D. Hruzin, Link to Zenodo repository, [Electronic resource] Access mode: https://zenodo.org/records/18263117 . DOI: 10.5281/zenodo.18263116. Retrieved from: https://doi.org/10.5281/zenodo.18263116 .
  62. T. J. McCabe, “A Complexity Measure”, IEEETransactions on Software Engineering. - 1976. -Vol. SE-2, Issue 4. - P. 308-320.
  63. DOI: 10.1109/TSE.1976.233837.
  64. Retrieved from: https://doi.org/10.1109/TSE.1976.233837 .
  65. SonarQube Cloud official site [Electronic resource] Retrieved from: https://www.sonarsource.com/products/sonarcloud/ .
  66. D. Hruzin, Link to SonarQube scan report, [Electronic resource] Retrieved from: https://sonarcloud.io/component_measures?metric=complexity&selected=dmitryhruzin_CQRS-variations-test%3Atypescript%2Fapps&id=dmitryhruzin_CQRS-variations-test .
  67. D. Hruzin, Link to GitHub repository, [Electronic resource] Retrieved from: https://github.com/dmitryhruzin/CQRS-variations-test/blob/main/scripts/run-measurement.js .
  68. S. Gayathri Devi, Dr K. Selvam, “An abstract to calculate big O factors of time and space complexity of machine code”, Conference: International Conference on Sustainable Energy and Intelligent Systems (SEISCON 2011), Jan. 2021,
  69. DOI: 10.1049/cp.2011.0483. Retrieved from: https://doi.org/10.1049/cp.2011.0483 .
  70. S. Burckhardt, “Principles of Eventual Consistency (Foundations and Trends(r) in Programming Languages)”, Now Publishers, 2014. - 170 p. ISBN: 978-1601988584.
  71. Retrieved from: https://www.microsoft.com/en-us/research/wp-content/uploads/2016/02/final-printversion-10-5-14.pdf .
§ 06 — Related

Similar articles in this journal

Related peer-reviewed studies published in this journal.
View all issues

AN APPROACH TO CONSTRUCTING AN INFORMATIVE FEATURE SPACE OF TECHNICAL INDICATORS FOR FINANCIAL PROCESSES BASED ON NEURAL NETWORK MODELS

Roman Tertychnyi, Denys Chuprin, Petro Bidyuk

Background. Financial time series are characterized by nonlinearity, non-stationarity, and a high level of noise, which significantly complicates their modeling and…

#informative feature space construction approach #technical indicators #Parkinson volatility #neural networks
10.20535/kpisn.2026.3.359610

Similar Articles

1-10 of 14

You may also start an advanced similarity search for this article.