Event Storming - System Design

"Event Storming in System Design" introduces an innovative workshop technique aimed at rapidly capturing and visualizing complex business processes. By leveraging collaborative efforts and visual representation with sticky notes, Event Storming enhances understanding and facilitates streamlined system design in software development.

What is Event Storming?

Event storming is a collaborative workshop method used in software development to explore and map out business processes or system behaviors.

• Participants use sticky notes to represent events, commands, and actions, helping to clarify business rules, identify key concepts, and uncover potential issues.
• It's effective for understanding complex domains and accelerating the design of software solutions by fostering communication and collaboration among stakeholders

Importance of Event Storming in System Design

Event Storming is crucial in system design for several reasons:

• Enhanced Collaboration:
  • During an Event Storming session, it is essential to involve people possessing the knowledge about domain, developers, and others, who play a crucial role in the creation of a new system.
  • As a result, all participants get a common vision of the system as a whole and details. This in turn results to the formulation of good system designs because of the synergy involved between the two.
• Rapid Insight:
  • Event Storming is formatted very fast and therefore encourages the participants to become very engaged in understanding the system’s structure, process, and interactions.
  • It provides a very quick understanding of the field to prevent and detect probable problems, holes and opportunities during design.
• Domain-Driven Design Alignment:
  • Event Storming can thus complement the methodology known as Domain-Driven Design (DDD), which proposes one of the most effective ways to develop software based on the main business domain.
  • This way the teams are in a position to observe the behavior and construct better and more systematically correct models in the domain thus enabling the creation of sophisticated and easily maintainable domains.
• Flexibility and Adaptability:
  • By capturing and sharing the evolving knowledge of the domain and the delivered artifacts.
  • Event Storming is usable at any level of the system design, from conceptual to technical one.
  • Due to the above characteristics, it can be used in numerous projects and domains of science and technology.
• Problem Discovery:
  • Event Storming outlines and visualizes the events and all the interactions between the elements within the system that is under design and lets teams check for the consistencies and or redundancies and or issues that may occur during the implementation of the solution.
  • Frequent and timely problem identification result in more successful and timely solutions.

Basic Concepts of Event Storming

Several basic concepts of event storming include:

• Domain Events:
  • It is a major event that takes place within the business environment to result in system transformation.
  • These may include “Order Placed,” “Payment Made,” and/or “Product Delivered”.
• Command:
  • A command is an operation or a desire that leads to a domain event occurring.
  • For example, the command that one user can use is “Place Order” and the event that occurs in response to it is the “Order Placed”.
• Aggregate:
  • An aggregate can be defined as a group of domain objects that should be manipulated as a single entity.
  • Aggregates are expected to be keeping the continuity of change intra-boundary.
  • For example, contents of an “Order” aggregate, might contain items, details of the customer, as well as payment details.
• Read Model:
  • A read model is used to model the state of the system with regards to querying and reporting on the state of the application.
  • They are often optimized for read operations to offer easy and fast access to the data that is required in those numerous user interfaces and reports.
• Bounded Context:
  • A bounded context specifies the scope within which a certain model can be used.
  • It assist in handling complexity since the domain is divided into subdomains that are easier to handle.
  • Every bounded context has its own language that is known as ubiquitous language and this language comes with rules.
• Policies:
  • They are the formal rules or regulations that are in force in a business relating to the system.
  • They define how the system should behave in response to a specific event or with a specific word or phrase.

Steps of Preparation for Event Storming

Preparation of the team is rather important in the case of Event Storming to reach high results. Here are the key steps:

• Step 1: Define Objectives:
  • Purpose of the session, what is expected to be achieved when the session is over.
  • Decide whether you are analysing the strategic business processes, certain functions of the system, or the intricate details.
  • This way the coordinator or teacher is able to ensure that, through the exercise of setting objective, the session achieves what it seeks to achieve.
• Step 2: Select Participants:
  • This should require the input of multiple people who are involved in the completion of the project such as, domain experts, developers, business analysts, product managers or any other personnel who are involved in the project.
  • The right combination of participants guarantees that all the views are taken into consideration, and all the nuances reflected in the domain are described as well.
• Step 3: Gather Materials:
  • Make sure you have the materials needed for the sticky note activity such as sticky notes, markers, large paper rolls or whiteboards.
  • For the online meetings it is necessary to provide the possibility of using digital collaboration platforms like Miro or MURAL.
  • Preparation of materials contributes positively to the effectiveness of the session that is being conducted.
• Step 4: Set Up the Environment:
  • Carry out arranging a conveniently comfortable, incidental-free environment suitable for collaboration.
  • Make sure the space that is provided for the activity is enough to allow the participants to walk and engage themselves with the model.
  • When conducting the sessions remotely, check that the participant has strong signals and that they are conversant with the gadgets to be used.
• Step 5: Pre-Workshop Briefing:
  • Remind participants about general ideas of Event Storming and the scheme of the next meeting. Some of the uses of the technique include.
  • An introduction of the technique or technique benefit might assist the participants understand what is in store for them hence be more receptive to the session.

The Event Storming Process

The Event Storming process typically unfolds in several stages, each with a specific focus and set of activities:

1. Big Picture Event Storming:

• Goal: For the sake of getting the overall picture of the system and its key processes.
• Process:
  • They start by noting down the domain events on small pieces of paper and placing them on a timeline which is preferably organized in ascending order of obviousness.
  • This aids in visual representations of the system and major processes especially the work flow of the entity.
  • Commands, aggregates, and policies are used in order to introduce context and specific information into the communication.
  • It plays a vital role in understanding the framework of the system and discovering further research options.

2. Process Level Event Storming:

• Goal: To look further into a particular process or to focus into related limited areas of a system.
• Process:
  • Increase theGranularity in a certain process or bounded context identifying the commands, the events, the aggregates, and the policies within this context.
  • This stage usually entails decomposing abstract high-level events into elements that are more detailed and distinguishing the relations between the aspects of the system.
  • This is because the understanding of the specific elements, required for different processes, allows indicating more detailed requirements and the necessary design elements.

3. Design Level Event Storming:

• Goal: To create detailed technical designs for implementation.
• Process:
  • Identify and map out the specifics of aggregates, commands, read models, and interactions.
  • This stage involves defining the structure and behavior of the aggregates, detailing the commands and their effects, and designing the read models for efficient querying and reporting.
  • The design level Event Storming provides a concrete blueprint for the implementation phase.

Best Practices for Effective Event Storming

To maximize the effectiveness of Event Storming, consider the following best practices:

• Facilitator Role:
  • Select an organized and experienced leader who will help members to have effective sessions in respect to the meeting.
  • This is a professional who ensures that the session is on track, the time is well divided and ensures that each member of the team gives their input.
• Inclusive Participation:
  • Make sure to get everybody involved so a variety of ideas and opinions is given.
  • And finally, Do not allow just one person to talk a lot, while others hardly get any chance to speak.
  • If there are different views, then it is possible to receive fuller and more suitable information.
• Iterative Approach:
  • Approach Event Storming as a cyclical one, gradually improving the model in the course of the subsequent sessions.
  • Such an approach facilitates refinement of the model through the integration of the current and past knowledge about the problem under consideration.
• Visual Clarity:
  • This is where one needs to be more careful and minimize the use of labels that are not easily understood and that may clutter up other items such as event and commands.
  • Don’t overcrowd and make sure that the model is very clear and well- comprehensible by all the stakeholders.
• Documentation:
  • Document the outputs of the session in a form that can easily be transferred to practice for emulation.
  • Documentation assists in the retention of the information passed during the session while also working as a roadmap for implementing and fine-tuning the ideas brought up during the session.

Using Event Storming in Business Environments

Event Storming has been successfully applied across various industries and use cases, including:

• E-Commerce:
  • Determining the mechanisms of order managers and payment processing systems.
  • Event Storming offers an opportunity to identify the customer path from product discovery to order placing, payment, and the receipt of the goods’ shipment.
  • They also define its interactions with the inventory management, customer support, and marketing systems.
• Banking:
  • Representing such financial stakings and customer relations as can be complex.
  • Event Storming is applied for creating applications and information systems in the sphere of account management, loan processing, fraud detection, and regulation.
  • It allows to find out such significant occurrences as transactions’ approval, transfers of funds, updates of the accounts, etc.
• Healthcare:
  • Improving the patient management and medical records information systems.
  • Event Storming helps in building processes for patient admission, appointments, treatment plans, and charging among others.
  • It also assists to establish relations between the actors involved, including the health care providers, patients and the insurance firms.

Digital Tools for Remote Event Storming

For remote or distributed teams, several digital tools facilitate Event Storming

• Miro:
  • An online collaborative tool that involves the use of a one board for diagramming and another board for creating sticky note exercises.
  • Some of the features which are available in Miro includes templates, real-time collaboration, and connectivity to other tools, which is why most of the time, remote Event Storming sessions incorporate Miro.
• MURAL:
  • Yet another tool for virtual whiteboard and that especially aimed at the teamwork as well as at brainstorming.
  • MURAL covers a lot of templates and tools for visual work and it’s possible to conduct Event Storming successfully remotely.
• Microsoft Whiteboard:
  • A part of Microsoft Office package, that allows teams to cooperated in the processes of creating documents, in real-time.
  • Microsoft Whiteboard enables users to draw, write, and post messages, notes or annotations on a virtual board or canvas.
• Zoom:
  • A synthesis of the videotelphony with screen vision and annotation possibilities.
  • Zoom is a tool that allows teams to perform Event Storming on the virtual space and include the video conferencing, sharing the screen, and annotations facilities.

Scaling Event Storming for Large Projects

Scaling Event Storming for large projects involves additional considerations:

• Modular Approach:
  • It is possible to divide the domain into smaller subdomains or equally, bounded contexts that are easy to handle.
  • Due to modularity, one module or bounded context can be examined and mapped individually; hence, handling complexity is much more consistent.
• Multiple Sessions:
  • In this case, use several, but intense Event Storming sessions, each aimed at particular part of the system.
  • This approach enables teams to go further in one specific line and make certain that all parts of the organizational structure have been searched through.
• Cross-Team Collaboration:
  • It will help in achieving coordinative communication between distinct groups from the different organizations that focus on the several aspects of the project.
  • The project’s interdependence of teams’ work following comprehensive documentation and meetings every few weeks helps in achieving consistency across the whole project.
• Consistent Documentation:
  • All the sessions should be documented in very elaborate and very standardized manner so as to uphold harmony and consistency.
  • Taking notes of the discussions is useful in ensuring that information acquired in every meeting is kept and gives account of which can be used in developing better plans and strategies to be implemented in future meetings.