Somewhere in the overlap between software development, process improvement and psychology

Posts tagged “requirements

Epics or Integration Scenarios?

Graphical Integration Scenario example

Many teams I’ve worked with struggle to make sense of their huge backlogs of stories, struggle to explain the scope of a release and current work – and most importantly, struggle to explain how the stories they’re working on contribute to business value!

All of these problems are killers when it comes to joining up what a development team is doing to a corporate portfolio, governance and milestones. Features and business benefits seem to be too high level, stories seem to be to low level.


 Epics

A common approach to trying to solve these problems is to use “epics”. Originally intended to just be another type of story (one that was too big for a sprint) “epics” are now commonly used in a requirements hierarchy by teams and organizations. I’ve seen loads of backlogs where every story had an epic “parent” – sometimes even a 1-1 mapping from epics to stories(!!!!). I know that some process frameworks recommend this approach, but I don’t and here’s why:

Stories can just be on a backlog

Stories don’t have to have a parent. A backlog made up of stories is just great, it doesn’t need a hierarchy that’s a Work Breakdown Structure using some agile-y sounding words to hide the fact. A backlog isn’t a gantt chart, stop trying to turn it into one by stealth!

Actual epics are useful for teams

“Epics” in their original form were simply stories too big for a sprint, sometimes that just creeps up on you so it’s useful to be able to tear up a big story and replace it with some smaller ones. By formalizing a Feature -> Epic -> Story hierarchy as an “agile at scale” process I’ve seen corporate processes become protectionist over epics, trying to use them to fix scope, counting and metricating them to the extent that teams can’t simply discover some of their stories are epics.

Bigger stories need more than a sentence

I know that a story can have more elaboration than the standard form of “as a user I want to…” but few stories in the wild have more than a sentence (you’re often lucky if you find some with acceptance criteria). I find that describing how various stories contribute together (especially when across several teams and/or systems) to deliver business value I need more than a sentence. I often need a diagram or a paragraph or two.

“Epics” sound silly

What’s in a name? Would a rose by any other name smell so sweet? Probably. Names shouldn’t be that important and yet they are, what we call things has a significant impact on how people represent them. “Epics” are part of the money spinning agile movement’s language. They either sound silly to businesses or as a way to pretend they’re doing “agile at scale” by adopting the term for their portfolio requests.

I like Integration Scenarios more

Ok, so this is clearly subjective and personal but that’s kinda my point. I don’t use process elements because someone told me to, and I don’t think that something like Integration Scenarios are always better than epics. I prefer to pick and choose different tools for different jobs. In my experience Integration scenarios are frequently a better tool for scoping, elaborating and agreeing  end-to-end threads across a system or system-of-systems so they’re one of my “go to” tools.


So what are Integration Scenarios?

Originally from Holistic Software EngineeringIntegration Scenarios

Integration Scenarios describe an end to end workflow across a Product or Product Family. Integration scenarios are threads across a number of low level requirements such as user stories that collectively deliver Business Value. They are ideally suited to describing the scope of Releases and providing the input for integration testing necessary to achieve higher levels of acceptance.

Integration Scenarios can also be used to manage cross-cutting Non-Functional Requirements and drive the discovery of Architectural Mechanisms.

Integration Scenarios provide the context for discussions around User Stories

Integration SceExample of graphical Integration Streamnarios can be described in a number of ways, ranging from textual to graphical depending on the nature of the system and the best way to achieve clarity. In all of these examples we recommend using a meaningful title, not “Integration Scenario”!

One of our favorite ways is to draw an activity diagram of user interactions using GUI mockups in the nodes with references to features/use cases/stories as appropriate. We do not recommend strictly following a diagram format but using the visual or textual elements that will communicate the scenario as effectively as possible. Story-boarding can also be an effective way of describing Integration Scenarios.

When using a graphical view we recommend including links to stories or systems that are covered by the scenario and adding rich graphics to standard modeling notation to increase communication.

Example of textual Integration Scenario Integration Scenarios using textual formats are best described as a narrative with links to contributing stories or systems.

They should ideally be no more than a couple of paragraphs that describe interactions between actors across a number of stories. Sometimes adding extra alternative or exceptional flows can be useful, in the style popularized by use cases, but if there’s a lot of “flow logic” involved then we recommend using a diagrammatic form (e.g. workflow) to avoid convoluted textual documents. Similarly adding a non-functional section indicating non-functional requirements or constraints that apply across the stories making up the scenario can be useful.

Integration Scenarios describe the dynamics between stories and how they collectively contribute to delivering business value. To that end we recommend highlighting and directly linking to the stories that make up the integration scenario. In this way Integration Scenarios add context to the mass of user stories and provide a sound basis for scoping a system, describing a release, functional architectural mechanisms, integration testing, and product acceptance.

Regardless of format we recommend that Integration Scenarios are described from the user perspective and focus on achieving business value. The choice of formats should be driven by the type of Product being developed (e.g. graphical/user facing vs. back end service) and further influenced by team experience and available tooling. We strongly advise not being concerned with the constraints imposed by formal modeling languages, the communication is important not the notation.

Example of simple graphical list view of an Integration ScenarioSometimes we wish to use Integration Scenarios as part of diagrams, even workflow/activity diagrams (e.g. for Value Stream Analysis) in which case the full text version might be a bit big. In these situations we recommend using a “zoomed out” view which just lists a title and the related stories. In fact this “elided” form of an Integration Scenario is sometimes useful for simply gathering up a collection of stories into a larger chunk for planning purposes. Story lists in these diagrams don’t have to be exhaustive, just indicative.

Practicality

Textual Integration Scenarios can be crafted in and decent rich text editor that allows for hyperlinks. We recommend trying to keep them short since the detail of the requirements should be in lower level stories or UX designs/storyboards. Instead the Integration Scenario focuses on the dynamics between requirements. A good rule of thumb is that they should be only a couple of paragraphs, and at their biggest if alternates/exceptions and nonfunctionals are included they should only be 2 or 3 pages. Creating a large number of fully documented Integration Scenarios prior to any development effort is a very bad idea as it will introduce the problems inherent in waterfall development, however elaborating the Integration Scenarios for a Release prior to development iterations/sprints or continuous flow development (with customer representation and team representation) is an excellent way to align collective understanding of scope and requirements.

Each Release should have no more than a couple of Integration Scenarios in it, if there’s more and they are not too interdependent then they can be delivered in separate Releases enabling earlier feedback cycles, (even if they are internal Releases rather than operationally deployed customer release.

Links to other elements

The H-ModelIntegration Scenarios provide a mid-level requirement type, higher than User Stories but lower than Portfolio Requests containing a lot more information than a Feature. As a result Integration Scenarios provide a unit of incremental business value which can be used for Release Planning, tying in milestones for programme/portfolio tracking and governance.

Because Integration Scenarios are constructed in a narrative form that describes a scenario, tried and tested scenario based testing methods can be applied for Integration testing.

Integration Scenarios also provide a useful starting point for understanding Solution Architecture, in the case of Product Families or systems of systems,  and even System Architecture in terms of indicating structure and identification of mechanisms. It is possible to resonate architectural structure with Integration Scenario structure although there is a risk of inappropriately introducing a Homomorphic force to the architecture.

By aligning Integration Scenarios with Integration Streams, Releases and Milestones we can focus the various views of Portfolio Management, Programme Management, Project Management, Architecture, Delivery, Quality, Deployment, Acceptance and and Business Change onto Releases at the center of the H-Model de-conflicting business management and technical delivery. Providing a context for requirements, planning and delivery Integration Stories are a common currency for the entire IT organization to work with.

Integration Modeling

Example of an Integration ModelIntegration Scenarios can also be used as part of Integration Modeling (creating scope diagrams) to indicate which actors/systems sets of requirements interact with, helping to clarify overall scope and identify potential gaps in scope.

If using Integration Modeling we recommend color coding Integration Scenarios based on priority (e.g. Musts, Shoulds etc.).

A Scoping Diagram is used to draw a picture of the primary requirements and users/interacting systems.

Read more: Scoping Diagram


What are your experiences of “Epics”, “Integration Scenarios”, “Scoping Use Cases” or other alternatives?

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What is agile architecture?

Agile ArchitectureArchitecture is a high level view of a system in the context of its environment, dependencies, technology, structure and behavior.

Architecture must be solid, useful and beautiful.

Software architecture is typically hard to define as the term software architecture is used to describe many facets of software structure, behaviour, design, activity and documentation. The concept of software architecture is also relevant at different levels of a system as the components of one system become a reusable platform for the next system. Ultimately the emergent behavior caused by layers of architectural dependencies and reuse can be difficult to predict.

Architecture is a simplification of the system, used to communicate the nature of that system and guide its development. However, architecture is more than just a diagram, it is grounded in technical context describing technology stacks, standards adopted, common ways of doing things (mechanisms), how non-functional requirements are met and the elements that will meet functional requirements. Architecture provides a shape and look and feel to the internals of a system that are the foundation for the ultimate external behavior.Da Vinci's Virtuvian Man

The idea of an “Architect” role with such a broad focus is analogous to that of a structural architect concerned with buildings. Indeed in 25 BCE Vitruvius (a well known Roman writer and architect who inspired Leonardo Da Vinci, hence the Vitruvian Man ) described an architect as:

The ideal architect should be a man of letters, a mathematician, familiar with historical studies, a diligent of philosophy, acquainted with music, not ignorant of medicine, learned in the responses of jurisconsults, familiar with astronomy and astronomical calculations.

Virtuvius is famous for stating that architecture must be solid, useful, beautiful (De architectura). The same three qualities relate to software architecture. Despite architecture being a fine balance between a subtle science and an exact art we must realise it is only useful if it is aligned to requirements and becomes executable.

Architecture, not documentation

In line with one of the founding Principles of Holistic Software Architecture I:

Value working software in the form of quality releases from short development cycles over comprehensive documentation, business analysis and enterprise architecture documentation.

Choosing how much architectural work is necessary up-front and especially how much architectural documentation is necessary is difficult.

Traditional document focused development methods promoted large up-front effort to detail, in document or model form, the architecture and system design prior to development. As well as the inherent risk extension issues in waterfall processes this could often cause “analysis paralysis” where architecture work was seen as an endless diagram drawing exercise.

Agile methods focus on working software over documents and designs, however this doesn’t mean that no documents or designs should be produced. It is almost always useful to have some description of an architecture before development even if it’s just a statement that the team’s usual architecture will be used as otherwise team members won’t even know which language to start writing in.

Good architecture addresses how we’ll resolve the major technical risks, communicates between the team the overall structure of the solution and works out how our solution will meet the functional and non-functional requirements. Knowing when we’ve worked out enough architecture so that we’ve reduced the complexity of the problem into manageable sizes for the team is a difficult challenge.

Levels of architectural formality

Doing too much architectural analysis or elaboration, either through abstract design and modelling or practical spiking (writing small amounts of throwaway code to demonstrate the feasibility of a technical approach or architectural idea) will slow down a development project and increase the risk of wasted work. Value is only achieved once working systems are in the hands of the customers/users.

Alternatively not doing enough architectural analysis can lead to significant architectural refactoring during a projects lifetime, as key requirements can’t be met based on the current architecture, again leading to wasted work and slowing down the project.

When doing up front architecture, especially in the form of documents and models, we need to be careful to consider architectural work in the context of the team’s definition of done. Typical levels of done don’t normally include “analysed”, “architected” or “designed”. Although these terms might be meaningful to describe internal team development states they do not constitute working software and are only a step on the way to creating value.


What is Fringe Testing?

Fringe testing is testing the unusual cases, the things that weren’t written down, weren’t predictable and weren’t obvious. In short it’s the kind of thing inventive, creative humans are good at.
Use Case basic flowWhen we’ve got requirements they’re often written in a form that states the normal way something will go, like a basic flow in a use case (or similar). Testing this might be useful but if it doesn’t work then the developer who wrote it clearly owes everyone a doughnut because after writing it, or finishing writing it, the very first thing that should be tried is going through the basic flow. In fact it’s a good candidate for automation and testing it should be considered part of the development team’s lowest levels of their definition of done.

Use Case Alternate FlowsUse Cases are normally elaborated in terms of more than just a basic flow with a set of alternative or exceptional cases or scenarios. You might consider each of these scenarios as Use Stories – I quite like this way of working with both Use Cases to make a high level scope diagram and User Stories for actually elaborating the requirements and acceptance criteria (see Use Case vs. User Story). The thing is, if it’s been written down in the requirements then the team should be testing it as a matter of course, the probability of finding defects in these flows is again pretty low. If they’re written as stories and implemented incrementally with acceptance criteria then it’s even more unlikely as they’re not much different from the basic flow. Just another story that should be developed and tested as part of the lowest levels of getting things done.

Use Case FringesThe fringe cases are the weird things that weren’t written down, that are odd ways through the requirements and are the places where the quality risks probably lie. Coming up with these is what real professional testers are good at and what proper test techniques are good for. Testing the basic paths of everything is less useful.

I’ve often thought that one way to simulate a user using my app is to take a scatter gun approach to clicking and pressing buttons in an app, because I think algorithmically, users often don’t. Many “normal” usages of your software may actually be fringe cases because things aren’t necessarily always used as designed. Of course that makes for a good argument for simpler interfaces (both GUIs and APIs).

So “Fringe Testing” is simply testing the unusual paths through your software, the places that most likely are the highest quality risks. Of course the most “fringey” cases are often the cross requirement paths, the end to end scenarios, that users take through your software or set of integrating components. As for traditional testing… I think it’s dead.

Quality ConfidenceI’ve previously blogged on the Quality Confidence metric being a useful lead indicator for software quality. One common question I’ve had on that is “Are you expecting us to fully test every requirement?”. The simple answer is “no”, testing should be focussed on the fringe cases to put an expensive resource where it’s most valuable. The Quality Confidence measure requires you to assert when you have enough coverage, for me that’s when you feel you’ve got a handle on the quality risks by testing a mix of important flows, risky stories and weird fringe cases – the rest I cover with simple professional development which always covers verification as part of development.


Scaled Agility: The Project Forum

This blog is an extract from the Project Forum practice: Holistic Software EngineeringThe Project Forum

When it might be appropriate

  • In situations where multiple competing stakeholder groups with different agendas are required to work together
  • In situations where multiple product groups need to collaborate on a bigger outcome
  • Where there is a conflict in direction, resource management/ownership or scope between collaborating groups
  • System of systems development

What is it?

The Project Forum is an application of agile philosophy to large project structures. Rather than impose a hierarchy of decision making from the Project Manager downwards the Project Forum is a virtual team in the middle of all stakeholders.

The Project Forum is a self-organising democratic group that balances competing voices and concerns, owns high level scope and architecture, runs the high level release train and performs integration activities for the product.

Use of the Project Forum practice does not prevent any communication directly between contributing groups it only provides a vehicle for that conversation when it’s relevant for the wider project.

From Traditional to Agile at ScaleThe Project Forum practice is an example of Agile at Scale combining social business practices, technical software practices and ways of working to make a simple way of doing big complicated bits of work.

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Simple software project measures

I’m not a big fan of metrics, measures, charts, reporting and data collection. I’m not terribly impressed by dashboards with 20 little graphs on showing loads of detailed information. When I’m involved in projects I want to know 3 simple things:

  • How quick are we doing stuff?
  • Are we on track or not?
  • Is the stuff good enough quality?

There can be some deep science behind the answers to those questions but at the surface that’s all I want to see.

Organisations need to know that teams are delivering quality products at the right pace to fit the business need. To achieve this goal teams need to be able to demonstrate that their product is of sufficient quality and that they can commit to delivering the required scope within the business time scales. If the project goal may not be achieved then the business or the team need to change something (such as scope, resources or time scales). This feedback mechanism and the open transparent communication of this knowledge is key to the success of agile delivery.

The goal of delivering quality products at the right pace can be measured in many complex ways however, when designing the Project Forum agile at scale practice we looked at just 3 measures. In fact I should probably call them 2.5 measures as the throughput/release burnup can be considered mutually exclusive (if you’re continuous flow or iterative). The most important measure is people’s opinions when you go and talk to your team.

Simple Measures Dashboard

Note: in the measures section I often refer to “requirements” as a simple number, this could be a count, a normalised count, magnitude, points, etc. it doesn’t matter what’s used so long as it’s consistent.

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What does “Agile at Scale” mean?

There’s a lot of talk in the process improvement industry about the meaning of “agile at scale”, devops, lean and agile for a number of reasons. One reason that I’ve seen in successful agile organisations is that as development maturity increases with true agile adoption bigger problems present themselves. This is the natural progression of the science of development, what used to be considered complex (like Object Orientation) is now normal, a commodity. Innovation in ways of working is happening at the organisational, cross-team, cross-product level.

For me agile at scale (I’ve got fed up of the quotes already) means a couple of different things:

  • Repeating agile successes embodied in a team across an organisation (scaling out?)
  • Applying agile thinking to cross-product projects
  • Applying agile and lean thinking to development organisations
  • Applying agile and lean thinking to high assurance environments like medical, security, financial, safety critical, audited, regulated businesses.

Agile and lean? Yep, both with lower case letters. I’m not particularly interested in ideological approaches to software development, I believe strongly in taking the best bits of whatever processes, techniques, practices etc. you find externally, mixing them up with internal practices and ways of doing things to develop simple, pragmatic approaches to ways of working. Both agile and lean schools of thought promote minimising unnecessary work, shorter delivery cycles and higher quality, continuously learning lessons and empirical decision making.

The agile manifesto gave us:

Individuals and interactions over processes and tools
Working software over comprehensive documentation
Customer collaboration over contract negotiation
Responding to change over following a plan

That is, while there is value in the items on
the right, we value the items on the left more.

Some great practices have evolved for applying agile and lean thinking like scrum, kanban etc. However all of the complex organisations I’ve worked with have found that there’s still space for more thinking in terms of how to run a software business, how to deal with big complex system-of-system problems, multiple competing stakeholder sets, programme and portfolio management etc. Not surprising really because the agile movement wasn’t about trying to do any of that stuff.

However organisations who are successful with agile transformations want to apply the successful open and honest philosophy behind the agile manifesto to other parts of their business as well as bigger and bigger projects and programmes because the results of “doing agile” (I promise I’ll stop with the quotes soon!) are so attractive when it’s done well, namely:

  • Shorter delivery cycles, higher quality
  • Deep engagement between customers and development teams leading to respect, collaboration and better morale
  • Quick identification of when things are starting to go wrong

Consider the following model, not uncommon amongst large organisations:

Diagram of nominal large inter-dependant organistion structure

This represents a typical software department or vertical section of a software department with a portfolio that provides the funding for work. Big portfolio’s are normally broken down into a number of programmes which in turn may levy high level requirements onto organisations (organisational sub-divisions that own multiple products) which may affect both legacy and new product development. Often within a vertical section of a business there will be many cross-dependencies in terms of requirements, technical dependencies etc. For many large businesses this picture is overly simplistic, indeed I’ve not included things like projects, component teams and a variety of business organisation constructs like product centres, feature teams etc.  So how do you apply agile and lean philosophy to this lot and more?

You can’t simply repeat the same practices recursively throughout an organisation to deal with larger scale complexity.  Imagine a chain of scrum-of-scrums, daily stand-ups at every level (at the same time, or staggered to allow representation up the chain?), sprint plans at programme level etc. What about if the business is regulated, audited, security focussed, high risk financial, safety critical, etc.

Ok, so what’s agile at scale then?

Agility at Scale is applying the spirit of agility and lean thinking if not the letter to these bigger problems. It’s about:

  • Valuing individuals and interactions, encouraging collaboration, reducing layers of communication over processes, tools and hierarchy
  • Valuing working software in the form of quality releases from short development cycles over comprehensive documentation, business analysis, enterprise architecture documentation
  • Valuing customer, business, developer and operations (see DevOps) collaboration over contract negotiation
  • Valuing good governance, transparency and honesty in progress, plans, costs and impediments over regular reporting
  • Valuing responding to change over following a plan at all levels of the business

(Borrowed from the Holistic Software Manifesto)

Agility at scale is focussed simply on reducing unnecessary bureaucracy, reducing time to market and improving value.

So how do you achieve it?

The application of:

Of course each of those (and more!) is a complex can of worms in itself. A lot of these higher scale practices are only just emerging from high maturity complex (post-)agile organisations but in time more of those things will turn into links.

A good example of  “Agile at Scale” in action is the Project Forum practice

As always this blog is  a stream of consciousness so please, let me know your opinion?


Use Case vs. User Story

Use Cases are too big to fit into a sprint/iteration! User Stories are so fine grained there’s too many too keep track of! Where’s the big picture? How to we define releases? Argh!!! I don’t know which to use!

Personally I tend to use both. I don’t think there’s any conflict between Use Cases and User Stories, in fact they’re rather complementary. Here’s how and why….

A few years ago I delivered a presentation at an agile software development conference entitled “Do requirements still matter?”. The short answer was “yes”. Most descriptions of agile iteration start with having a backlog, prioritising etc. etc. But where does the backlog come from? My answer: the Backlog Fairy; obviously.

The Backlog Fairy

Of course requirements still matter, they’re how we get a common understanding between customers and development teams of what we need to do. They’re the units by which we can incrementally build systems. In the rush to adopt agile processes a lot of teams have forgotten that they still need to start up with some lightweight analysis of scope and risk.

One of the things Use Cases are great at is capturing the big picture, showing a simple diagram of stick people and blobs that people who’ve never heard of UML can happily discuss in terms of what big bits of functionality are in and out of the system and who’s going to do them. The humble Use Case diagram. Not so easy to do that with a massive list of small stories.

However Use Cases can often be a bit too big to fit into a single development cycle but since they’re made up of a lot of different scenarios they’re easy to slice up into smaller bits. This is where I often use stories.

The advantage of Use Cases defining the scope is they’re nice chunky things to estimate and prioritise in a first pass. Of course as we get going we’ll estimate and prioritise stories for sprints/iterations but Use Cases help us prioritise requirements into Releases.

So I use a Use Case diagram to describe the high level scope of the thing to be developed. This normally takes about 5minutes to sketch. Then I use the Use Cases identified by the diagram (not documents, just the ovals on the diagram) to focus discussion on deriving stories (or use case slices) for development and testing within a sprint/iteration.

Sometimes stories turn up that don’t really fit into the early Use Case model, this is a rather good thing as it lets us challenge the understanding of scope. Does the story not fit in because it’s not really in line with the customers priorities and needs, it’s a cross-cutting or architectural concern or because we’ve missed some important part of the scope? All are important things to understand.