Software Engineering – from the Trenches

This post presents a practical guide of what happens during a typical Agile iteration – a sort of play-by-play for each role in the team, day by day. Please open the attached spreadsheet which models the day-by-day activities of a 2-week Agile development iteration, and describes the main activities for each role during this 10-day cycle of work. In addition, we will highlight how to successfully string iterations together, without any dead time; as the success of any given iteration is driven by preparation that has to take place in earlier iterations.

This is intended as a guide, rather than a prescription. While each iteration will have its own pace – a successful release will follow a sequence not too different from the one presented here.

Golden Rules

Each company is different, each project is different, each team is different, each release is different, and each interpretation of Agile is different. The following states the immutable principles to which I personally adhere.

• Once Engineering and Product Owner agree on the deliverables of an iteration, they are frozen for this iteration
  • Engineering must deliver on time
  • Features cannot be changed, added, or re-prioritized
  • Only exception is a “customer down” escalation of a day or more
• Engineering delivers “almost shippable” quality code at the end of the iteration
• Each release is self-contained: all the activities pertaining to a given user story must be completed within the iteration, or explicitly slated for another iteration at the start of the iteration
  • E.g.: QA, unit tests, code reviews, design documentation, update to build & deployment tools, etc
• Dev & QA engineers scope their individual tasks at the beginning of each iteration. The scope and deliverables of the iteration are based on these estimates.
  • Engineers are accountable to meet their own estimates

The above implies that Engineers must plan realistically by
(a) accounting for all activities that will need to take place for this iteration, and
(b) accounting for typical levels of interruptions and activities not specifically related to the project (scheduled meetings, questions from support, beer bashes, vacations, etc).

Estimates must be made with the expectation that we are all accountable to meeting them. This sounds like a truism, except that it is rarely applied in practice.

Day by Day

Before the Start of an Iteration

Preparation and planning prior to an iteration are critical to its success. As the spreadsheet highlights, the Product Manager spends the majority of his/her time during a given iteration planning the next iteration, by

(a)  Prioritizing the tasks to be delivered in the next iteration
(b)  Documenting the user stories to the level of detail required by developers
(c)  Reviewing scope with Project Manager and Tech Lead

Pre-requisites at the Start of a Release

The following must be delivered to Engineering at the start of a release. The Product Owner, Project Lead and Tech lead are responsible for providing

• “A” list of user stories to be implemented during the release
• Detailed specs of the “A” list user stories
• Design of the “A” list features sufficient to derive the coding  and QA tasks necessary to implement the features
• Estimated scope for each feature – rolling up to a target completion date for the iteration

These estimates are “budgetary”. Final estimates are given by the individual engineers.

Day 1 – Kick-Off

The whole team gets together and kicks-off the iteration: the PM presents the “A” list features to Eng, and the Tech Lead presents the critical design elements. Tasks are assigned tentatively.

During the rest of the day, engineers review the specs of their individual tasks, with the assistance of PM and Tech Lead.  This results in tasks entered into Jira, with associated scope and individual plans for the iteration.

The Project Lead combines all tasks into a project plan (using artifacts of his/her choice) to ensure that the sum of all activities adds up to a timely delivery of the iteration. The Project Lead also identifies any critical dependency, internal and external, that may impact the project.

A delivery date is computed from the individual estimates, and the team (lead by Product Owner, assisted by Project Manager and Tech Lead) iterates to adjust tasks and date

Day 2 – Deliverables are Finalized

Day 1 activities continue if necessary – resulting into a committed list of deliverables and a committed delivery date

The team, lead by Project Manager, also agrees on how the various tasks will be sequenced to optimize use of resources, and to front-load deliverables to QA as much as possible.

Developers start coding, QA engineers start writing test cases and/or writing automation tests

Day 6  – V1 Spec of the Next Iteration

By Day 6, the Product Manager provides the V1 Spec of the next iteration.

V1 Spec is a complete spec of all the user stories that the Product Owner estimates can be delivered in the next iteration. Typically, V1 will contain more than can be delivered, in order to provide flexibility in case some user stories are more complex than originally thought to implement.

During the remainder of the release, the Tech Lead (primarily) will work with the Product Owner to flesh out the details of the next release, to design the key components of the next release to a degree sufficient to be able to (a) list out the tasks required to implement the user stories, (b) estimate their scope, and (c) ensure that enough details has been provided for developers and QA engineers.

During the discussions of the next release, the Project Lead will identify any additional resources that will need to be procured, whether human or physical.

Day 7 – Release to QA

Release to QA means more than “feature complete”. It means feature complete and tested to the best of the developers’ knowledge and ability (see below).

Day 9 – Code Freeze

By Day 9, all bugs must have been fixed, so that the QA team can spend the last day of the iteration running full regression tests (ideally automated) and ensuring that all new features still work properly in the final build

By that time, the content and scope of the next release has been firmed up by Product Owner, Tech lead, and Project Manager, and task are tentative assigned to individual engineers.

Day 10 – Show & Tell

At the end of the last day of the iteration, Eng demos all the new features to the PM, the CEO and everyone in the company we can enroll.

We then celebrate.

Tools and Tips

Sequencing Iterations

• Depending on the complexity of the user stories, the Tech Lead (and other developers) may need to spend all of their time doing design, and may not be able to contribute any code.
• It is sometimes more productive to write automation tests once a given feature is stable. As a consequence, the QA team may adopt a cycle where they test manually during the current iteration and then automate the tests during the next iteration (once the code is stable)
• Exceptions to “almost shippable” are things like performance and stress testing, full browser compatibility testing, etc.
  • These tasks are then planned in the context of the overall release, and allocated to specific iterations

Release Duration

The duration of a given iteration is at the discretion of the team. It is strongly recommended that iterations last between 2 and 4 weeks.  It is also recommended that the duration of iteration be driven by its contents, in order to meet the Golden Rules. There is nothing wrong with a 12- or a 17-day iteration.

Start on Wednesday

Similarly, the starting day of the iteration is up to the team. Starting on a Wednesday offers several advantages:

• The iteration does not start on a Monday -). Mondays are often taken up by company & team meetings.
• Iteration finishes on a Tuesday rather than a Friday. Should the iteration slip by a day or two, it can be completed on Wednesday, or Thursday if need be. This means that the QA team is not always “stuck” having to work weekends in order to meet the deadline, nor do they have to scramble to make sure that developers are available during the weekend to fix their bugs, as would be the case if the iteration started on Monday
• By the second weekend of the iteration, the team will have good enough visibility into its progress, and determine whether work during the weekend will be required in order to meet the schedule.

Specs

The artifacts, format and level of details through which specs are delivered to Engineering is a matter of mutual agreement between Product Owner and Engineering, recognizing that Engineering is the consumer of the specs. As such, it is Engineering  who determines the adequacy of the information provided (since Engineering cannot create a good product from incomplete specs).

Specs must be targeted for QA as well as Dev. In particular, they must be prescriptive enough so that validation tests can be derived from them. For example they may include UI mockups, flow charts, information flow diagrams, error handling behavior, platforms supported, performance and scaling requirements, as necessary.

Release to QA

While the QA team has the primary responsibility of executing the tests that will validate quality, developers own the quality of the software (since they are the ones writing the software). As a consequence, when developers release to QA, they must have tested their code to ensure that no bugs of Severity 1 or 2 will be found by QA (or customers) – unless they explicitly agree in advance with the QA team that certain categories of tests will be run by QA.

Regardless of who runs the tests, the “release to QA” milestone is only reached when enough code introspection and testing has been performed to warrant confidence that no Severity 1 or 2 bugs will be found.

Releasing to QA

Developers and QA can agree on how code will be released to QA. While the spreadsheet shows one Releate to QA  milestone, this was done for clarity of presentation. In practice, it is recommended that developers release to QA as often as possible. Again, this should be driven by mutual agreement.

Furthermore, each developer must demonstrate to his/her QA colleague that the code works properly before the code is considered to be released. This demo is accompanied by a knowledge transfer session, where the developer highlights any known limitations in the code, areas that should be tested with particular scrutiny, etc.

Estimating Scope Accurately

One of the typical debates is whether time estimates should be measured in “ideal time” (no interruptions, distractions, meetings), or “actual time” (in order to account for the typical non-project-related activities). This is a matter of personal preference – what counts is that everyone in the team uses the same system.

I prefer to use “Ideal time”: each engineer keeps 2 “books” within an iteration: the actual iteration work – scoped in “ideal time”, and a “Other Activities” book, where all non-project-related activities are accounted for. This presents the advantages of (a) using a non-varying unit to measure the scope of tasks so that you can compare across people, project, time, and (b) having a means to track “non-productive time” on your project – and thus have data on which to drive decisions (e.g. pleading management for less meetings)

Click here to get the spreadsheet

Timing is Everything

Product Management delivering complete specifications in a timely fashion greatly improves the productivity of the Engineering team (Complete being relative the type of specifications – as we discussed in the previous blog). The more precise the information provided at the start of each phase (scoping, release or iteration), the more efficient and accurate will the resulting development work be.

This sounds boringly obvious, but I have seen the contrary scenario over and over again, where business leaders grumble that the Engineering team is not productive, while failing to provide more than a PowerPoint level specification at the start of  releases. As a consequence, developers spend the first third to half of the release working with the Product Managers to define the specs, instead of writing code – or even worse, developers start writing code without spec, and then having to do it over once the specs have been thought through.

Scoping is a 2-way Commitment

Another pitfall to avoid is “scope-creep”. While the name itself would imply that it should be avoided at all costs (who wants to be creepy?), scope creep is an all-too-common occurrence

Scope creep, on the surface, appears to stem from good intentions (we want to meet every customer request – even last minute ones), yet it is one of the most demoralizing behaviors for the Engineering team – akin to continuously pushing back the finish line, after the start of a race.

In order to avoid scope creep, we (Engineering) need to remind the business team that based on the information provided during the scoping phase, Engineering reserved a set of resources for the duration of the release, and committed to deliver the feature set in the allotted time. This in turn creates an implicit contract that the scope of the release – will be bound by the amount of resources allocated to the release. While changes are expected as we get closer to the release start, and even once the release has started, the business team can’t forget that there are only 24 hours in a day, and that no matter how cool it would be to add another 25% functionality, asking the Engineering team for such an increase in scope flies in the face of the process: If we could really do 25% more, we’d have said so the first time during the scoping phase.

In summary, once Engineering  allocates resources for a release and commits to deliverables and schedules, the business team, in turn, must commit to keep the scope of the release commensurate to the resources allocated.

Use the Right Artifacts for the Job

As we replaced Waterfall development process with Agile Software development, we also replaced Market/Product Requirement Documents with User Stories. I have to admit that I don’t get that part, or rather that I find that sometimes user stories are the best vehicle to express customer requirements, and other times, straight requirements do a better job.

For example, when a workflow needs to be implemented, nothing beats a flow chart or a state diagram to define it – we can dispense with the user story on the 3×5 card.

Write Things Down

There is no dispute that face to face discussions are the fastest way to nail down a user story. Often the expected behavior is self-evident from the software implementation itself. However, we must remember that multiple constituencies need to reach common understanding on the software’s behavior: not only the Product Champion and developers, but also, QA, support, services, etc.

Again, there is no way that more than 2 people can reach the same understanding of how a workflow should perform, or what a report is meant to compute unless it is written down, preferably in pictorial form

Technical Risk Must Be Eliminated Prior to Scoping

The business team expects estimates that are fairly accurate – say within 10%. You can see eyes roll when you present  your estimates and then add that the estimate is accurate within 30% … and it’s a fair reaction. As a consequence, time must be invested in research, design and/or prototyping, in order to reach the desired level of accuracy. Sometimes, we need to invest the time to build a prototype in order to validate a design or an architecture. While this initially may appear to be a prohibitive price to pay, a much much higher price would be paid if one embarks on a release, only to miss the deadline by a month or more, because we found out that the original design was inadequate.

Managing Perceptions

Which scenario is best?:

(A)  Promise to deliver 12 features and end up delivering 10 – OR -

(B)  Promise to deliver 9 features and end up delivering 9

In my experience, Scenario (A) is a perceived failure, while (B) will be perceived as a success.

If you agree with me, then you will want to think hard about your iteration plan, and about what features you implement in which iteration. Naturally, the later the iteration within the release, the more likely it is that its features will not be implemented (either because of schedule slips, or changes in priorities). Consequently, plan low-impact features for the last release(s); this way you’ll have to option of jettisoning them if necessary while still nailing the committed schedule. Conversely, if you high-impact features for the end, your only choices will be to disappoint — by taking them out in order to meet the schedule, or to disappoint — by forcing a schedule slip.

In conclusion, software development is a team activity – not only within the Engineering team but also with the business team: Engineering depends on the business team to create actionable specifications early enough before a release, to control the scope to a level commensurate to resources and time available, and to use artifacts that are relevant to the information to be conveyed.