I have a problem where our current SDLC model is the V-model which is great for its verification/validation of all phases, but lacks the support for iterations. Spiral model on the other hand has iterations and fits, but does not focus on verification, validation and testing activities like the V-model.

Is it valid to just state were using modified spiral model which implements verification, validation and testing activities to all phases just like on V-model?

I havent found any SDLC model that would directly fit my needs and im unsure how much i can "invent" or combine by myself.

Ive thought about agile/scrum since theyre flexible and dont really lock in anything, but ive been instructed to avoid those terms at all costs.

  • Did the instruction also state why you need to stay away from agile and/or scrum? Jul 14, 2022 at 12:29
  • @BartvanIngenSchenau Mentioning those would make some audits difficult to pass and upper management/clients detest agile and scrum. Agile is seen as adhoc that does not produce rigid documentation that our clients desire.
    – LAL
    Jul 14, 2022 at 12:39

2 Answers 2


I don't see how the V-model doesn't have support for iterations.

The V-model only links test activities to development activities. It doesn't matter whether you're using sequential or iterative & incremental techniques to manage your endeavor, the V-model will still apply. Your system will have a concept of operations and using the system will prove it meets the concept of operations. You will have requirements and system architecture and system-level verification and validation activities will test conformance to those requirements. Your detailed design will identify components and your integration tests will ensure those components work together. Your implementation will have unit tests.

If you're following a sequential model, then you'll have a big requirements specification done up-front that you will use to develop system tests. If you're using an iterative and incremental (or Agile) model, then you'll have thin slices of requirements that you'll evolve over time, and evolve the system tests as the system evolves. In both cases, system verification and validation tests are explicitly linked to the system requirements.

You can just as easily link the verification side of the V to the activities in the spiral model or even agile methods.

  • From what ive read the V-model has two limitations. No iterations and no overlapping phases. All our phases overlap and finish just before delivery of final software. Since this question was closed as "opinion based" it sounds like i can just say our V-model has overlapping phases and iterations (due to multiple SW releases). Are these models really that flexible?
    – LAL
    Jul 15, 2022 at 5:33
  • @LAL, the V-model does not specify iterations, but it also doesn't forbid them. There is nothing stopping you from using the V-model inside each iteration of an iterative process. Jul 15, 2022 at 7:10
  • @BartvanIngenSchenau Got it. Do you have any books or good sources you can recommend that would clarify different models and their applications? Im responsible for our QA process, but learning by googling is often confusing.
    – LAL
    Jul 15, 2022 at 7:30

Probably you can't get fully out of Agile\Scrum... Have a look on SAFe (which is agile based, but better conforms your needs in validation\verification - due to it's flexibility on system level).

Eventually what you need is split verification and validation, from development. While delivery may run Kanban\Agile\Scrum\XP (choose relevant practices from any and give it any good name) at integration level you may keep maintaining strict process. SAFe would be a good baseline to understand how to get this done.

  • It does seem like i cant get fully out of agile since were already using kanban during development phase. Do you have any sources which would clarify SAFe implementation? I tried looking but did not find anything on how to replace our current V-model with SAFe. Im unsure how different phases of development are handled on SAFe and if its applicable to project level or just coding/implementation phase.
    – LAL
    Jul 14, 2022 at 12:03
  • You can review it here in more details scaledagileframework.com - Take a note that you may implement any process at the team level, while maintain needed verification and validation at ART level. Also please note Agile/Scrum/Kanban/XP is a family of similar frameworks (to some extend) - lots of development practices are shared.
    – Maksym
    Jul 14, 2022 at 12:16
  • Applicability of SAFe should be easy to clarify, but implementing is hard and require learning entire framework - so you put needed adjustments
    – Maksym
    Jul 14, 2022 at 12:23

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