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The rate at which team progresses sprint by sprint
Agile focuses on making software development more flexible by delivering smaller chunks of work frequently and lean focusses on making the entire process sustainable through continuous improvements.
Lean operates on the model of build-measure-learn. Lean prefers to use Kanban as its way of working
Anything that does not add value to the customer is considered waste. It could be extra inventory, additional checks, extra code, frills and features that are not used etc.
Kanban uses digital or physical boards to represent the team’s unique process. The work represented by cards move from left to right representing the progress. So at any given point of time, the organization can view the progress, capacity, productivity, and efficiency.
To, achieve continuous improvement, it is important to track metrics or KPIs. Kanban boards provide enough data on this aspect. Such as how many work items are delivering in 1 sprint; how many works in progress items are we able to handle without impacting velocity and what could be ways to improve the capacity.
A Kanban is like a flash card carrying all the information about the status of your work and the work required to be done on the product at each stage of the software development cycle. In simple terms, it classifies your work in three categories, TO DO -> WORK IN PROGRESS -> DONE.
The advantage of using Kanban is
Kanban works on three principles
In Kanban, with online document features you can do things like:
While using Kanban, the best way to track progress is Cumulative Flow Diagram. It replaces burndown/burnup chart for Kanban teams.
Kanban tells you more about how to manage the flow of work rather than how to release the work. However, there are few steps that might be helpful while releasing work or product in Kanban. They are:
True. Yes, all the work items that have moved past backlog and not yet shipped to Production are WIP [Work in progress]
It is generally 1 to 1.5 times of the total team count. So, if team size is 4, max 6 items can be in progress at any given time.
The horizontal division on a Kanban board to represent various stages of the pipeline is known as swim lane.
Throughput is the number of items passing through a system or process at any given time. So the formula is WIP average multiplied by the average cycle time of the pipeline.
Cycle time is the time between 2 releases. For example: if release 1 was on 1st Jan and the second release was on 15th Jan then cycle time is 14 days.
Lead time is the time between the start of processing of the order until delivery. For example, Release 1 happened on 1st Jan and release 2 started on 2nd Jan and got released on 15th Jan. so lead time is 13 days.
Cycle time is the total time including waiting time and lead time. Whereas lead time is the time when processing started and finished.
Lead time + wait time = cycle time.
Kanban’s basic strength lies in its simplicity and ability to visualize. That is why it is most famous. However, we should leverage concepts of KPIs and flow to make sure we are utilizing the full power of this concept.
If the team is asking for more work because they think they can do more then obvious choice is to allow them, but it should be done in a proper manner. This means this should be discussed with the team first on why they think they are able to take up more tasks and if that discussion is positive then arrive at a consensus on the revised upwards value of WIP limit. That limit should be approved by the project manager, product owner, and sponsors. Then it should be implemented.
Lean focuses on reducing waste to almost zero. This is where Kanban comes into the picture with its visualization focus. With the focus on limiting work in progress items, visualizing the work pipeline to bring focus on velocity, KPIs etc. it helps reduce waste and hence it is an important factor in Lean.
Kanban has the power to transform the focus of the team. First and foremost, the work items are arranged in the order of priority. This ensures ad-hoc work item assignment is reduced and hence, productivity and quality are maintained by reducing context switching.
Lean understands that going out of the way to deliver work items are often appreciated by higher management, but it is not sustainable. So, such practices are discouraged.
Instead, a work in progress limit is enforced so that team does not commit more than the capacity and does not pick up additional work items based on personal requests.
Any new work will need to be prioritized keeping in mind the existing work in progress.
A lot of time is wasted in the processing pipeline due to hand-offs or waiting for the right resources or allocation. This adds to the overall processing time.
So, value stream mapping concept requires you to create a visual flow of order from a customer at initiation stage to final delivery through all stages.
It could be requirement gathering, sign-offs, reviews, testing, development, etc. anything that is required to deliver the product to the customer is mentioned in sequence, along with wait times, processing times.
Finally, the authorities review the entire value map and identify areas where the most impact is occurring. This has led to the improvement of processing times across industries such as manufacturing, HR etc. This concept was first used by Toyota.
Visualization is the right answer because value stream mapping relies on creating a diagrammatic representation of the entire processing line from start to finish with wait times, lead times, processing times and aims at reducing the wastage.
Heijunka board is the answer. Heijunka board, unlike a simple scrum design board, allows all staffs to work independently. This reduces redundancy among the team, and the team does not have to wait for another person to finish their task.
Yes, it is possible through an open source solution known JimFlow, and it can interact with Trac Tickets. There are few benefits of it like:
Even though, both Lean and Six Sigma focus on waste reduction and improving efficiency, they key difference lies in the fact that Six Sigma is more inclined towards reducing the wastage margin towards 99.9999% whereas Lean is focused on setting up the right processes, the efficient pipeline, the culture and mindset of waste reduction.
So overall, it can be said that once we have matured Lean production in the organization then Six Sigma can be put on top of it.
5-S is one of the tools of implementing Lean in the project or organization. It organizes the work in the following manner:
Open Kanban can be considered as a movement based on the principles of Kanban and Agile to bring people from different backgrounds, domains, certifications together in a coherent manner. Because even though, people might come from manufacturing, construction, software etc. and they might have different certifications for their skills. But in the end, their goal is the same.
So Open Kanban comes into the picture wherever open source is involved.
So open Kanban is based on the freedom to change, adopt, modify as per need. And simplicity, where you just as much as you need and put it any shape as you want.
For example, in Open Kanban, the WIP [work in progress] is known as Reduce Base. That is, reduce the batch size of operations.
The systems can be of 2 types. Push systems or Pull systems.
Push systems mean we the owners, keep pushing work into the pipeline as much as possible with the hope that it would get processed and it would lead to maximum utilization. Whereas in Pull system, we design the system in such a way that it pulls the material from outside as and when the bandwidth frees up. So, velocity or efficiency is consistent.
Pull-based systems are a kind of JIT [Just in time environments].
Queuing theory and flow concepts align with it in the manner, that in order to have efficient operations with good velocity and if you are trusting the system to pull the material as needed then the entire flow in the pipeline needs to be smooth and uniform. And flow can be uniform if it adheres to querying theory that essentially says that only enough work should be queued for each node that can be processed without creating bottlenecks.
So, this way, these three concepts build WIP [Work in progress] limit concepts of Kanban.
Essentially, the implications of Little’s law are that we can reduce the wait time by improving the processing time and by controlling the queue length.
For example: if our capacity is of managing 4 requests per minute but we have an inflow of 8 requests per minute then obviously we have a wait time of 1 minute for first 4 items in the queue. So this is going to lead to a bottleneck and add to the queue.
But if we improve our processing to 8 requests per minute, there will be no bottleneck.
To achieve this, either we make an investment in better processors or capacity or find ways to improve the WIP limit through efficiency improvement techniques such as Value stream mapping.
Blocker clustering is a technique to group the blockers into clusters on the graph then analyze them. The graph lists down all the reasons on X axis and Y axis is the impact.
Using this data, the blockers and blockages are denoted by a DOT on the chart then we are able to understand the reasons that are primary reasons for blockers in the order of intensity. So, it makes sense to solve them first. This is blocker clustering.
Cumulative flow diagram is a graphical representation of flow in the system over a period. The red color shows the amount of work that is not yet started, green shows delivered and yellow shows in progress.
Over a period, red should constantly decrease and green should constantly increase with yellow being steady until the end.
CFD diagram shows the flow in the system over a period. So, if, at a time, there no increase in green but red is not decreasing either and at the same time, yellow is constant or increasing then it means. The pipeline is stuck because it shows processing is full, but requests are not getting completed.
Little’s law states that the average number of work items in a stable environment is equal to their average completion rate multiplied by their average time in the system.
The benefits of Scrumban are:
It is very important to differentiate the developers about the test case that is failed and returned and the test case that is ready or fresh to test. To differentiate this to the developer, you can split READY option in Kanban into two categories a) Re-open b) Ready. Re-open option status will have test-cases that are failed while ready option should have a new test case that is yet to be tested.
In Kanban, Power-ups allows you to customize your board as per your need. It adds various spectrum of features to your Kanban board like-
It applies to Optimize principle of Lean by creating value streams and hence finding ways to cut down on wastage occurring in the entire pipeline.
Time Tracker provides a detailed summary of the work done at that instant of time. It is useful in many ways like:
To link card together in Kanban, there are two ways: