What is a scrum process and how does it work?

To implement the scrum development process, it is important to know how it actually works. Most of the errors in the development occur because of the lack of knowledge about the working process of the scrum. 

Scrum works on the principle of iterative and incremental development and it operates with the help of two types of roles namely:

1. Core roles:

(i)                Scrum master

(ii)              Development team

(iii)            Product owner

2. Ancillary roles:

(i)                Stake holders and

(ii)              Managers

What is a scrum process?

- The scrum process deals in terms of sprints which are usually called iterations for the other agile software development processes. 

- In a typical scrum, a sprint may have duration of a week to a month. 

- Scrum is facilitated by various meetings which have been mentioned below:

1. Daily scrum: 

This meeting is held during the sprint and is based up on the project status. Usually the core roles participate in this meeting. This meeting is time boxed to 15 minutes.

2. Story time (back log grooming): 

This process involves the estimation of the existing backlog and the acceptance criteria for the user stories is also refined. These meetings are time boxed to an hour.

3. Scrum of scrums: 

This meeting follows after daily scrum and is somewhat same.

4. Sprint planning meeting: 

This meeting is held before the beginning of every sprint and the tasks that have to be completed within that sprint are selected.

5. Sprint review meeting: 

It reviews the status of the sprint and also the tasks that could not be completed.

Principles on which working of scrum depends

The scrum follows the following three principles throughout its working:

1. Working software is more valuable then the documentation.
2. Response to the changes in requirements is more important than the plan.
3. Team collaboration is important than contract negotiation.

How does a scrum process work?

- Usually the first few weeks of the scrum are spent working out the high level requirements including business needs and system architecture. 

- After this, the team produces the product backlog and sprint backlog. 

- These two backlogs together make the scope of the software project by the end of the week. - All the team member themselves take up the responsibilities and operational activities from each other during the daily meetings. 

- At the end of some sprints, it happens that some of the tasks could not be completed as planned so they have to be included in the next sprint in addition to the other tasks. 

- One of the reasons for such situations is the “scope creep”. 

- However, this does not turns out to be a real issue especially when the team is working closely with the business owners who have good understanding of the development process going on. 

- It should be understood that the scrum is a framework rather than just being a full methodology. 

- A detail of everything that is to be done is not provided by the client since it is decided by the team itself.

- At the end of the sprints the coding, testing, integration of the features is done. 

- In the sprint review, the newly added features to the software are demonstrated to the product owner. 

Reasons why scrum works well

There are several reasons why scrum works and few of them have been mentioned below:

1. Iterative nature.
2. Re assessment of priorities between iterations.
3. The old check points are discarded when the team is doing something new.
4. Availability of the product owner.
5. The development team works on a single project at a time.
6. The team has a chance to co- locate the entire development process.

Some detail about usage of work products in extreme programming?

Extreme programming or XP gained popularity as one of the most effective agile software development practices in the late nineteen’s. This methodology came in to existence for the purpose of the implementation of the software projects using the 12 predefined practices.

These practices are a refinement of the best practices of the software engineering. The whole process is intended in making improvements to the quality of the software system and its ability to respond to the needs of the customer. 

The frequent releases of the software system or application are regulated by the iterations or the short development cycles. There are certain elements of the extreme programming which include:

    1. Pair programming

    2. Extensive code reviews

    3. Unit testing of the whole code

    4. Avoiding programming of the features and functionalities that are not required at the moment.

    5. Keeping a flat maintenance structure.

    6. Maintaining clarity as well as the simplicity in the code.

    7. Expecting changes in the requirements of the customers.

The above mentioned elements make the whole development process all better. During Kent Beck’s work on his C3 (Chrysler comprehensive compensation system) pay roll project, he developed this agile software development methodology. 

Extreme is nothing but as the name suggests, a process of implementing the best practices of the software engineering to the highest levels possible. Extreme programming has always been surrounded by a lot of buzz regarding the environments in which it was used and is being used. 

Its practices always demands high discipline making them appear to be so rigid. On the other hand if an approach is quite flexible and less rigid, schedule makes it easy to incorporate complex features in to a fully developed software system or application. 

The practice continuously integrating the whole software system helps a big deal in keeping the whole development on the right track. With its 4 activities (namely coding, testing, listening and designing) the extreme programming is aimed at achieving the below mentioned goals:

1. Organize the people to produce software products with high quality and productivity.
2. Reduce the cost of the changes in the customers’ requirements with the multiple short development cycles.
3. Define changes as the natural and desirable aspect of the software projects.

About Work products in Extreme Programming

This article is focused up on the work products of the extreme programming. In one research it was found that the extreme programming helped in many of the projects in reducing the costs and time to market the software products and improved the productivity.  

- Describing the work products of a software methodology helps in checking out the problems of the interpretation.

- Extreme programming is not a small methodology therefore it involves a large number of intermediate work products. 

- But to say as a whole, the work products are quite necessary.

- People who are just beginning with the extreme programming need to know what are actually acceptable work products. 

- The stake holders need to know what they are entitled to ask for. 

- Three work products are mentioned that are typical to an extreme programming development process. 

- The number of the work products depends on how they are counted. 

- In the extreme programming the work products are distributed across the roles i.e., to say they are light. They are:

1. System architecture
2. Common domain model
3. Screen drafts

- There are dozens of the work products and doing each of them might be a hectic work! But on the other hand if you skip out many of them your project will lose its visibility as well as its alignment.

- You cannot pick some core work products since even lose of one product can hamper the whole project development. 

What are the core practices of extreme programming?

Over the time the extreme programming has proved itself to be a great helping hand as an agile practice in improving the overall quality and productivity of the software products according to the ever changing requirements of the customer.
Being an agile practice it frequently releases software products with the short development cycle which is achieved through time boxing. During the whole process several check points are introduced in to the development cycle where the new customer requirements can be easily incorporated in to the software system.

Elements of Extreme Programming

There are several elements of the extreme programming like:
1. Pair programming
2. Extensive code review
3. Unit testing
4. Maintain simplicity and clarity of the code
5. Providing a flat management structure and so on.

Values of Extreme Programming

The extreme programming is guided by values, rules and principles! There are 5 values namely:
1. Communication
2. Simplicity
3. Feedback
4. Courage
5. Respect

Principles of Extreme Programming

The rules of the extreme programming govern its all time activities. Three basic principles have been defined for the extreme programming as mentioned below:
1. Feedback
2. Assuming simplicity
3. Embracing change

core Practices of Extreme Programming

The extreme programming is said to be composed of 12 practices which is what we going to discuss in this article. The 12 practices have been grouped into sets of four:

1. Fine Scale Feedback: This area involves 4 following practices:
(a) Programming in pairs: This agile practice involves 2 programmers working side by side one of which is a driver and other is an observer. The driver is suppose to type in the code while the observer holds the duty to review each line of the code typed.

(b) Planning game: This is the most important practice in the extreme programming. The game here is the name given to a meeting that is held once for every iteration of the development process with the purpose of guiding the product in to delivery. It has 2 parts:
- Release planning: It has 3 phases:
    + Exploration phase
    + Commitment phase
    + Steering phase
- Iteration planning: It too has got the same phases as the release planning.

(c) Test driven development or TDD: This is another agile practice relying on the iterative and incremental approach and refactoring of the code for improving its overall design.

(d) Whole team: Extreme programming forces the need of the customer availability at all the times for questions.

2. Continuous Process: This process is constituted of the following 3 practices:

(a) Continuous integration: In extreme programming it is required that only the latest version of the software system or application is worked up on.  The current version of the software that is available with the different team members must be uploaded to the code repository in every few hours since this avoids delays in the project cycle.

(b) Design improvement or re-factoring of the code: Since only the required functionalities are implemented, this may cause the system to hang. This may require dual maintenance then. In such cases changes in one part of the program affect the other parts of the code. At such times the refactoring of the code is needed.

(c) Small releases: The software is delivered via the frequent releases of the live functionalities. With these small releases the customers gains the confident about the progress of the development and the concept of the “whole team” is also maintained. The customer as well is able to come up with the suggestions regarding the development of the software.

3. Shared Understanding: This involves the following 4 practices:
(a) Coding standards
(b) Collective code ownership
(c) System metaphor
(d) Simple design

4. Programmer Welfare: It involves development at a “sustainable pace”.