Perfection in any craft comes from long hours of practice, and exploration of
the solution space. Programming is both an art and a science. We learn the
theory in college and by reading books, but to enhance programming skills to the
level of mastery we need to practice.
“But in the software industry we take developers trained in the
theory and throw them straight in to the deep-end, working on a project. It’s
like taking a group of fit kids and telling them that they have four quarters to
beat the Redskins (hey, we manage by objectives, right?). In software we do our
practicing on the job, and that’s why we make mistakes on the job. We need to
find ways of splitting the practice from the profession. We need practice
sessions. “ - Dave Thomas
A coding dojo is an exercise that brings the element of practice to programming.
It is usually conducted for a group of 8 – 16 people in a room with computer and
a projector. Participants are welcome to bring their laptops during the session,
if they wish to. In each session the participants work on a specific problem
statement and make it the base for their learnings. Each session starts with the
coach explaining the problem, followed by a quick design discussion. Once
everyone has understood the requirements and the design, the first pair comes at
the front and starts programming. The rest of the developers act as a
participative audience. They watch the solution unfold on the projector screen
and also point alternate paths, mistakes, or suggestions to the coding pair.
Each pair programs for 20 minutes in a round robin manner.
The coach acts as a facilitator, pointing out mistakes, better programming
approaches and also utilizes opportunities to transfer technical knowledge. For
instance, if the participants are writing IO related code, the coach may talk
about the difference in InputStream and Reader hierarchies in Java, and why they
use the decorator design pattern. Learning happens informally but very
effectively because explanations are within the context of code. The final ½
hour is reserved for discussing the main learning. Dojo's can also be conducted
with a specific goal – like refactoring to design patterns.
Duration and benefits:
Dojo sessions can be of a duration of 4 – 6 hours depending on the number of
participants and the problem statement. After each session the participants will
• Improved programming skills
• Improved design skills
• Understood approaches to problem solving and the implications of various
• Gained an enhanced understanding of the technology and API's used while
solving the problem.
• Computer, projector, language runtime and editor (JDK 1.4+ and
Frequently Asked Questions About Coding Dojo's
Q1. What is a coding dojo?
A1. A dojo is a exercise that brings the element of practice to programming. It
lets developers explore various solutions and approaches to a problem without
time pressures. Just like musicians and sportsmen practice to improve their
skills, these exercises help raise the bar of a programmer's skills.
Q2. How is a dojo conducted?
A2. The dojo begins with the facilitator/coach explaining the problem statement
to the group, followed with a quick design discussion. Once everyone has
understood the problem, the first pair starts programming while the others watch
on the projector screen. The audience should be a participative audience and not
a passive one. They should point out alternate solution paths and mistakes.
Everyone should contribute their knowledge. After 20 minutes the first pair
returns to the audience and the next pair continues programming from where they
left of... and so on. It is the responsibility of the programming pair to ensure
that everyone in the audience understands what they are doing. If someone has a
doubt, they can stop the pair and request them to clarify what they are doing.
While the participants solve the problem, the coach continuously transfers
relevant knowledge to the team by way of suggestions and inputs on the
underlying technology and API.
Q3. Are there other learning opportunities for the participants besides "raising
the bar of programming skills"?
A3. A lot of "technology learning" can also happen as a side effect. When I
conduct dojos for clients, I take every opportunity to transfer technology
specific knowledge every time an opportunity arises. For example, once we needed
to use some IO classes, and I spoke to the group about the IO and Reader
hierarchies and about the Decorator design pattern. Another time we needed to
implement a callback, and I took the opportunity and explained anonymous inner
classes and callbacks. Several learning opportunities will arise, but they will
usually depend on the the context of each exercise.
Q4. What kind of equipment do we need to conduct a dojo?
A4. A computer loaded with necessary software and a projector.
Q5. What software needs to be loaded on the computer?
A5. Assuming you will be working in Java: JDK(1.4+ is a good idea), an IDE
(Eclipse, NetBeans...), JavaDocs for the JDK classes, and any other tools,
libraries that are specific to the exercise. If the dojo is being done for a
language other than Java, you will need appropriate infrastructure for that
language. The infrastructure may include the language runtime, an IDE and any
other software that is necessary.
Q6. How many participants can attend a dojo?
A6. Between 4 - 16. Try not to exceed 16.
Q7. How long is a typical coding dojo?
A7. It depends on the exercise. In my opinion, for ant meaningful learning to
happen you need about 4 - 6 hours.
Q8. Can I take a large exercise and break it into multiple dojo sessions.
A8. Well, it can be done, but I will not recommend it, because participants may
have to spend time remembering what they did in the last session. The context
switch hampers efficiency in most cases.
Q9. Can a dojo be conducted without a coach/facilitator?
A9. Yes, but that will work well only with a group of experienced developers.
Q10. What are the skill levels needed to participate in a dojo?
A10. Fresh developers to very experienced programmers can all benefit from a
dojo. Software development is an art which always has scope for improvement.
However I will suggest that participants should have academic exposure to the
programming language in which the dojo will be
Q11. What kind of a mix of people (from a skills perspective) is best for an
A11. Having a group of similarly skilled people usually works out better. Even
though this can be subjective, a good guideline is to group people with the
following experience ranges together: 6 months - 12 months, 12 months - 36
months, 36+ months. Again, this is very subjective, and your mileage may vary.
Q12. Can dojos be used to explore refactorings?
A12. Yes, infact they can be used very effectively to understand refactoring
principles. In this case the dojo starts with smelly code that needs
refactoring, and the exercise is to refactor the code while discussing pros and
cons of each refactoring.
Q13. Can dojos be used for anything else?
Q13. Dojos can be used as a learning tool to understand any concept that needs
hands-on practice and an exchange of ideas. Design patterns, test first
development, pair programming, specific API's and probably many other skills can
be learned very effectively with dojos.
Q14. Are there any links to resources and example exercises?
A14. You must check out Dave Thomas' excellent page.
Q15. Do you conduct dojos?
A15. Yes I do. I conduct open as well as inhouse dojos in Pune, India. If you
are located elsewhere, I may be able to conduct it in your city. However if I am
unable to make it, I will be glad to share my experiences and help you conduct
the dojos yourself. You can mail me at - info (at) adaptivesoftware (dot) biz
Q16. What kind of benefits are experienced by participants in a dojo?
A16. Each dojo has certain learning objectives. After almost all dojos,
participants will have improved their programming and design skills. They will
understand good programming practices, like when and how to throw and catch
exceptions, how to create log files, good naming convention. They will also
learn the importance of loose coupling, high cohesion, pros and cons of
inheritance and composition, and other design best practices. They will learn
all these in a practical hands on manner, which is known to facilitate deep
learning. Besides these benefits each dojo presents unique learning
opportunities depending on the exercise. These opportunities can range from
better understand Java class libraries like to IO. collections library to
understanding design patterns, and language features.
Q17. Are Dojo's to be done as independent sessions or in a series?
A17. Dojos are always done as independent sessions. Each dojo is a unique
problem which must be completed on that day itself. In very rare (customized)
cases a dojo may extend beyond a day because the problem is large. In such cases
it is best to have the next dojo within 1 week or less. A dojo should ideally be
one day long, and at most two days long. It should not exceed two days, since
participants might lose the flow of programming. This might also result in time
being wasted in bringing participants up to date in what was done in the
Q18. What kind of preparation do the participants have to do before attending
A18. Participants should be familiar with Java, the IDE (Eclipse, Netbeans...)
that will be used, and object oriented principles. If the dojo is for another
language, then the participants will have to familiar with that technology.
Q19. Can it be used to run competitions and identify the best programmers ?
A19. Since a dojo is a cooperative process, it will be difficult to run
competitions to identify the best programmer within a team. However we may have
competing teams (of 4 people).
Q20. Can it be used to find gaps in programming skills of participants ?
A21. Yes, when the participants are programming during the dojo, the gaps in the
participants programming skills usually do become apparent. However again
since this is a group activity and is focused towards development of programming
skills, it should be used to help participants improve
their programming skills rather than for judging them.
The following diagrams illustrate possible room arrangement for conducting dojo
Fig 1: Arrangement for a conference
Fig 2: Arrangement for a classroom
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the source to Adaptive Software Solutions.