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Below is my summary of “Practices of an Agile Developer: Working in the Real World” by Venkat Subramaniam and Andy Hunt. In my view this is a 4-star book, well worth reading in its entirety.
Aside from introductory and closing chapters, each chapter of the book describes one of 45 practices that are important in achieving an Agile development environment (one reviewer suggested it be renamed, “45 Habits of Highly Effective Developers”)
The thing I like most about the book is the emotional awareness of the authors. They recognise that development is as much an emotional experience as it is a technical one, and that communicating good practice needs to address the readers’ emotional needs as well as their practical ones. This applies to both the presentation and content of each chapter. As a result, I felt good about reading this book, and I feel good about trying out the espoused practices.
The language, typography and layout make it an easy read.
The subdivision of the book into 45 practices means that:
- It can be read in digestible chunks
- It is possible to dip-in
- It makes a good reference book
The chapters on each of the practices includes:
- A practice number and title, for easy reference.
- An explicit statement of the reasons why we might resist the practice described (the Devil’s temptation)
- A discussion that explains the rational behind the practice and how to apply it practically, typically backed up by real-world examples
- A summary of the key message of the chapter (the Angel’s advice)
- The emotional outcome of following the practices described (What it Feels Like). This encourages emotional buy-in.
- Notes on how not maintain perspective (“Keeping Your Balance”)
Work for Outcome (Page 12) – PoAD#P1
Prioritise finding the culprit over resolving the problem
- Reactive and defensive people are unproductive
- Assigning blame can make the situation worse
- It is rare that one person is entirely to blame
- Everyone makes mistakes (unless they take no risks)
- A person’s misunderstanding / ignorance/mistake often reveals an area for team development
Outcome is more important than taking credit / apportioning blame
Blame doesn’t fix bugs
Offer to help.
Be part of the solution, not part of the problem
Don’t argue about it, fix it.
- Safe to admit ignorance
- Mistakes are learning opportunities
- Remove bad apples from the bunch
- Remove yourself from a bad team
- Credit-whoring can be just as bad as apportioning blame
- Both the fear of and actuality of blame / credit whoring is damaging productivity
Quick Fixes Become Quicksand (Page 15) – PoAD#P2
Make a quick fix to code you don’t really understand
Clarity of code goes down
Accumulation of quick fixes become “quicksand”
You can’t possibly be agile with that kind of baggage
Long term code clarity is more important than short-term fixes.
- Get a good understanding of the overall architecture and design
- Understand the code you modify
- Avoid quick hacks
- Invest in code clarity
Fix the problem, not the symptom
- Don’t code in isolation (e.g. use code reviews)
- Unit testing
- Clean code
- No areas of untouchable code
- Developers have a general working knowledge of the code base
There are no dark corners in the project
- You don’t need to become an expert at everything
- Larger systems are rarely understood by one individual
- If the code can’t be understood by the team, it is too hard to maintain – even for the original author
Quick fixes can be bad news in the short term, too. The project was a static data loader that threw an exception. I made a small change to a piece of code I didn’t fully understand. The consequence was the the data in the wrong version of the database was overwritten.
Criticize Ideas, Not People (Page 18) – PoAD#P3
Making it about who is right rather than what is right.
- Does nothing to enhance understanding
- Suppresses innovation
- Makes people unhappy
- Everyone has bad ideas
- Nothing is perfect – there is only “better”
- Bad ideas can stimulate good ones
- Everyone starts somewhere
- Compromises are inevitable
Focus on the best solution, not the best person.
Criticize ideas, not people
- Ask open questions to reveal flaws and solutions
- Don’t be afraid of criticism
- When you see a potential problem, realistically ask how often a problem actually occurs
- Support the decision
Tools for Overcoming Indecision
- Set a deadline
- Argue for the opposite
- Freedom to explore ideas
- Ideas can be rejected without hurt feelings
- Imperfect ideas can be adopted without guilt
- Make sure everyone agrees on what “best” means. Users and developers often disagree
- Sometimes you have to accept the least worst solution
Damn the Torpedoes, Go Ahead (Page 23) – PoAD#P4
Ignore important issues to avoid uncomfortable situations
Courage to do what is right
- Be courageous
- Communicate truth
- Do the right thing
Admiral David Farragut:
Damn the torpedoes, full speed ahead!
- Short-term discomfort
- Relief, not dread
- Festering problems addressed
- If everyone else disagrees, you may be explaining it wrong – or just wrong
- Impatience is not courage – take time to understand why things are the way they are
Keep Up with Change (Page 28) – PoAD#P5
Keep up with changing technology. You don’t have to become an expert at everything, but stay aware of where
the industry is headed, and plan your career and projects accordingly.
Invest in Your Team (Page 31) – PoAD#P6
Raise the bar for you and your team. Use brown-bag sessions to increase everyone’s knowledge and skills and help bring people together. Get the team excited about technologies or techniques that will benefit your project.
Know When to Unlearn (Page 34) – PoAD#P7
Learn the new; unlearn the old. When learning a new technology, unlearn any old habits that might hold you back.
Question Until You Understand (Page 37) – PoAD#P8
Keep asking Why. Don’t just accept what you’re told at face value. Keep questioning until you understand the root of
Feel the Rhythm (Page 40) – PoAD#P9
Tackle tasks before they bunch up. It’s easier to tackle common recurring tasks when you maintain steady, repeatable intervals between events.
Delivering What Users Want
Let Customers Make Decisions (Page 45) – PoAD#P10
Let your customers decide. Developers, managers, or business analysts shouldn’t make business-critical decisions. Present details to business owners in a language they can understand, and let them make the decision.
Let Design Guide, Not Dictate (Page 48) – PoAD#P11
A good design is a map; let it evolve. Design points you in the right direction. It’s not the territory itself; it shouldn’t dictate the specific route. Don’t let the design (or the designer) hold you hostage.
Justify Technology Use (Page 52) – PoAD#P12
Choose technology based on need. Determine your needs first, and then evaluate the use of technologies for those specific problems. Ask critical questions about the use of any technology, and answer them genuinely.
Keep It Releasable (Page 55) – PoAD#P13
Keep your project releasable at all times. Ensure that the project is always compilable, runnable, tested, and ready to deploy at a moment’s notice.
Integrate Early, Integrate Often (Page 58) – PoAD#P14
Integrate early, integrate often. Code integration is a major source of risk. To mitigate that risk, start integration early and continue to do it regularly.
Automate Deployment Early (Page 61) – PoAD#P15
Deploy your application automatically from the start. Use that deployment to install the application on arbitrary machines with different configurations to test dependencies. QA should test the deployment as well as your application.
Get Frequent Feedback Using Demos (Page 64) – PoAD#P16
Develop in plain sight. Keep your application in sight (and in the customers’ mind) during development. Bring customers together and proactively seek their feedback using demos every week or two.
Use Short Iterations, Release in Increments (Page 69) – PoAD#P17
Develop in increments. Release your product with minimal, yet usable, chunks of functionality. Within the development of each increment, use an iterative cycle of one to four weeks or so.
Fixed Prices Are Broken Promises (Page 73) – PoAD#P18
Estimate based on real work. Let the team actually work on the current project, with the current client, to get realistic estimates. Give the client control over their features and budget.
Put Angels on Your Shoulders (Page 78) – PoAD#P19
Use automated unit tests. Good unit tests warn you about problems immediately. Don’t make any design or code changes without solid unit tests in place.
Use It Before You Build It (Page 82) – PoAD#P20
Use it before you build it. Use Test Driven Development as a design tool. It will lead you to a more pragmatic and simpler design.
Different Makes a Difference (Page 87) – PoAD#P21
Different makes a difference. Run unit tests on each supported platform and environment combination, using continuous integration tools. Actively find problems before they find you.
Automate Acceptance Testing (Page 90) – PoAD#P22
Create tests for core business logic. Have your customers verify these tests in isolation, and exercise them automatically as part of your general test runs.
Measure Real Progress (Page 93) – PoAD#P23
Measure how much work is left. Don’t kid yourself — or your team — with irrelevant metrics. Measure the backlog of work to do.
Listen to Users (Page 96) – PoAD#P24
Every complaint holds a truth. Find the truth, and fix the real problem.
Program Intently and Expressively (Page 100) – PoAD#P25
Write code to be clear, not clever. Express your intentions clearly to the reader of the code. Unreadable code isn’t clever.
Communicate in Code (Page 105) – PoAD#P26
Comment to communicate. Document code using wellchosen, meaningful names. Use comments to describe its purpose and constraints. Don’t use commenting as a substitute for good code.
Actively Evaluate Trade-Offs (Page 110) – PoAD#P27
Actively evaluate trade-offs. Consider performance, convenience, productivity, cost, and time to market. If performance is adequate, then focus on improving the other factors. Don’t complicate the design for the sake of perceived performance or elegance.
Code in Increments (Page 113) – PoAD#P28
Write code in short edit/build/test cycles. It’s better than coding for an extended period of time. You’ll create code that’s clearer, simpler, and easier to maintain.
Keep It Simple (Page 115) – PoAD#P29
Develop the simplest solution that works. Incorporate patterns, principles, and technology only if you have a compelling reason to use them.
Write Cohesive Code (Page 117) – PoAD#P30
Keep classes focused and components small. Avoid the temptation to build large classes or components or miscellaneous catchall classes.
Tell, Don’t Ask (Page 121) – PoAD#P31
Tell, don’t ask. Don’t take on another object’s or component’s job. Tell it what to do, and stick to your own job.
Substitute by Contract (Page 124) – PoAD#P32
Extend systems by substituting code. Add and enhance features by substituting classes that honor the interface contract. Delegation is almost always preferable to inheritance.
Keep a Solutions Log (Page 129) – PoAD#P33
Maintain a log of problems and their solutions. Part of fixing a problem is retaining details of the solution so you can find and apply it later.
Warnings Are Really Errors (Page 132) – PoAD#P34
Treat warnings as errors. Checking in code with warnings is just as bad as checking in code with errors or code that fails its tests. No checked-in code should produce any warnings from the build tools.
Attack Problems in Isolation (Page 136) – PoAD#P35
Attack problems in isolation. Separate a problem area from its surroundings when working on it, especially in a large application.
Report All Exceptions (Page 139) – PoAD#P36
Handle or propagate all exceptions. Don’t suppress them, even temporarily. Write your code with the expectation that things will fail.
Provide Useful Error Messages (Page 141) – PoAD#P37
Present useful error messages. Provide an easy way to find the details of errors. Present as much supporting detail as you can about a problem when it occurs, but don’t bury the user with it.
Schedule Regular Face Time (Page 148) – PoAD#P38
Use stand-up meetings. Stand-up meetings keep the team on the same page. Keep the meeting short, focused, and intense.
Architects Must Write Code (Page 152) – PoAD#P39
Good design evolves from active programmers. Real insight comes from active coding. Don’t use architects who don’t code—they can’t design without knowing the realities of your system.
Practice Collective Ownership (Page 155) – PoAD#P40
Emphasize collective ownership of code. Rotate developers across different modules and tasks in different areas of the system.
Be a Mentor (Page 157) – PoAD#P41
Be a mentor. There’s fun in sharing what you know—you gain as you give. You motivate others to achieve better results. You improve the overall competence of your team.
Allow People to Figure It Out (Page 160) – PoAD#P42
Give others a chance to solve problems. Point them in the right direction instead of handing them solutions. Everyone can learn something in the process.
Share Code Only When Ready (Page 162) – PoAD#P43
Share code only when ready. Never check in code that’s not ready for others. Deliberately checking in code that doesn’t compile or pass its unit tests should be considered
an act of criminal project negligence.
Review Code (Page 165) – PoAD#P44
Review all code. Code reviews are invaluable in improving the quality of the code and keeping the error rate low. If done correctly, reviews can be practical and effective. Review code after each task, using different developers.
Keep Others Informed (Page 168) – PoAD#P45
Focus on getting the job done. If people want a status update, they’ll ask.
- Trust diminishes
- You won’t get help
- Customers can’t re-prioritize
- Interruptions for status updates
Keep others informed
- Tell people, don’t wait for them to ask
- Deliver bad news early: don’t give people unpleasant surprises
- Publish designs, cool ideas, research, status etc.
Stay head’s up, not head down
- Sticky notes
- Phone calls
- Status charts
- Daily stand-up
- People don’t pester you for status updates
- Know your audience, level appropriately
- Don’t let communication efforts get in the way of work progress