Day in the Life of a Google Wallet Tech Lead

Key Concepts:

• Google Wallet development process
• Product Requirements Document (PRD)
• Engineering Design Document
• Code review process (Changelists)
• Testing (QA, Googler testing)
• Release process
• Rollback strategy
• Architecture decisions
• Burnout management
• Google's hiring process
• Delegation and Mentoring

1. Introduction and Guest Speaker

• Edson Yanaga hosts the Google Wallet live stream from Cary, North Carolina.
• This is the only live stream in May due to Google I/O later in the month, where Google Wallet will have a session to announce new features.
• Gokmen Goksel, a Tech Lead (TL) in the passes team for Google Wallet, is the guest speaker, streaming from East Bay, California.

2. Gokmen's Background and Role

• Gokmen is a computer engineer who joined Google in 2018 and has been with the same team since.
• He works in the passes team, which focuses on features like loyalty cards, event tickets, boarding passes, transit cards, gift cards, health insurance cards, and COVID cards.
• He has 20 years of experience, starting with hardware and transitioning to software.
• He previously worked on open-source projects.
• The passes team provides APIs for issuers to integrate with Google Wallet.

3. Feature Development Process

• The process starts with an idea or requirement from product managers or engineers.
• Product managers create a Product Requirements Document (PRD) detailing the feature's expectations, conditions, and use cases.
• The TL works with the product team to assess technical feasibility and timelines.
• The PRD goes through an approval process involving the team and related teams.
• A lead engineer creates an Engineering Design Document explaining how the feature will be implemented, potential changes to the stack, and alternative solutions with pros and cons.
• The Engineering Design Document includes context, options, pros and cons, and a schedule.
• The Engineering Design Document also undergoes an approval process.
• Implementation involves code changes (changelists) similar to GitHub pull requests.
• Metrics are provided to assess the feature's performance.
• Alerts are set up to monitor for issues.

4. Feature Development Timeline

• The timeline depends on the scope and location of the changes (API vs. application).
• UI changes in a specific area (e.g., gift cards) can take about a month.
• A new vertical like COVID cards took six months from idea to launch.
• The process is slower than in startups due to the need for precision and high quality for a large user base.

5. Time Allocation in Development

• Planning takes about 30% of the time.
• Development takes about 60% of the time.
• Testing takes about 10% of the time.

6. Testing Procedures

• Google has a QA testing team that tests products before release.
• Google also uses Googlers (internal employees) for testing and feedback.
• QA ensures accessibility standards are met.

7. Google Wallet Updates

• Google Wallet receives frequent updates.
• Updates are announced on the Google Developers blog and in live streams.
• Major updates are coming at Google I/O.

8. Optimization vs. Functionality

• If a feature is frequently used, optimization is prioritized.
• Part of the functionality is also performant.
• For less frequently used features, functionality may be prioritized first, with optimization as a follow-up.
• Resource usage (fonts, CPU, battery) is a key consideration.
• Postmortems (non-blame) are written when things go wrong to learn from mistakes.

9. Joining Google

• Check the career page (career.google.com) for roles and requirements.
• Apply with a CV.
• Recruiters will contact potential candidates.
• The interview process may include phone screenings and in-person or GVC interviews.
• Interviews may cover programming, system design, and behavioral aspects.
• Mock interviews are available.
• The book "Software Engineer at Google" (Red Flamingo Book) is recommended for understanding Google's engineering practices.
• Interviews are generic and not specific to the applied role.
• Candidates can use any language they are comfortable with.
• Knowledge of data structures and algorithms is essential.

10. Architecture Decisions

• Architecture decisions are driven by the expected outcome and product definition.
• The architecture should be reusable for similar implementations.
• The architecture should minimize refactoring in different places.
• Stakeholders need to agree on the architecture.
• The architecture should be scalable to support a large user base.
• The architecture should align with Google standards and internal tools.

11. Proudest Project

• Gokmen is most proud of the COVID cards project due to the tight timeline, user needs, and positive impact.
• He also mentions the Wear OS passes implementation, particularly the QR code rendering and scanning solution.

12. Personal Achievements

• Gokmen shares a story of using Google Wallet exclusively (loyalty card, tap to pay, transit card, event ticket) on his watch for an entire day.

13. Horror Story

• Gokmen recalls a time when a change he made could have affected millions of devices, but he was able to revert it in time.

14. Dealing with Burnout

• Gokmen follows the Inbox Zero principle.
• He handles tasks that take 2-3 minutes immediately.
• He uses the Postpone feature in Gmail to group related tasks.
• He avoids context switching.
• He uses the divide and conquer principle for large projects.
• He delegates tasks to mentor others.

15. Career Growth at Google

• Engineers can grow in their careers without becoming TLs or managers.
• It's better to be open to different technologies and contexts.
• Google values engineers who can add more value as engineers than as managers.

16. Handling Real-Time Issues

• Precautions are taken for new features to ensure easy rollback.
• Rollback strategies are documented in the Engineering Design Document.
• On-call personnel monitor for issues and can revert changes based on the documented strategy.

17. Conclusion

• The live stream provided insights into Google Wallet's development process, engineering culture, and career opportunities.
• Gokmen's experiences and advice offered valuable perspectives for aspiring and current software engineers.