Senior iOS Engineer - Performance, Stability and Monitoring

Dream big
- Be visionary, strategic, and open to innovation
Build great things
- Work in service of our users, always improving and pushing higher
Operate like an owner
- Take responsibility with bold decision-making and bias for action
Win like a sports team
- Be trusting and collaborative while empowering others
Learn and grow fast
- Never stop learning and iterate fast
Share our passion
- Share ideas and practice enthusiasm and joy
Be user obsessed
- Empathetic, inquisitive, practical

The Apple Performance, Stability and Monitoring (PSM) team sits within Foundation. At Goodnotes, our Foundation teams ensure that the app experience is seamless, responsive, and resilient, no matter how complex the product becomes. As a Senior iOS Engineer in the Apple PSM team, you will tackle challenges across performance optimisation, memory management, concurrency, alerting and monitoring, among others.
Goodnotes is an offline-first app, and most of the features you see run locally on the device. That presents a lot of challenges to ensure they can run smoothly, even on high-end devices. In the Apple PSM team, you’ll collaborate with other teams to understand the challenges in the code they produce and promote best practices that maximise performance and stability. Stability and performance are one of our top user concerns. Join us to make Goodnotes fast and reliable, and make a true impact on millions of users.
You'll be:

• Having performance and stability, and the center of everything you to to help addressing some of the top user concerns about performance and stability
• Implementing best practices for automated tests
• Creating custom monitors that allow teams to quickly realise if users are having a suboptimal experience with the code they shipped
• Continuously improve the development practices through research, automation, documentation and testing
• Share your knowledge and experience with the rest of the team

You'll need:

• Expertise in Swift programming. Experience with Swift Concurrency is a plus
• True care about performance and appreciate that even minimal performance gains matter
• A strong understanding of computer science fundamentals and an enjoyment of solving algo and data structure puzzles.
• Excellent problem solving, communication, and storytelling skills
• Strong sense of the best tools for any task
• High sense of autonomy
• Good analytical skills, investigating performance issues using Instruments or other tooling.
• Proven experience working on sizable and complex codebases

Big plus if:

• You have worked with apps with millions of MAUs, and you understand the cost implications and problems large user bases may have
• You have experience building custom tooling to identify / analyze perf issues
• You have experience cross-compiling codebase on different mobile platforms

Even if you don’t meet all the criteria listed above, we would still love to hear from you! Goodnotes places a lot of value on learning and development and will support your growth if needed.
The stack:

• Programming Language: The vast majority of our code is written in Swift
• CI / CD: We use CircleCI although we’re slowly migrating to TeamCity. We also have an in-house CI system on top of TeamCity / CircleCI to selectively test what's needed based on the changes on a PR
• Cloud Monitoring: DataDog
• Concurrency: We have a large, old, but modular codebase. We use modern Swift Concurrency as much as possible as we gradually move away from RxSwift
• UI code: As much new UI code as possible is in SwiftUI. We fall back to UIKit when needed and re-use the majority of it on macOS using Catalyst
• Cross-platform: We re-use our core packages on cross-platform using SwiftWasm, UI for other platforms is written using React or their respective native APIs
• Dependencies: We exclusively use Swift Package Manager and frequently make new local packages
• Source control and builds: We have a mono-repo and use GitHub and Pull Requests. We have an internal tool to manage build generation that also powers our semi-automatic, soon-to-be fully automatic, release process.
• Release cadence: We QA and release on a weekly schedule

The interview process:

• Introduction: The Talent Team want to hear more about your background, what you are looking for, and why you’d like to join Goodnotes.
• Technical Screening: A timed coding challenge on the Hackerrank platform.
• Onsite Live coding & Technical interview: A live coding call with one of our engineers. This is where you get to see what it would be like working at Goodnotes as well as the chance to ask any engineering questions you may have
• AI literacy interview: A short conversation with an AI Champion on your understanding and use of AI tools
• Hiring Manager interview: A call with your hiring manager. This is the person who will be managing you day to day, working on your growth and development with you as well as support you throughout your career at Goodnotes.
• Values interview – Meeting with members of the Goodnotes Team to answer questions relating to take ownership AND build great things

Please note that technical interviews are held onsite in our office locations (London, Hong Kong & Singapore) all transport, accommodation and costs involved will be covered by the Goodnotes team.
What’s in it for you:

• Remote friendly
• Flexible working hours and location
• Medical insurance for you and your dependents
• Great annual leave allowance
• Meaningful equity in a profitable tech-startup
• Budget for things like noise cancelling headphones, setting up your home office, personal development, professional training, and health & wellness
• Sponsored visits to our Hong Kong or London office every 2 years
• Company wide annual offsite
• Fantastic maternity/ paternity packages and and allowances