
Nikita Kraev
Verified Expert in Engineering
Mobile Developer
Amsterdam, Netherlands
Toptal member since August 25, 2020
Nikita is a skilled software engineer based in Amsterdam. His expertise spans various technologies from mobile (Kotlin, Android, React Native, and Flutter) to server-side, leveraging Scala and PHP/Hack. He can also lead through mentoring, optimizing codebases, and enhancing user experiences across different projects. With a bachelor's in computer science and a commitment to continuous improvement, Nikita is certainly a valuable asset to any tech team.
Portfolio
Experience
- Android - 10 years
- Kotlin - 10 years
- Firebase - 7 years
- React Native - 5 years
- GraphQL - 5 years
- RxJava 2 - 4 years
- Flutter - 3 years
- Coroutines - 2 years
Availability
Preferred Environment
Android Studio, Visual Studio Code (VS Code)
The most amazing...
...work I've done that felt like magic was the Meta View smart gallery. It uses an AI-powered assistant to suggest photos and make auto-montages.
Work Experience
Software Engineer
Hopper
- Implemented a customer experience refund flow using server-side rendering and custom framework, resulting in 90% satisfaction rate for flights cancelation flow.
- Built a ChatGPT-powered customer assistant that deep links into various surfaces in the app, reducing customer support reachouts by 62%.
- Leveraged a microservices architecture to remove price conversion from GRPC request payload, resulting in 150 msec/12% improvement in the booking flows.
Software Engineer
Meta
- Mentored three engineers on two different projects, enabling them to deliver their first features in less than three months after joining the team.
- Improved the ad campaign editing flow, resulting in a 90% faster experience, from 1.5 sec to 150 msec per editing attempt.
- Interviewed more than 50 candidates, resulting in three hires to the team.
- Facilitated a breakdown of the machine learning smart gallery prototype into achievable, concrete milestones.
- Reduced new feature implementation times and code duplication for internal developers by unifying the gallery rendering pipeline and making it reusable.
- Built support for multi-device viewing and implemented Ray-Ban Stories smart glasses media cropping and compression to make images shareable on Instagram and Facebook.
- Leveled up developers in the team by holding Kotlin best practices workshops and presentations.
Senior Android Developer
Voi Technology AB
- Migrated the legacy codebase into modern and coroutine-based reactive Kotlin code. The project took three months to develop but in the end, it allowed us to iterate 2.4x times faster than before (about 3.1W vs 7.66W before per feature).
- Developed a new Mapbox-based map layer, which rendered independently from server responses and improved our TTI (time to interact) by more than 350 milliseconds.
- Researched instruments and options and picked Flutter when creating a new employee application. That allowed me to iterate faster while being alone, compared to two other developers who worked together on the same project.
- Improved Agile processes in the team, resulting in a reduction of unnecessary meetings, better product owner awareness of progress, and new tool enablement for project scope visibility.
- Helped iOS engineers set up continuous integration and continuous delivery using CircleCI.
Android Developer
Rebtel Networks AB
- Led a development team of three Android engineers when creating a brand-new fintech banking app from scratch in very strict deadlines.
- Introduced Kotlin to the codebase by writing about 400 tests following the language's best practices and showcased them to the team.
- Created a feature toggle mechanism from scratch, bundling it into a legacy app that allowed us to remove dead code and cancel experiments 7x faster (3D vs 3W before).
- Led Material Design discussions with the lead designer which helped us to build a visually stunning custom application while keeping the native Android UX.
Lead Android Developer
Urbest
- Migrated an old and slow legacy Java app into Kotlin, reducing the lines of code (LOC) from 58,000 to just 19,000.
- Introduced dynamic module loading into native Android by splitting DEX files and ordering them by the module requirements. That improved our TTI (time to interact) by more than 1,300 milliseconds.
- Initiated the research and A/B testing on a small number of users to drive UX and UI discussions by metrics without being subjective.
- Participated in the launch of a React Native app rewrite (ClojureScript and React Native) while maintaining, extending, and bug-fixing a Kotlin version in parallel.
Experience
Voi Scooters App
https://play.google.com/store/apps/details?id=io.voiapp.voi&hl=en&gl=US&pli=1Majority
https://www.majority.com/en/Meta Ads Manager
https://play.google.com/store/apps/details?id=com.facebook.adsmanager&hl=en&gl=USI was one of the lead developers, doing the redesign of the app and bringing new and shiny features, including using the internal company framework for faster ad editing.
Meta View app
https://play.google.com/store/apps/details?id=com.facebook.stella&hl=en&gl=USI was in charge of designing and implementing the multi-device faceted architecture, bringing all my experience for ultra-fast scrolling and smooth transitions when downloading and viewing media.
Hopper app
https://play.google.com/store/apps/details?id=com.hopper.mountainview.play&hl=en&gl=USOne of the biggest achievements here is building a ChatGPT-powered smart travel assistant using SSR and a minimum amount of native code that allows you to book travel on the app.
Education
Bachelor's Degree in Computer Science
Innopolis University - Innopolis, Russia
Skills
Libraries/APIs
RxJava 2, Protobuf
Tools
Flow, Android Studio, IntelliJ IDEA, CircleCI
Languages
Kotlin, GraphQL, JavaScript, TypeScript, Clojure, Scala
Frameworks
React Native, Flutter, Dagger 2, ClojureScript, gRPC, Redux
Platforms
Android, Firebase, Visual Studio Code (VS Code), Linux, Mapbox, MacOS
Storage
RoomDB
Paradigms
Dependency Injection, Model View ViewModel (MVVM)
Other
Coroutines, Code Architecture, Reactive Streams, Material Design, Server-side Rendering (SSR), Architecture
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