Open to senior Android / KMP roles

KirillBorichevskiy

I build mobile systems, not just screens.

Android · Kotlin Multiplatform · Product Engineering. Android engineer with 6+ years shipping production apps used by millions — from solo ownership to KMP team leadership.

6+ years in mobile development
From solo ownership to KMP team leadership
Products used by millions of people

Explore my work Download résumé

years shipping mobile

10M+

installs on flagship apps

75M+

MAU on super-app work

Android UI

02 — Selected Work

Engineering case studies

Not screens — decisions. Each study follows the same path: context, the problem, the decision I made, and the measurable result.

01Grocery delivery · 10M+ installs

Faster home screen

Instacart

Context: Instacart's flagship consumer app serves millions of shoppers across the US and Canada. The home screen aggregates personalized storefronts, promotions and product discovery in a single GraphQL surface.
Problem: The home screen fired several large, deeply-nested GraphQL queries on cold start. P95 load time sat at 8.5s, discovery felt sluggish, and add-to-cart conversion suffered on slower networks.
Decision: I restructured the GraphQL queries into smaller, parallelizable fragments, introduced a product cache for discovery flows, and deferred non-critical sections so the fold rendered first.

8.5s → 3.9s

Home P95 load

+24%

Add-to-cart conversion

−16%

Support tickets (delivery)

KotlinJetpack ComposeApollo GraphQLCoroutinesStripe

02Super-app · 75M+ MAU

Messaging & media platform

Zalo

Context: Zalo is Vietnam's leading messaging and super-app. I worked across chat, media, short-form video and platform modernization while the codebase and team scaled rapidly.
Problem: A growing monolith slowed builds to a crawl, chat media loading stuttered on mid-range devices, and legacy MVP + RxJava code made the messaging layer hard to evolve safely.
Decision: I split the monolith into feature modules with a clean DI graph, migrated chat to MVVM + Coroutines/Flow, and rebuilt media loading around a native C++ BlurHash decode pipeline with progressive preview rendering.

~3× faster

Build time

−30%

Media preview P95

−11%

Janky frames

KotlinC++Media3CoroutinesModularization

03Telematics SDK · 60+ partners

Mobility & telematics

DriveQuant

Context: DriveQuant builds driving-behavior telematics. I was the solo Android developer on a white-label DriveKit app for French drivers and contributed to the DriveKit SDK reused across 60+ partners.
Problem: Trips were missed or started late, GPS drained the battery, and drivers on poor connectivity lost recorded trips entirely — unacceptable for an insurance-grade telematics product.
Decision: I gated GPS behind low-power motion, activity, geozone and BLE-beacon signals to confirm trip intent, and added offline-first trip recording with retry-based synchronization once connectivity returned.

84% → 92%

Trip detection accuracy

−8%

Battery impact

98%

Recovered failed uploads

KotlinMVVMBLEGoogle Maps SDKPlay Billing

03 — Performance Lab

Numbers I moved

A profiler's view of the wins I'm proudest of. Every metric started as a measurement — expand any card to see how it moved.

Build time

~3× faster

3×faster

Home screen P95

8.5s → 3.9s

before

8.5s

after

3.9s

improvement

Media preview P95

−30%

before

100%

after

70%

improvement

Trip detection

84% → 92%

Add-to-cart

+24%

+0%

04 — Career

Where I've made an impact

Six years of shipping production mobile products — from solo ownership to KMP team leadership across grocery, super-apps and telematics.

KMP Engineer

Kotlin MultiplatformApr 2025 – Present

Instacart

Shared foundations across Android and iOS in a flagship 10M+ install app.

Built a KMP design system from scratch (~40 reusable components) for Android and iOS
Shipped on-demand device log export via a shared module (+38% support incidents closed per sprint)
Cross-platform architecture, shared business logic and automated publishing

Senior Android Engineer

Large-scale Android productsOct 2021 – Apr 2024

Zalo

Messaging, media and platform work on a super-app with 75M+ MAU.

Built Stories: DAU 300K → 2M, WAU 1.5M → 6M as rollout expanded
Delivered the Kiki Info AI assistant Android experience — 1M+ visits in under two months
Modularized the monolith (~3× faster builds), migrated to Coroutines/Flow
Introduced unit testing: ~80% line coverage on feature logic, regression inflow −15%

Android Engineer

Solo Android ownershipJan 2020 – Oct 2021

DriveQuant

A white-label telematics app built from scratch, reused across 60+ partners.

Owned the app end-to-end: architecture, BLE, telematics, maps and releases
Offline-first trip recording recovered 98% of temporarily failed uploads
Trip detection 84% → 92%; battery impact −8% through smart GPS gating
Google Play Billing / In-App Review / Updates — 96% purchase success, rating +0.6

Full résumé (PDF)

05 — About & Stack

The mobile engineering map

A T-shaped toolkit grouped by what it actually does in a product — from the pixels users touch to the pipelines that ship them.

Android engineer with six years of commercial experience — from projects where I owned Android development end-to-end to teams of ~40 people, remotely and on-site. In my latest role I worked as a KMP Engineer. I own the full development cycle: from clarifying and shaping requirements through multi-module architecture, automated releases, and production monitoring. Almost every engagement was in a new domain for me: grocery delivery, telematics, super-apps — so ramping up quickly in unfamiliar areas became a skill in its own right. I believe in a T-shaped engineering path: beyond core Android I've worked on design systems, media-heavy flows, SDK development and integration, and CI/CD pipelines built from scratch. In my spare time I study backend development, write and deploy Ktor microservices, and explore AI-assisted tooling. I also teach Android at my university and build an open-source educational platform for mobile development.

EducationBelarusian State University— MSc, Software Engineering of High-Load Mobile Systems2018 – 2024