AbhishekContact
01 / Senior iOS Engineer

iOS THATSURVIVESTHE REAL WORLD.

[02]

I design and scale production-grade voice & video systems — WebRTC, CallKit, VoIP — built to survive cold starts, locked devices, and 3G. Currently shipping at YEO Messaging (UK).

— quote

Specialized in solving edge cases most engineers avoid.

See the WebRTC case studyMy apps on App StoreRésuméContact
Abhishek Suryavanashi — Senior iOS Engineer— abhishek · 2026
— credits
RoleSenior iOS Engineer
NicheReal-time Communications
StackSwift · WebRTC · CallKit · PushKit
StatusShipping at YEO Messaging (UK)
Years7+
/01
7+
Years shipping iOS in production
/02
Live
WebRTC voice & video — YEO Messaging
/03
1000s
Of users across production releases
Trusted in production at
/01
YEO Messaging
UK · Production WebRTC
/02
McDonald's Canada
High-traffic consumer iOS
/03
Boxing Warrior
Production iOS
/04
Capgemini
Enterprise consultant
●Live · 2026
Production · iOS

Real systems. Shipped to App Store.

A glimpse of the real surfaces — call UI, signaling code, lifecycle handling. Not renders. Not mockups. Production iOS.

CallController.swift
1// Production · YEO Messaging
2import WebRTC
3import CallKit
4 
5final class CallController: NSObject {
6let provider: CXProvider
7let factory = RTCPeerConnectionFactory()
8 
9func report(uuid: UUID, from caller: String) {
10let update = CXCallUpdate()
11update.remoteHandle = CXHandle(type: .generic, value: caller)
12provider.reportNewIncomingCall(with: uuid, update: update)
13}
14}
/01CallController.swift · production
9:41•••
● Connected · 02:14
YE
YEO Team
WebRTC · Audio + Video
/02YEO Call · WebRTC active
/03What I specialize in

Hard problems.Not surface UI.

— four areas where I've shipped production systems

The kind of work that decides whether a product actually works in the real world — not the demos, the production-grade reality of it.

  1. /01Specialization

    Real-time communication systems

    WebRTC, VoIP, signaling, ICE/TURN — production-grade voice & video on iOS.

  2. /02Specialization

    Complex iOS lifecycle handling

    Background, terminated, locked-state, FaceID gates, and cold-start recovery.

  3. /03Specialization

    Debugging production-level edge cases

    The bugs that don't show up in tutorials — race conditions, audio drops, ghost calls.

  4. /04Specialization

    Building scalable AI-powered applications

    LLM integration, prompt caching, streaming UX, and cost-aware routing.

/04Featured work

Real systems.Shipped to App Store.

— three case studies, one flagship + two products

A flagship real-time communication system used in production at YEO Messaging, and two AI-native iOS products. Every one has a hard engineering core, not just a UI.

Flagship project
01Flagship · Production
Production · UK
Thousands of users · Live in App Store

WebRTC Voice & Video — YEO Messaging (UK)

End-to-end real-time calling for a secure messaging platform: CallKit, PushKit, signaling, and multi-device sync.

Owned and shipped a production-grade WebRTC calling system for YEO Messaging — a secure, identity-verified communications app used across UK enterprise. Calls had to survive cold starts, locked devices, FaceID prompts, Bluetooth handoff, and unstable mobile networks.

CallKit + PushKit (VoIP)

Wake-on-VoIP with PushKit, native incoming UI through CallKit, deterministic lifecycle across foreground / background / terminated states.

Signaling — GraphQL + WebSocket

Resilient signaling layer with reconnect, ICE restart, and message ordering guarantees on flaky networks.

Multi-device call sync

Coordinated ringing, pickup, and hang-up across a user's logged-in iOS / web devices without ghost calls.

Audio routing — AVAudioSession

Bluetooth (HFP/A2DP), speaker, and receiver prioritization with route-change recovery and category negotiation.

Challenges solved
  • Audio failure in terminated state
    Diagnosed and fixed silent-audio class of bugs caused by AVAudioSession activation racing PushKit wake-up; hardened the activation sequence.
  • SDP race condition
    Eliminated an offer/answer interleaving bug under reconnect by serializing peer-connection state transitions.
  • CallKit + FaceID blocking
    Solved the locked-device + FaceID gate that was deferring CallKit reporting and dropping early audio frames.
Impact
  • Improved call connect rate and reliability across unstable networks
  • Cut user-reported audio incidents during active production rollout
  • Owned multiple production releases end-to-end as the iOS calling lead
SwiftSwiftUIWebRTCCallKitPushKitAVFoundationGraphQLWebSockets
Open in App Storeapps.apple.com
02Open Source · Educational
Open Source
Public on GitHub · Medium writeup

WebRTCDemo — One iOS codebase, four signaling options

Open-source reference implementation of WebRTC on iOS — async/await, actors, and four interchangeable signaling transports.

Published as a teaching artifact and architectural reference for engineers tackling WebRTC on iOS. One Swift codebase wraps RTCPeerConnection in async/await, ships four interchangeable signaling transports (clipboard JSON, step-by-step SDP/ICE exchange, Multipeer Connectivity over Bluetooth/WiFi, Local Network over Bonjour), and demonstrates production patterns for camera, audio, and lifecycle handling. Companion 3,500-word Medium post explains why signaling — not WebRTC itself — is the hardest part of real-time iOS.

Four signaling transports, one engine

Quick Test (clipboard JSON), Learn (step-by-step SDP/ICE), Multipeer (Bluetooth/WiFi auto-discovery), and Local Network (TCP + Bonjour) — all driving the same WebRTC core. Codable signaling messages make transports interchangeable.

Async/await wrappers around RTCPeerConnection

Replaced callback-based WebRTC APIs with structured concurrency: typed errors, cancellation support, and clean offer/answer flows that fit modern Swift.

Actor-isolated track manager

Camera and audio capture serialized through Swift actors; @MainActor ViewModels with nonisolated delegates handle the threading boundary correctly.

Peer-to-peer without a server

Multipeer Connectivity transport pairs and exchanges SDP/ICE over Bluetooth and local WiFi — no signaling server required for nearby-device calls.

SwiftSwiftUIWebRTCMultipeer ConnectivityNetwork.frameworkBonjourasync/awaitActors
View on GitHubgithub.com
03AI Product · Live
Live · App Store
Cinematic AI · Three universes

Aurekai — Where every world remembers you

AI-powered cinematic storytelling on iOS. You speak, the world responds — voiced, animated, and scored by a film-grade engine.

Built end-to-end as a product: a cinematic engine that turns user choices into voiced, animated, scored scenes across three original universes (Dark Myth · Sands of the Forgotten · Tides of the Broken Compass). The challenge wasn't 'call an LLM' — it was making it feel cinematic, fast, and sustainably cheap.

Cinematic engine

Pivotal scenes turn into animated film, voiced and scored. Scene-aware prompting, character continuity, and pacing that produce structured narratives, not generic chatter.

Three original universes

Dark Myth, Sands of the Forgotten, and Tides of the Broken Compass — each with its own characters, laws, and visual language. AUREKAI Originals as a content layer on top of the engine.

AI conversation system

Streaming responses, cancellable turns, and graceful degradation so the cinematic feel stays fluid on flaky connections.

Cost optimization

Prompt caching, context trimming, and tiered model routing — premium models where it matters, fast models everywhere else.

SwiftSwiftUILLM APIsPrompt cachingStreamingVoice synthesisAsync/Await
— shipped surfaces3 shots
Aurekai — Direct your own cinematic story
Aurekai — Watch it come alive
Aurekai — Three universes, every realm
Open in App Storeapps.apple.com
04Web Product · Live
Live · Web
Free · No signup · On-device

Zivyaa — Your Vedic chart, done properly

An AI-native Vedic astrology platform on the web — real ephemeris, real interpretations, runs on your device, no signup.

Built end-to-end as a web product: birth-chart computation in the browser using Astronomia (VSOP87) + Lahiri ayanamsha, verified against AstroSage and Drik Panchang. Layered with LLM-driven natural-language interpretation that cites the planet driving every answer. Designed for serious astrologers, not generic horoscope-app users.

Real ephemeris in the browser

Astronomia (VSOP87) + Lahiri ayanamsha — runs entirely on-device. No data uploaded, works offline. Cross-validated against AstroSage and Drik Panchang for accuracy.

Eight tools, not just a chart

Vedic Birth Chart (North/South/East styles), Panchang & Muhurat, Deep Numerology, Compatibility (36-point Ashta Koota), three Dasha systems, Yogas & Doshas, yearly horoscope, and 'Ask Your Chart' (LLM-grounded Q&A).

Multi-language platform

English first, with localization architecture built in from day one for global rollout. Geocoded birth cities, accurate to your exact location.

From birth time to insight in 60 seconds

Three-step funnel: enter details → compute real chart → explore depth not generics. Past/present/future life chapters, personalized remedies, downloadable PDF reports.

Next.jsReactTypeScriptTailwind CSSAstronomia (VSOP87)LLM APIsOn-device compute
— shipped surfaces3 shots
zivyaa.app
Zivyaa — Your Vedic chart, done properly
zivyaa.app
Zivyaa — Everything a Vedic astrologer expects
zivyaa.app
Zivyaa — From birth time to insight in 60 seconds
Visit Zivyaazivyaa.app
/05Systems & architecture

I designSystems.

— not just features

The systems behind the products — broken into the parts that actually matter, not flow charts. This is what shipping real-time and AI on iOS looks like up close.

/01System03

Real-time Communication

How a voice/video call survives cold start, FaceID, Bluetooth handoff, and a 3G dropout.

  • WebRTC signaling (GraphQL + WebSocket)
  • Call lifecycle handling (CallKit + PushKit)
  • Multi-device call synchronization
  • ICE restart and reconnect logic
  • Audio routing — AVAudioSession (BT / HFP / A2DP)
  • DTLS-SRTP media · STUN / TURN traversal
/02System03

AI Systems

How a chat turn becomes a cinematic, low-latency, cost-controlled response.

  • LLM pipeline orchestration
  • Prompt caching for repeated prefixes
  • Streaming responses · cancellable turns
  • Context compaction · scene state
  • Cost optimization · tiered model routing
/03System03

Networking Stack

GraphQL for queries, WebSockets for live signaling and presence — both with retry and backoff.

  • GraphQL — typed queries / mutations
  • WebSockets — signaling, presence, multi-device sync
  • Exponential backoff · idempotency keys
  • Race-free silent token refresh
  • Offline-tolerant queues & retry strategies
/06Problems I solve

Bugs that don'tShow in tutorials.

— a short, honest list

Production issues I've shipped fixes for — the kind that decide whether a real-time system is reliable or not.

Quick scan · top six
  • WebRTC audio failures in terminated iOS apps
  • CallKit + FaceID race conditions
  • Multi-device call synchronization
  • Real-time communication under unstable networks
  • SDP offer/answer race on reconnect
  • Database lock crash (0xdead10cc) at suspend time
  1. 01
    — Problem

    WebRTC audio failure in terminated state

    Pain

    Calls connected but came up silent when the app was launched cold via PushKit.

    Fix

    Reordered AVAudioSession activation against PushKit's runloop, hardened category negotiation, and verified with terminated-state regression tests.

  2. 02
    — Problem

    CallKit + FaceID lifecycle edge case

    Pain

    On locked devices, FaceID gating delayed CallKit reporting and the first 1–2 seconds of audio were lost.

    Fix

    Decoupled CallKit reporting from UI presentation and pre-warmed the peer connection so media flowed the moment the device unlocked.

  3. 03
    — Problem

    0xdead10cc — database lock crash

    Pain

    iOS killed the app at suspend time because a SQLite transaction was still holding a file lock.

    Fix

    Audited every background-suspended write path, scoped transactions to background tasks, and added a watchdog assertion in debug.

  4. 04
    — Problem

    Multi-device sync — ghost calls

    Pain

    Ringing on Device A while Device B had already picked up — a classic distributed-state bug.

    Fix

    Introduced an authoritative call-state event on the WebSocket channel and made every device a subscriber, not an owner.

  5. 05
    — Problem

    SDP offer/answer race

    Pain

    Under reconnect, offer and answer could interleave and the peer connection landed in a stalled state.

    Fix

    Serialized peer-connection state transitions through a single actor and made ICE restart explicit, not implicit.

  6. 06
    — Problem

    Bluetooth route flip mid-call

    Pain

    Headset disconnect mid-call would route audio to the receiver silently — users thought the call dropped.

    Fix

    Subscribed to AVAudioSession.routeChangeNotification, surfaced UI feedback, and re-prioritized the next-best route.

/07Recommendations

Words fromThe people I ship with.

— a real reference letter, drawn from the original document

Y
YEO Messaging
yeomessaging.com
Speedwell Mill, Old Coach Road, Tansley, Matlock, Derbyshire, DE4 5FY · United Kingdom
Subject
Reference for Abhishek Suryavanashi
Date · 13 April 2026

To whom it may concern,

It is my pleasure to provide this character and performance reference for Abhishek Suryavanashi, who worked under my supervision as an iOS Developer at YEO Messaging for over a year.

I would highly recommend him on the design and implementation of voice and video calling functionality on iOS — strong hands-on work with WebRTC integration, CallKit / PushKit, signalling flow handling, and debugging complex audio/video calling issues and production edge cases.

He worked very positively with the wider team, always contributing with great ideas. Very hardworking.

I have no hesitation in recommending Abhishek Suryavanashi for any future opportunities in mobile development / software engineering roles. I am willing to provide a verbal reference if required.

Highly recommended on
WebRTCiOS DevelopmentSwiftSwiftUIUIKitReal-time CommunicationMobile Application DevelopmentDebugging

Yours faithfully,

Valentinos Eleftheriades
Valentinos Eleftheriades
Director of Technical Operations · YEO Messaging
valentinos@yeomessaging.com+44 7538 342230
More recommendationsvia LinkedIn
August 27, 2025

“I had the pleasure of working with Abhishek Suryavanashi during our time at Qasr Almas Information Technology Co., where our paths crossed on several cross-functional projects involving iOS development and HR initiatives.

What truly sets Abhishek apart is his deep expertise and passion for crafting intuitive, high-performance iOS applications. His mastery of Swift, UIKit, and the entire Apple ecosystem consistently resulted in polished, user-friendly mobile solutions that exceeded expectations.

Beyond his technical proficiency, Abhishek brings a collaborative and solution-oriented mindset to every project. He's intuitive in translating business requirements into elegant design and optimized code, and regularly offered valuable technical insights during collaborative discussions. His proactive attitude, willingness to help teammates, and readiness to share knowledge made him a trusted resource and a joy to work alongside.

His work ethic is grounded in precision and innovation. Whether tackling a complex UI issue or refining application performance, Abhishek approaches challenges with thoughtful analysis and determination. His polished communication style — both with peers and stakeholders — helped bridge gaps between technical and non-technical teams, enhancing our collective efficiency.

In short, Abhishek is not just a brilliant Senior iOS Developer — he's a dependable collaborator who elevates the quality of any project he's part of. I wholeheartedly recommend him to any team or organization seeking a talented developer with both technical depth and exceptional teamwork skills.”

AN
Adhwaid Narayan
Human Resources & People Analytics · Qasr Almas Information Technology Co.
— Managed Abhishek directly
See all on LinkedIn
/08Tech stack

MyWorking stack.

— what I actually reach for

A toolkit shaped by years of production iOS — leaning hard into real-time communication, AI, and the boring parts that make systems reliable.

iOSSwift
iOSSwift 6 strict concurrency
iOSSwiftUI
iOSUIKit
iOSAsync/Await
iOSCombine
iOSGCD
iOSMVVM · VIPER · Clean Architecture
Real-timeWebRTC
Real-timeCallKit
Real-timePushKit (VoIP)
Real-timeAVFoundation · AVAudioSession
Real-timeICE · STUN · TURN
Real-timeSDP / DTLS-SRTP
BackendGraphQL
BackendWebSockets
BackendREST
BackendRetry · Backoff · Idempotency
BackendReal-time signaling
AILLM integration
AIPrompt caching
AIStreaming responses
AIContext compaction
AICost optimization
ToolingGit · Bitbucket
ToolingCI/CD · Jenkins
ToolingTestFlight · App Store
ToolingCrashlytics
ToolingJira · Confluence
ToolingAgile / Scrum
/01
iOS
8 tools
/02
Real-time Communication
6 tools
/03
Backend & Networking
5 tools
/04
AI
5 tools
/05
Tooling & Delivery
6 tools
/09Experience

Seven yearsShipping iOS.

— India · UAE · UK

Consumer apps, B2B platforms, and a flagship real-time communication system — across three countries and a decade of production releases.

  1. /06Jan 2025 — Present

    Senior iOS Engineer — WebRTC / CallKit

    Smart Working · client YEO Messaging (UK)

    Owned the production WebRTC voice & video system for YEO Messaging / YEO Business. CallKit, PushKit, signaling, multi-device sync, audio routing, and locked-state lifecycle.

  2. /05May 2023 — Aug 2024

    Software Developer — iOS

    Qasr Almas Information Technology Co. · Dubai, UAE

    Delivered consumer iOS applications across utilities, travel, and marketplace domains. Built workforce-management features (location, QR check-ins, role-based access) and shipped multiple App Store releases with Arabic/English localization.

  3. /04Oct 2021 — Dec 2022

    iOS Developer Consultant — McDonald's

    Capgemini India · Pune

    Feature work and production-issue resolution on the McDonald's consumer iOS app. MVVM / VIPER, CI/CD, cross-platform collaboration on a high-traffic codebase.

  4. /03Oct 2019 — Sep 2021

    iOS Developer

    Plexasys Solutions · Nagpur

    Shipped multiple production iOS apps end-to-end across consumer and B2B domains.

  5. /02Oct 2018 — Jun 2019

    iOS Developer

    Netnaca Pvt. Ltd. · Nagpur

    Feature development, API integration, and App Store releases for client iOS products.

  6. /01Jan 2017 — Aug 2018

    iOS Developer

    Phian Infotech Pvt. Ltd. · Nagpur

    Started iOS career — fundamentals, production discipline, and the first App Store releases.

/10Writing

Notes fromProduction iOS.

— long-form on Medium

Posts on real-time communication, iOS lifecycle, and shipping AI products.

MediumFeb 8, 20268 min

Building an Audio & Video App with WebRTC on iOS: One Codebase, Four Signaling Options, Zero…

Building an Audio & Video App with WebRTC on iOS: One Codebase, Four Signaling Options, Zero Backend If you’ve ever tried to build a peer-to-peer video call on iOS using native WebRTC, you know the pain. The official doc…

webrtcaudio-callsignalingswift
Read on Medium
MediumOct 30, 20244 min

Add Game Center Leaderboards to Your iOS Game: A Step-by-Step Guide

Integrating Game Center in your iOS game can significantly enhance user engagement by allowing players to compare their scores on global leaderboards. In this tutorial, I’ll guide you through creating a Game Center Leade…

ios-developmentswiftgamecentergame-development
Read on Medium
MediumOct 23, 20244 min

Building a 2048 PowerPlay Game for Apple Watch with SwiftUI

In this post, I’ll walk you through how I built a 2048 PowerPlay game for the Apple Watch using SwiftUI. This is an extension of my earlier project where I created the game for iPhone and iPad, which I covered in this Me…

swiftui2048-gameiosgame-development
Read on Medium
MediumOct 19, 20244 min

Building “2048 - PowerPlay” game with SwiftUI

Introduction As an iOS developer with over six years of experience, I’ve always enjoyed taking on new challenges, whether it’s building feature-rich apps or exploring unique projects. Recently, I embarked on an exciting …

mobile-apps2048game-developmentswiftui
Read on Medium
All posts on Medium
/11Contact

When you'reready to shipsomething real.

I read every email. Usually reply within 24 hours.

— channels
  1. /01
    PrimaryEmail
    aysuryawanshi6@gmail.com
  2. /02
    ProfessionalLinkedIn
    linkedin.com/in/abhisheksuryavanashi
  3. /03
    ProductsApple App Store
    Apps under Abhishek Suryavanashi
  4. /04
    WritingMedium
    medium.com/@iosdev.abhi
  5. /05
    CodeGitHub
    github.com/abhisheksuryawanshi
— availability
Open for senior iOS / RTC roles
Response
< 24 hours
Timezone
IST · UTC+5:30
Based
Nagpur, India · Remote
Get in Touch
— sign-off
— Abhishek