--- title: "Hire Callstack | Expert Engineering & Agentic Delivery" description: "Hire senior engineers to build and scale React and React Native products, or work with Callstack on custom agents and AI delivery workflows." url: https://www.callstack.com/contact updated: 2026-11-06T10:02:45.500Z --- # Hire Callstack | Expert Engineering & Agentic Delivery Hire senior engineers to build and scale React and React Native products, or work with Callstack on custom agents and AI delivery workflows. React Foundation · used by 50M+ developers · 100+ Enterprises ## Talk to Callstack. Share what you’re working on or book a call with our team. [sales@callstack.com](mailto:sales@callstack.com) · [Book consultation](https://calendly.com/d/dv34-csx-cqb/meeting-with-callstack) - **5x** faster message sending time (Expensify) · [Case study](https://www.callstack.com/case-studies/enhancing-applications-performance-for-expensify) - **10** min from code change to mini-app release (Teamworks) · [Case study](https://www.callstack.com/case-studies/accelerating-teamworks-mobile-delivery-with-re-pack-and-module-federation) - **-28%** CPU usage in critical trading flows (Questrade) · [Case study](https://www.callstack.com/case-studies/migrating-questrade-edge-mobile-to-a-faster-more-scalable-architecture) - **2×** Estimated AI-assisted delivery speedup (JetBrains) · [Case study](https://www.callstack.com/case-studies/building-storybook-connect-for-jetbrains-in-25-working-days) - **25** Working days from kickoff to merge (JetBrains) · [Case study](https://www.callstack.com/case-studies/building-storybook-connect-for-jetbrains-in-25-working-days) - **1** Plugin across three frameworks (JetBrains) · [Case study](https://www.callstack.com/case-studies/building-storybook-connect-for-jetbrains-in-25-working-days) - **multi-daily** staging deployments instead of weekly releases (Teamworks) · [Case study](https://www.callstack.com/case-studies/accelerating-teamworks-mobile-delivery-with-re-pack-and-module-federation) - **7** mini-apps supported in one modular mobile platform (Teamworks) · [Case study](https://www.callstack.com/case-studies/accelerating-teamworks-mobile-delivery-with-re-pack-and-module-federation) - **2** CI/CD lanes for mini-app and host-app distribution (Teamworks) · [Case study](https://www.callstack.com/case-studies/accelerating-teamworks-mobile-delivery-with-re-pack-and-module-federation) - **2x** growth in mobile user base during the migration period (AutoZone) · [Case study](https://www.callstack.com/case-studies/migrating-ios-and-android-apps-to-react-native-for-autozone) - **4.2 -\> 4.7** app rating increase after migrating to React Native (AutoZone) · [Case study](https://www.callstack.com/case-studies/migrating-ios-and-android-apps-to-react-native-for-autozone) - **0** missed releases during the transition to React Native (AutoZone) · [Case study](https://www.callstack.com/case-studies/migrating-ios-and-android-apps-to-react-native-for-autozone) - **33%** fewer re-renders across most features (Questrade) · [Case study](https://www.callstack.com/case-studies/migrating-questrade-edge-mobile-to-a-faster-more-scalable-architecture) - **18%** faster time-to-interactive (Questrade) · [Case study](https://www.callstack.com/case-studies/migrating-questrade-edge-mobile-to-a-faster-more-scalable-architecture) - **78%** bundle size reduction (from 50 MB to 11 MB) (Dream11) · [Case study](https://www.callstack.com/case-studies/improving-chat-performance-for-dream11) - **30%** faster component mount time after render optimization (Dream11) · [Case study](https://www.callstack.com/case-studies/improving-chat-performance-for-dream11) - **60%** faster initial load time enabled by switching to Hermes (Dream11) · [Case study](https://www.callstack.com/case-studies/improving-chat-performance-for-dream11) - **4.5x** faster search screen loading time (Expensify) · [Case study](https://www.callstack.com/case-studies/enhancing-applications-performance-for-expensify) - **#1** SEO rank, recovering from 3-9 (AutoZone) · [Case study](https://www.callstack.com/case-studies/migration-to-nextjs-for-autozone) - **260kB** less in blocking JS payload (AutoZone) · [Case study](https://www.callstack.com/case-studies/migration-to-nextjs-for-autozone) - **2–5x** faster feedback loop (AutoZone) · [Case study](https://www.callstack.com/case-studies/migration-to-nextjs-for-autozone) - **2.8x** increase in knowledge over 8 weeks (25% → 71% assessment scores) (Hello Fresh) · [Case study](https://www.callstack.com/case-studies/training-hellofresh-engineers-to-build-production-apps-with-react-native) - **15** developers trained across web and native backgrounds (Hello Fresh) · [Case study](https://www.callstack.com/case-studies/training-hellofresh-engineers-to-build-production-apps-with-react-native) - **86%** of devs self-rated their knowledge as 3/5 or higher after training (up from 0%) (Hello Fresh) · [Case study](https://www.callstack.com/case-studies/training-hellofresh-engineers-to-build-production-apps-with-react-native) - **130%** increase in users post-upgrade (7cups) · [Case study](https://www.callstack.com/case-studies/modernizing-react-native-codebase-for-7cup) - **63%** adoption rate; majority of attendees registered in the app (React Universe App) · [Case study](https://www.callstack.com/case-studies/react-universe-app-networking-evolved-with-liquid-glass) - **67%** of attendees connected through QR badge sharing (React Universe App) · [Case study](https://www.callstack.com/case-studies/react-universe-app-networking-evolved-with-liquid-glass) - **45%** created personalized badges to showcase identity and goals (React Universe App) · [Case study](https://www.callstack.com/case-studies/react-universe-app-networking-evolved-with-liquid-glass) - **49%** of attendees onboarded before day one, arriving ready to network (React Universe App) · [Case study](https://www.callstack.com/case-studies/react-universe-app-networking-evolved-with-liquid-glass) ### Tell us what you’re working on. We’ll connect you with the right expert within 24 hours. [Contact form](https://www.callstack.com/contact#form) Clients ## Trusted by enterprise teams at scale. > The team at Callstack are the most experienced engineers in the React Native community. > > — Nader Dabit, Senior Developer Advocate / AWS > If you're looking for skilled and trusted React Native developers, Callstack is definitely the way to go. > > — Tom Occhino, Director of Engineering / Meta > Their engineers proved to be a crucial part of our mobile app relaunch project. > > — Brian Aznar, Engineering Director / MLS > The trainers are always very helpful and supportive. It really makes a difference! > > — Artem Musiienko, Staff Eng / Hello Fresh > I appreciate their attention to detail, flexible approach and a high degree of expertise. > > — Glen Moriarty, Founder and CEO / 7cups > We had been struggling with React Native application performance until we met Callstack. > > — Huỳnh Chí Hùng, Associate Director / MoMo > I recommend them as a trusted tech partner for running complex projects. > > — Jin Chung, Co-Founder, CTO / Rainbow > Teamworks needed Module Federation, we helped make it real > > — Michael Song, Head of Platform / Teamworks > Not only does Callstack have tremendously talented engineers, but I know they care about the success of the project as much as I do. > > — TC Davis, Product / Expo ## Contact us ### Open source Questions about projects, sponsorships, or community? [hello@callstack.com](mailto:hello@callstack.com?subject=Open%20source%20question) ### Career Interested in joining Callstack? Contact us about open roles, hiring, and recruitment. [recruitment@callstack.com](mailto:recruitment@callstack.com?subject=Career) ### Wrocław HQ Prosta 36 53-508 Wrocław, Poland ### Vienna / Margelo Barichgasse 38/3.5 1030 Vienna, Austria ### San Francisco 945 Market Street San Francisco CA 94103, US