Hiring Guide: Expo Developers
Hiring Expo developers is about more than knowing React Native—it's about shipping polished iOS and Android apps faster by leaning on the Expo platform (bundler, EAS, OTA updates, and managed services) while keeping escape hatches ready for native needs. The best Expo engineers balance velocity with quality: they design reliable app architecture, keep performance crisp, integrate native modules via config plugins when required, and navigate app store reviews without surprises. This guide gives you a practical path to scope the role, spot strong candidates, interview for real-world signals (not trivia), and plan the first 30–90 days. It also links to related Lemon.io roles to round out your team.
Why Teams Choose Expo (and When It Fits)
- Speed to market: Expo’s managed workflow, OTA updates, and EAS Build/Submit cut setup time and reduce friction in CI/CD and store delivery.
- Modern tooling out of the box: TypeScript support, Metro bundler, Expo Router, asset pipeline, updates, notifications, and deep link helpers save weeks of groundwork.
- Cross-platform consistency: One codebase targets iOS/Android (and often web) with consistent APIs and device integrations.
- Native escape hatch: With config plugins and the bare workflow, teams can integrate native SDKs or custom modules without abandoning Expo’s ecosystem entirely.
What Great Expo Developers Actually Do
- Architect apps for reliability: Choose state management appropriate to scope (React Query/Zustand/Redux Toolkit), keep server cache separate from UI state, and define a predictable navigation model with Expo Router.
- Design for performance: Split bundles by route, lazy load heavy screens, prefetch critical assets, limit re-renders, and keep startup times tight on low-end Android devices.
- Integrate native capabilities the right way: Use Expo SDK modules where possible (camera, sensors, haptics) and reach for config plugins or bare workflow only when necessary (advanced payments, low-level BLE, custom media pipelines).
- Harden the release path: Use EAS for deterministic builds, code signing, credentials, and store submission. Gate releases with automated tests, crash/error monitoring, and staged rollouts.
- Ship safely with OTA updates: Segment updates by channel, link updates to feature flags, and plan rollback paths. Keep server-driven feature gating to minimize resubmissions.
- Respect privacy & platform rules: Manage permissions (camera/location/notifications) with just-in-time prompts and clear explanations. Handle iOS App Tracking Transparency where applicable.
- Make quality measurable: Wire analytics, performance traces, and crash reporting. Track cold start P50/P95, interaction latency (INP-like), and crash-free sessions; enforce thresholds in CI.
Common Use Cases for Expo (Map Them to Candidate Profiles)
- Consumer apps: Onboarding, push notifications, deep links, in-app purchases, social login, and media capture—requires store savvy and accessible UI polish.
- E-commerce & subscriptions: Product discovery, carts, payments, receipts, and entitlement checks; performance and offline fallback matter.
- Productivity & collaboration: Realtime sync, offline queues, background tasks, and conflict resolution; benefits from a well-designed data layer.
- Prototyping to production: Rapid iteration with OTA updates and preview builds for stakeholders; later harden with testing, observability, and policy compliance.
Managed vs. Bare Workflow (and Config Plugins)
- Managed workflow: Fastest start, Expo-first APIs, minimal native code. Ideal until you need deep native integrations. Use plugins to extend without ejecting.
- Bare workflow: Full native control (Xcode/Gradle) while still leveraging Expo modules and EAS. Choose this when you need custom native features, bespoke background services, or SDKs not covered by plugins.
- Config plugins: Automate native changes at build time (Info.plist, AndroidManifest.xml, Gradle). Great candidates can author and maintain plugins to keep your app close to managed while integrating vendor SDKs.
Core Skills & Technologies for Expo Devs
- React Native & Expo SDK: Navigation (Expo Router), gestures/reanimated basics, asset handling, updates, notifications, media, sensors.
- TypeScript: Strong typing culture (props, hooks, API contracts), Zod/valibot for runtime validation where helpful.
- State & data: React Query/SWR for server cache, lightweight stores for UI state, optimistic updates, pagination, and query invalidation.
- Performance: Bundle analysis, memoization, virtualization, image optimization, FastImage-like patterns, and avoiding unnecessary bridge crossings.
- Security & privacy: Secure storage for tokens, protected routes, keychain/keystore practices, encryption in transit, and minimal PII in logs.
- DevOps with EAS: Build profiles, credentials, store submission, environment secrets, and channel-based OTA releases; CI triggers and quality gates.
- Testing: Unit (Vitest/Jest), component (React Native Testing Library), and e2e (Detox/Maestro). Snapshot and accessibility checks for critical screens.
- Store readiness: App icons/splash, permission copy, privacy nutrition labels, ATT prompts, and review remediation workflows.
Define the Expo Role Clearly (Before You Post)
- Outcomes (90–180 days): “Crash-free sessions ≥ 99.5%,” “Cold start P95 < 3s on mid-range Android,” “Checkout funnel conversion +3%,” “App Store and Play acceptance on first submission,” “Release cadence: weekly OTA + monthly store builds.”
- Feature surface: Auth flows, push notifications, payments, media, location, BLE, offline-first requirements, and any vendor SDKs to integrate.
- Data & APIs: REST/GraphQL, realtime (WS/SSE), pagination, error contracts; who owns schema evolution and versioning?
- Privacy & compliance: Consent flows, ATT, data retention, analytics scope, lawful bases where relevant, accessibility targets (WCAG-inspired for mobile).
- Release process: EAS pipelines, OTA channels, staging/beta tracks, rollout and rollback policy, and alert thresholds.
Sample Job Description (Copy & Adapt)
Title: Expo Developer — React Native • EAS • OTA Releases
Mission: Deliver a fast, reliable cross-platform app with Expo, integrating native capabilities via plugins when needed and maintaining a safe, measured release cadence.
Responsibilities:
- Build features with Expo/React Native using Expo Router, typed APIs, and accessible components.
- Own EAS workflows: build profiles, signing, submission, OTA channels, and environment secrets.
- Integrate vendor SDKs via config plugins or bare modules; document and test native changes.
- Optimize performance (startup, images, lists) and add telemetry to monitor regressions.
- Ship with quality gates (unit/component/e2e), feature flags, and progressive rollout strategy.
Must-have skills: Expo SDK, React Native, TypeScript, EAS, state/data fetching patterns, store submission experience, and testing basics (Jest/Detox).
Nice-to-have: Config plugin authoring, bare workflow native work (Swift/Kotlin), GraphQL, payments, advanced notifications, and background tasks.
How to Shortlist Expo Candidates (Portfolio Signals)
- Shipping history: Live apps with store links, version history, rankings/reviews, and clear changelogs.
- Release discipline: Evidence of EAS pipelines, OTA channels, staged rollouts, and quick hotfixes with postmortems.
- Native integration receipts: Config plugins or bare modules that integrate payments, media, or specialized hardware.
- Performance & reliability: Metrics for startup time, crash-free sessions, and interaction smoothness; dashboards/screenshots help.
- Accessibility & UX polish: Keyboard navigation where relevant, screen reader support, color contrast, and motion preferences.
- Testing & QA: Demonstrated e2e setups, flaky test remediation, and CI gates that block on quality thresholds.
Interview Kit (Signals Over Trivia)
- Architecture & state: “Design the data flow for a product detail screen with reviews and cart. What is server cache vs. UI state? How do you avoid unnecessary re-renders?”
- Performance: “Startup is slow on Android Go devices. What profiling steps and asset/code changes get P95 cold start under 3 seconds?”
- Native integration: “A vendor SDK requires Info.plist and Gradle edits plus a manifest permission. Walk through a config plugin approach and how you’d test it in CI.”
- OTA strategy: “How do you structure release channels, feature flags, and rollback to prevent user-facing breakage?”
- Auth & security: “Implement secure token storage and refresh. How do you protect sensitive screens and handle biometric unlock?”
- Store submission: “The app was rejected for unclear permission usage. What’s your remediation plan (UI copy, permission timing, privacy disclosures)?”
First 30/60/90 Days With an Expo Developer
Days 1–30 (Stabilize & Baseline): Set up EAS projects, credentials, and build profiles; configure error and performance monitoring; audit permissions and privacy copy; identify top crash and latency sources; ship a thin vertical slice with feature flags and OTA channel.
Days 31–60 (Accelerate & Integrate): Introduce standard data-fetching patterns (React Query/SWR), refactor heavy screens for bundle splitting and virtualization, implement push notifications or deep links, add Detox/Maestro flows for critical journeys, and tighten CI gates.
Days 61–90 (Scale & Harden): Integrate any required native SDKs via config plugins; finalize accessibility fixes; implement staged rollout policies; document runbooks and add dashboards for crash-free rate, startup metrics, and funnel health.
Scope & Cost Drivers (Set Expectations Early)
- Native complexity: The number and depth of vendor SDKs or device integrations (payments, BLE, DRM) drive plugin/bare-workflow effort.
- Performance targets: Aggressive startup and interaction budgets require careful asset pipelines, code-splitting, and audit time.
- Offline & realtime: Conflict resolution, background sync, and push messaging add development and QA cycles.
- Compliance: ATT prompts, data retention, and localization of disclosures require policy work and extra testing.
- Testing matrix: Supporting a range of iOS/Android OS versions and device classes increases e2e coverage and device-farm costs.
Internal Links: Related Lemon.io Roles
Call to Action
Get matched with vetted Expo Developers—share your feature roadmap, native integration needs, and release cadence so we can send curated profiles ready to ship.
FAQ
- Is Expo production-ready?
- Yes—many teams run production apps on Expo. Use managed workflow for speed, and switch to config plugins or bare workflow when you need deeper native control. Pair it with solid testing, observability, and EAS for a robust release process.
- When should we use the bare workflow?
- Go bare when you require unsupported native SDKs, background services beyond Expo’s scope, or heavy customization in Xcode/Gradle. You can still leverage Expo modules, EAS, and updates in bare.
- How do OTA updates work with store rules?
- Serve updates via channels for bug fixes and minor UI changes; structural changes that affect native code still require store resubmission. Keep release notes transparent and plan rollbacks per channel.
- How do we keep performance snappy?
- Optimize images, lazy load routes, virtualize lists, memoize expensive components, reduce bridge crossings, and monitor startup and interaction metrics across devices. Enforce budgets in CI.
- What’s the right testing strategy?
- Unit tests for logic, component tests for states, and a lean e2e suite (Detox/Maestro) for critical funnels. Run tests in CI per PR and block merges when crash or performance budgets are exceeded.
- Can we integrate payments and subscriptions with Expo?
- Yes—with vendor SDKs or server-mediated flows. For native IAPs, plan a config plugin or bare module; ensure entitlement checks, receipt validation, and robust error handling.
