--- title: "Build & Test Acceleration" description: "Shorten build and test feedback loops with caching, parallelization, and runners tuned to your workloads." url: https://www.callstack.com/services/build-test-acceleration updated: 2026-11-06T10:09:23.052Z --- # Build & Test Acceleration Shorten build and test feedback loops with caching, parallelization, and runners tuned to your workloads. _[Expert Engineering](/ai-native-engineering) › [Enterprise Infrastructure](/capabilities/self-hosted-ci-cd-infrastructure)_ **Feedback in minutes, not coffee breaks** Slow builds tax every engineer and every agent, on every change. We profile your build and test pipeline, then attack the top offenders with caching, parallelization, and hardware tuned to the workload. [Book a call](#contact) · [How it works](#what-you-get) ## Enterprise Infrastructure - ISO 27001 certified - 100+ Enterprise projects delivered - React Foundation Founding Member · 300+ commits to React Native · Contributing since 2016 - Industry runs on our tooling · 50M+ OSS downloads / month - 10 min From code change to mini-app release - 60 → 10min Faster builds after replacing Jenkins with EAS ## What you get: Every loop, measurably shorter. - **Build profiling** Where the minutes actually go: measured, not guessed. - **Remote and local caching** Compilation and dependency caches shared across CI and developer machines. - **Test parallelization** Suites split, sharded, and balanced across runners. - **Runner tuning** Machine classes matched to workloads, with Apple silicon where it pays. - **Selective execution** Only affected tests and targets run per change. - **Regression guardrails** Build-time budgets enforced in CI, so speed does not erode back. **Get your minutes back.** Measured acceleration across build and test, with budgets that keep it fast. [Book a call](#contact) ## How we work together: Improve the system without disrupting delivery. ### Extend your team (1 week) Our senior engineers join your team to ship features, guide technical decisions, and strengthen delivery. - Your roadmap and workflow - Expertise shared as we work - Flexible timezone coverage ### Deliver a project (1-12 months) We take agreed work from technical planning to release, with clear responsibilities and progress you can see. - 3 Callstack engineers ship like 6 - Impact visible before sprint two - End-to-end delivery ### Solve specific challenge (as needed) We address a performance, migration, or infrastructure challenge, or run training around your team’s needs. - Focused reviews or implementation - Knowledge your team keeps - Outcomes guaranteed with contract ## What shipping at AI speed looks like. - [Accelerating Teamworks' Mobile Delivery With Re.Pack and Module Federation](/case-studies/accelerating-teamworks-mobile-delivery-with-re-pack-and-module-federation): 10 min from code change to mini-app release - [Migrating iOS and Android Apps to React Native for AutoZone](/case-studies/migrating-ios-and-android-apps-to-react-native-for-autozone): 2x growth in mobile user base during the migration period - [Cutting Mobile Build Times by Up to 79% for a Southeast Asian Bank](/case-studies/cutting-mobile-build-times-by-up-to-79-for-a-southeast-asian-bank): 2.4× faster iOS cache-hit builds on average - [Building Scalable Observability for a High-Growth React Native App](/case-studies/building-scalable-observability-for-a-high-growth-react-native-app): 3→1 analytics systems unified into a single interface **Get your minutes back.** Measured acceleration across build and test, with budgets that keep it fast. [Book a call](#contact) > We had been struggling with React Native application performance until we met Callstack. > > — Huỳnh Chí Hùng, Associate Director / MOMO We’ll connect you with the right expert within 24 hours. ## Let’s find the right path for your product. Still have questions? Whether you’re planning new work or unblocking an existing product, we’ll help you choose the right path forward. **What gains should we expect?** Starting points vary too much for one number, but native build caching and test sharding routinely cut feedback time by half or better. The profiling phase quantifies it for your pipeline first. **Does this work in a monorepo?** Yes. Affected-target detection and per-package caching are exactly where monorepos win back the most time. **Can you fix React Native native build times specifically?** Yes. iOS and Android compilation, dependency prebuilds, and CI cache design for native artifacts are core to this work. **What does caching infrastructure cost to run?** A fraction of what it saves in runner minutes and engineer wait time. We include the infrastructure cost in the before/after math. **Does it work with EAS or hosted CI?** Yes. Acceleration applies whether you build on EAS, hosted CI, or your own runners - the techniques move with you. **How do we keep it fast afterwards?** Build-time budgets in CI fail a PR that regresses the pipeline, the same way a failing test would. [Book consultation](#contact) ## Open source - [React Native Community CLI](https://github.com/react-native-community/cli): Command line tools to help you build React Native apps - [Re.Pack](https://re-pack.dev/): A webpack-based toolkit to build your React Native application with full support of webpack ecosystem - [React Native Builder Bob](https://github.com/callstack/react-native-builder-bob): Simple set of CLIs to scaffold and build React Native libraries for different targets - [Rock](https://www.rockjs.dev/): Modular toolkit for teams building React Native apps - [Agent Skills](https://github.com/callstackincubator/agent-skills): Callstack’s best practices on React Native performance optimization, upgrading, CI workflows, and brownfield migrations Insights ## Worth your time, by engineers. [Explore Insights](https://www.callstack.com/insights) - [Automating React Native Evals With Airflow](https://www.callstack.com/blog/automating-react-native-evals-with-airflow) (Aug 21 · Article): React Native Evals tests coding models on real React Native tasks. This article follows one automated run from model selection through solving, judging, result tracking, and human review. - [Unlocking Expo Updates in an Isolated Brownfield Architecture with SDK 55](https://www.callstack.com/blog/unlocking-expo-updates-in-an-isolated-brownfield-architecture-with-sdk-55) (May 18 · Article): Expo Updates used to be a pain point for teams running an Isolated Brownfield architecture. This guide shows how to get it working with Expo SDK 55, including iOS packaging, the current Android workaround, and end-to-end OTA update testing. If you're shipping React Native inside an existing native app, this walkthrough helps you get setup faster without guessing through the hard parts. - [How to Release a React Native App on the Meta Horizon Store](https://www.callstack.com/blog/how-to-release-a-react-native-app-on-the-meta-horizon-store) (Nov 20 · Article): This article walks through the full release flow for React Native apps on Meta Quest, from preparing a production build to submitting it through the Horizon Store. Developers will learn the technical steps, required tools, and best practices for store‑ready assets. It also highlights common review pitfalls, guidance for creating high‑quality screenshots, monetization options, and tips for shaping a smooth submission workflow. By the end, readers will understand how to take a Quest app from development to a polished, store‑ready release. - [Re.Pack 5.2: Faster Babel Transforms, RN 0.80 & 0.81, Rozenite](https://www.callstack.com/blog/re-pack-5-2-faster-babel-transforms-support-for-rn-0-80-0-81-rozenite) (Aug 27 · Article): Re.Pack 5.2 is out! This release focuses on parallel, smarter transforms with a new Babel & SWC loader, official support for React Native 0.80 and 0.81, fully typed configs, support for Rozenite and more. - [Caching React Native Builds on S3 and R2 With Rock](https://www.callstack.com/blog/caching-react-native-builds-on-s3-and-r2) (Jun 19 · Article): One of the core reasons we built Rock was to eliminate unnecessary native iOS and Android builds by reusing existing artifacts: saving time, compute, and cost. Until now, remote caching was tied to GitHub, which limited flexibility. The latest release changes that: Rock now supports AWS S3 and Cloudflare R2, allowing teams to store and retrieve native builds from their own infrastructure. This unlocks a much more powerful setup for enterprise teams with custom CI or compliance needs. - [We’re Building a New React Native Framework](https://www.callstack.com/blog/were-building-a-new-react-native-framework) (Mar 14 · Article): Building large React Native apps can be challenging, with slow build times, complex integrations, and mixed tech stacks. We're developing a new framework designed for enterprise apps that optimizes build reuse, CI speed, and cloud integration while staying flexible and self-hosted. - [Shipping Fast With Continuous Deployment](https://www.callstack.com/blog/shipping-fast-with-continuous-deployment) (May 10 · Article): Continuous Deployment (CD) lets you automate the critical steps of building, testing, and releasing your mobile apps. This guide walks through setting up CD pipelines with fastlane and AppCenter to ship new features and fixes faster without the manual toil. - [Ship OTA (Over-The-Air) When in an Emergency](https://www.callstack.com/blog/ship-over-the-air-when-in-an-emergency) (May 14 · Article): Shipping critical updates to mobile apps can be painfully slow, but React Native's over-the-air (OTA) updates let you push fixes directly to users in minutes. We walk through how to set up OTA updates with App Center/CodePush or EAS Update to deploy changes instantly when you need them most. - [Mastering Fastlane: Overcoming Challenges in Passing Build Properties to Native Layers](https://www.callstack.com/blog/passing-build-properties-to-native-layers-with-fastlane) (Aug 4 · Article): Fastlane is a powerful tool for automating development tasks, but it has some nuances. This guide shares practical tips for reliably updating plist files in iOS projects and passing custom properties to Gradle builds in Android apps. - [How Can Continuous Integration (CI) Improve Your React Native Apps?](https://www.callstack.com/blog/how-continuous-integration-can-improve-react-native-apps) (Dec 13 · Article): Continuous Integration (CI) can help React Native teams ship faster and with more confidence. By automating builds and tests, CI provides quick feedback on code changes, catches regressions early, and reduces manual testing effort. This article explores how to set up CI for React Native apps using popular tools like CircleCI and EAS Build. - [Continuous Delivery - Integration for Everyone](https://www.callstack.com/blog/continuous-delivery-integration-for-everyone) (Apr 24 · Article): Continuous integration and delivery can be tricky to set up, especially for mobile apps. This guide walks through a real-world example of configuring CircleCI, Fastlane, and App Center to automate builds, tests, code quality checks, and beta distribution for a React Native app. - [Bob - The React Native Library Builder](https://www.callstack.com/blog/bob-the-react-native-library-builder) (Apr 12 · Article): Bob is a new tool that aims to simplify and standardize the process of building and publishing React Native libraries. It handles compiling JavaScript and TypeScript code for different targets, generating type definitions, and more - so you can focus on writing your library code. - [Can Engineers Trust AI Agent Fleets? Nishant Gupta on Scale and Reliability](https://www.callstack.com/podcasts/can-engineers-trust-ai-agent-fleets-nishant-gupta-on-scale-and-reliability) (Oct 12 · Podcast): Nishant Gupta of Meta explains AI agent fleets, reusable control planes, and why verifying outcomes still matters as teams delegate more work. - [Observability and OpenTelemetry in React Native](https://www.callstack.com/podcasts/observability-opentelemetry-in-react-native) (Aug 13 · Podcast): Learn how Embrace and OpenTelemetry can help React Native teams standardize observability and improve app monitoring across platforms. - [Build Faster and Scale Smarter With Rock](https://www.callstack.com/podcasts/build-faster-with-rock) (Jun 10 · Podcast): Discover how Rock cuts build times, streamlines CI, and simplifies large-scale app development for growing teams. - [How to Handle App Center Retirement](https://www.callstack.com/podcasts/how-to-handle-app-center-retirement) (Oct 29 · Podcast): Discover App Center alternatives for React Native. Explore migration tips and Expo's role in the transition from CodePush & other App Center functionalities. - [Native Apps Without a Build Step](https://www.callstack.com/events/native-apps-without-a-build-step-2) (Sep 13 · Talk): Discover Rock by Callstack: the open, modular, self-hosted framework for React Native. Built to help teams scale, migrate, and deliver faster in the evolving React Native ecosystem. - [Observability for Application Deployments](https://www.callstack.com/events/observability-for-application-deployments) (Jun 24 · Talk): Discover practical observability techniques to pinpoint and fix slow deployments, optimize global performance, and deliver faster apps. - [Elevate Your React Native Observability With OpenTelemetry](https://www.callstack.com/events/elevate-your-react-native-observability-with-opentelemetry) (Jun 24 · Talk): Learn how to leverage OpenTelemetry to gain deeper, real-time insights into your React Native apps and significantly improve user experience. - [Live Dev Session: React Native Styling, OTA, and UI Tools](https://www.callstack.com/events/live-dev-session-react-universe-news-tools-code-2) (Jun 17 · Live Stream): Tune in to a live session unpacking React Native 0.80, OTA alternatives, AI-generated UIs, styling wars, and some truly wild tech tangents. - [Native Apps Without a Build Step](https://www.callstack.com/events/native-apps-without-a-build-step) (Apr 24 · Talk): Learn how Callstack’s new React Native framework slashes CI times and simplifies enterprise-scale mobile development. - [From Hours to Minutes: Making Your React Native CI Builds 20x Faster](https://www.callstack.com/events/from-hours-to-minutes-making-your-react-native-ci-builds-20x-faster) (May 12 · Webinar): Discover how to skip 90% of native builds in React Native CI using Rock. Includes a live demo and cost-saving insights from Expensify’s setup. - [Why You Need Rock](https://www.callstack.com/events/why-you-need-rock) (Mar 27 · Webinar): Learn more about Callstack's Rock straight from its creators. - [Unlocking Hidden Data: RUM for Effective App Optimization and Decision Making](https://www.callstack.com/events/unlocking-hidden-data-rum-for-effective-app-optimization-and-decision-making) (Jul 19 · Talk): Explore how RUM data reveals user behavior, solves app mysteries, and boosts conversions with smart metrics for better product decisions. - [New React Native Framework for Enterprise Announcement](https://www.callstack.com/events/new-react-native-framework-for-enterprise-announcement) (Mar 4 · Live Stream): We know what it takes to make React Native work for serious-scale applications. That’s why we created Rock, so enterprise teams can build with confidence, efficiency, and full control over their stack.