Own the pipeline from build to rollback.
Continuous Delivery infra
Scalable pipelines for rollouts, feature flags, A/B tests, and store submissions. Safer, faster delivery.
Faster iOS and Android builds
Remote caching and reusable artifacts cut Expensify builds from 25 min to 90 s, with faster feedback on both platforms.
Self-hosted OTAs
Over-the-air updates with staged rollouts, rollback, and secure delivery. No third-party update provider.
Faster testing cycles
Reusable native build artifacts shared across CI jobs cut test time and lift throughput for QA teams.
No vendor lock-in
Everything runs on your infrastructure. Full control over build, release, and recovery, no third parties.
Open source at the core
Built on Rock, our open-source framework: a drop-in replacement for the Community CLI your team can audit and extend.
Design → Build → Extend
Build delivery infrastructure your team owns.
Design
We map the mobile delivery stack, controls, and cost. You get the plan before migration starts.
Build
We deploy QA, CI/CD, OTA, and telemetry. The mobile delivery stack runs in your environment from day one.
Extend
Your team owns the stack long term. We stay on to extend it as delivery needs grow.
Why teams bet on Callstack
From billion-user apps to React Native core, this is why teams choose Callstack when they need to move fast and get it right.
10 years in React Native. Now shaping agentic engineering.
For a decade, we have helped define how teams ship with React Native. Now we are helping shape how they work with agents.
Founded in 2016 ·Backed by Viking Global Investors
React Foundation members. Core Contributors.
We are founding members of React Foundation and Core Contributors to React Native. You get direct access to people close to the decisions shaping the frameworks you use.
Open source since 2016. Our code runs in your app.
We contribute to React Native and maintain libraries across its ecosystem. Our code runs in apps used by millions of people every day.
39M+
Downloads / month67K+
GitHub stars300+
React Native commits100+ Enterprise clients with 7B+ users.
We work with teams shipping at real scale. You get a partner used to high-stakes products, not learning on your roadmap.
Agent Conf. The conference for the Agentic era.
The conference we built for the shift from writing code to orchestrating agents.
We are Codex Ambassadors.
We run meetups, workshops, and hands-on sessions that help teams learn Codex and apply it in real work.
10 years in React Native. Now shaping agentic engineering.
For a decade, we have helped define how teams ship with React Native. Now we are helping shape how they work with agents.
Founded in 2016 ·Backed by Viking Global Investors
React Foundation members. Core Contributors.
We are founding members of React Foundation and Core Contributors to React Native. You get direct access to people close to the decisions shaping the frameworks you use.
Open source since 2016. Our code runs in your app.
We contribute to React Native and maintain libraries across its ecosystem. Our code runs in apps used by millions of people every day.
39M+
Downloads / month67K+
GitHub stars300+
React Native commits100+ Enterprise clients with 7B+ users.
We work with teams shipping at real scale. You get a partner used to high-stakes products, not learning on your roadmap.
Agent Conf. The conference for the Agentic era.
The conference we built for the shift from writing code to orchestrating agents.
We are Codex Ambassadors.
We run meetups, workshops, and hands-on sessions that help teams learn Codex and apply it in real work.
Let’s find the right path for your product.
Whether you’re planning new work or unblocking an existing product, we’ll help you choose the right path forward.
What’s the benefit of using remote caching?
Remote caching allows builds to reuse compiled outputs across machines and environments, significantly speeding up pull request validations and release pipelines.
Can you help us build a release system that runs fully on our infrastructure?
Yes. We specialize in creating CI/CD pipelines, caching systems, and OTA flows that are fully self-hosted, giving you complete ownership of your mobile delivery process.
Can you automate app store submissions as part of CI/CD?
Yes. We integrate Fastlane, App Center, or EAS Submit to fully automate app signing, building, and store submission, shortening delivery time and reducing manual errors.
What’s the advantage of real-time release monitoring?
By integrating release monitoring and telemetry, you gain immediate visibility into regressions, crashes, and rollout health, allowing faster reaction and safer deployments.
How do you coordinate multiple teams shipping in parallel?
We implement structured release tracks, environment branching strategies, and staging automation, allowing different teams to ship features independently without delays or conflicts.
How do OTA updates and rollbacks work without a third-party provider?
We set up self-hosted over-the-air updates with staged rollouts, rollback, and secure delivery, all running on your infrastructure. No third-party update provider is involved.
What is Rock, and can we audit and extend it?
Rock is our open-source framework at the core of the pipeline: a drop-in replacement for the React Native Community CLI that your team can audit and extend. It works whether you use Expo or bare React Native.
Does this add infrastructure cost?
No. We set up self-hosted CI/CD with build caching on your own infrastructure with no added infrastructure cost, and reusable artifacts cut the redundant builds that waste compute.
20x faster builds in a week.
Expo or bare React Native, we set up self-hosted CI/CD with build caching on your infra. No added infra cost.
Their engineers proved to be a crucial part of our mobile app relaunch project.
Open Source
Want to build it on your own?
We open-source the tools behind our delivery model.
Use them, fork them, or let us run them for you.
Insights
Worth your time, by engineers.
Unlocking Expo Updates in an Isolated Brownfield Architecture with SDK 55
How to Release a React Native App on the Meta Horizon Store
Caching React Native Builds on S3 and R2 With Rock
We’re Building a New React Native Framework
Ship OTA (Over-The-Air) When in an Emergency
Mastering Fastlane: Overcoming Challenges in Passing Build Properties to Native Layers
How Can Continuous Integration (CI) Improve Your React Native Apps?
Continuous Delivery - Integration for Everyone
