Apex is now publicly available. Explore Callstack’s coding model for React Native and Next.js, with API pricing, benchmarks, and self-hosting options.
Apex Is Now Generally Available: Agentic Coding Model for Mobile and Web, Specialized in React
Agentic Delivery
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Custom & Private Models
Use the right AI model, locally or in the cloud.
Tell us where hosted models fall short for your team today. We'll come back with the right approach for your data and workload, and what the rollout path looks like.
- Keep sensitive data off third-party systems
- Get better output from the model
- Choose where the model runs
Custom & Private Models
Use Cases
On-Premise LLM Deployment
LLM Fine-Tuning
Model Evaluation

Backed by Viking Global
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ISO 27001
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React Foundation
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100+ Enterprise Clients
·
Used by 39M+ Developers
·
7B+ active clients users
·
Backed by Viking Global
·
ISO 27001
·
React Foundation
·
100+ Enterprise Clients
·
Used by 39M+ Developers
·
7B+ active clients users
·
Backed by Viking Global
·
ISO 27001
·
React Foundation
·
100+ Enterprise Clients
·
Used by 20M+ Developers
·
7B+ active clients users
·
Backed by Viking Global
·
ISO 27001
·
React Foundation
·
100+ Enterprise Clients
·
Used by 20M+ Developers
·
7B+ active clients users
·
Insights
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