--- title: "Custom Agents" description: "Teams get more from AI when agents take on repeatable engineering work. We set up internal agents and workflows so work can run in parallel and continue after a developer session ends." url: https://www.callstack.com/capabilities/custom-agents updated: 2026-11-06T10:07:25.286Z --- # Custom Agents Teams get more from AI when agents take on repeatable engineering work. We set up internal agents and workflows so work can run in parallel and continue after a developer session ends. _[Agentic Delivery](https://www.callstack.com/agentic-delivery) › Custom Agents_ **Put agents on recurring engineering work.** Teams get more from AI when agents take on repeatable engineering work. We set up internal agents and workflows so work can run in parallel and continue after a developer session ends. [Book consultation](https://www.callstack.com/contact) [Explore services](#services) Trusted by 100+ Enterprise clients Expensify · Ticketmaster · DirecTV · MLS · PWC · Evernote · AutoZone · MoMo · Dream11 · Rainbow · Futurewei · RIMAC · Hello Fresh · Haaretz · ForaTravel · CelcomDigi · Teamworks · Boats · Questrade · Dialogue Why build agents with Callstack ## Turn repeatable work into agents. We build internal agents around your standards, repos, and delivery systems so recurring work keeps moving after a developer session ends. Teams reduce manual review, testing, docs, and workflow steps. - **Keep work moving in parallel.** Agents continue repeatable engineering work beyond a single developer session. - **Cut the busywork around delivery.** Review, testing, documentation, and workflow steps need less manual effort. - **Turn team habits into tools.** Internal agents capture standards and workflows that would otherwise stay informal. - **Grow output without hiring linearly.** Teams can handle more work without matching every gain to headcount. Services ## Automate the work around delivery. ### Use Cases - [Code Review Agents](https://www.callstack.com/services/code-review-agents): Check PRs for regressions, missing tests, weak patterns, and team standards before human review. - [Upgrade Agents](https://www.callstack.com/services/upgrade-agents): Run framework, dependency, and React Native upgrade work with repeatable checks and migration steps. - [Maintenance Agents](https://www.callstack.com/services/maintenance-agents): Handle routine cleanup, dependency updates, deprecated APIs, and repo hygiene before they block delivery. - [Documentation Agents](https://www.callstack.com/services/documentation-agents): Keep technical docs, changelogs, release notes, and implementation notes aligned with code changes. - [CI/CD Automation Agents](https://www.callstack.com/services/ci-cd-automation-agents): Automate build checks, pipeline fixes, test reruns, release gates, and rollout steps across your delivery workflow. - [Internal Tool Agents](https://www.callstack.com/services/internal-tool-agents): Connect agents to tickets, repos, CI, Slack, Linear/Jira, and internal systems with scoped access and clear rules. Custom Agents ## Build agents for your delivery workflow. Show us your most repetitive workflows. We will build custom agents that handle the heavy lifting while your team focuses on high-impact work. [Build custom agents](https://www.callstack.com/contact) Scope → Build → Scale ## Build agents into repeatable workflows. ### Scope We select a product workflow, define where agents act, and agree the controls and success measures. - Workflow and owners defined - Baseline and controls agreed - Token budgets confirmed ### Build We connect context, agents, and verification to your tools, then run the workflow on your product backlog. - Running on your product backlog - Speed and quality measured - Business impact validated ### Scale We document the workflow, transfer ownership, and extend it across teams and products based on results. - Your team owns the workflow - Expand based on results - Full knowledge handover - 3x Delivery acceleration · 80% Effort executed by agents - Industry runs on our tooling · 50M+ OSS downloads / month - [3.7× Lower task cost vs Opus 5.5](https://apex.callstack.com) - [Built on Agent Device. · T3 · Shopify · Tester Army · Agent Device](https://agent-device.dev/) - React Foundation Founding Member · 300+ commits to React Native · Contributing since 2016 - 100+ Enterprise projects delivered - ISO 27001 certified Case studies ## What shipping at AI speed looks like ### [Building an Agentic SDLC for a Web Launch in Under One Month](https://www.callstack.com/case-studies/building-an-agentic-sdlc-for-a-web-launch-in-under-one-month) Agentic Delivery · Software Development **3x** estimated delivery acceleration 10 years of React Native → Now in your AI stack ## Build agents for your delivery workflow. Show us your most repetitive workflows. We will build custom agents that handle the heavy lifting while your team focuses on high-impact work. [Build custom agents](https://www.callstack.com/contact) Open Source ## Build with our open-source tools. We open-source the tools behind our delivery model. Use them, fork them, or let us run them for you. [Check All Tools](https://www.callstack.com/open-source) - [Agent Device](https://agent-device.dev/): CLI to control iOS and Android devices for AI agents (980.4K downloads/mo) - [Agent React DevTools](https://github.com/callstackincubator/agent-react-devtools): Gives AI agents access to React DevTools (251 stars) - [Agent Skills](https://github.com/callstackincubator/agent-skills): Callstack’s best practices on React Native performance optimization, upgrading, CI workflows, and brownfield migrations (1.7K stars) - [React Native AI](https://github.com/callstackincubator/ai): On-device LLM execution in React Native with Vercel AI SDK compatibility (227.7K downloads/mo) - [Skill Gym](https://incubator.callstack.com/skillgym/): Prove your agent skills work before you ship them (1.6K downloads/mo) - [React Native Evals](https://github.com/callstackincubator/evals): A benchmark suite for evaluating how coding models solve real React Native tasks (111 stars) Insights ## Worth your time, by engineers. [Explore Insights](https://www.callstack.com/insights) - [Beyond Coding Agents: Making ADLC Work Across Platforms](https://www.callstack.com/events/beyond-coding-agents-making-adlc-work-across-platforms) (Nov 16 · Talk): Mike Grabowski will explain how to close the full agentic development lifecycle across mobile, web, and native platforms. - [From Design to Shipped: A Modern App Development Meetup](https://www.callstack.com/events/from-design-to-shipped-a-modern-app-development-meetup) (Oct 22 · Meetup): Join Callstack, JetBrains, and Expo in Amsterdam on October 22 for talks on AI agents, UI development, and verification across web and mobile. - [MCP and Supervisor Agents in eBay's Monitoring Workflow With Leonel Candido da Silva](https://www.callstack.com/podcasts/mcp-and-supervisor-agents-in-ebays-monitoring-workflow-with-leonel-candido-da-silva) (Oct 13 · Podcast): Leonel Candido da Silva explains eBay's agentic monitoring workflow: specialized agents, MCP, PagerDuty reports, and plans to learn from past incidents. - [State Machines for AI Agents With David Khourshid](https://www.callstack.com/podcasts/state-machines-for-ai-agents-with-david-khourshid) (Oct 12 · Podcast): David Khourshid explains state machines for AI agents, human approval steps, tracing, and handling invalid model outputs in agent workflows. - [Inside Cursor, Colossus, and Grok Bot With Nick Miller](https://www.callstack.com/podcasts/inside-cursor-colossus-and-grok-bot-with-nick-miller) (Oct 12 · Podcast): Nick Miller explains Cursor's move to SpaceXAI, how Colossus changed model training, and the browser experience behind Grok Bot. - [Agent Conf](https://www.callstack.com/events/agent-conf) (Sep 17 · Conference): Join 500+ engineers in Warsaw Sept 17-18 2026 for Agent Conf. Learn agentic development, orchestration, and AI-driven workflows. - [Graph Agentic Coding Extends AI Workflows](https://www.callstack.com/events/how-graph-agentic-coding-extends-ai-workflows) (Aug 27 · Live Stream): How connected state, retrieval, memory, and verification carry coding agents across complex, multi-step workflows. Kewin Wereszczyński and Lech Kalinowski discuss the structures that let agents plan, retrieve context, use tools, and keep working across longer tasks. - [How We Built a React Native News Agent With Eve](https://www.callstack.com/events/build-a-react-native-news-agent-with-eve) (Jul 30 · Live Stream): See how we built and deployed an Eve agent that tracks React and React Native repositories, filters commit noise, and publishes daily Slack updates.