Developer Experience for AI Agents

1 post · Nov 2025 – Jul 2026

What this trail covers

Modal's platform is evolving to enhance developer experience not just for human developers but also for AI coding agents. This involves applying core principles like fast feedback loops, programmatic access, actionable error messages, illustrative examples, unified infrastructure and logic, and consistent naming conventions. The goal is to accelerate the iterative process for both humans and agents, making the development lifecycle more efficient and less error-prone, particularly in AI development. Recent work has focused on applying these principles to agentic workflows and tooling.

All Modal trails

Jul 2026Devin Outposts on Modal | Modal BlogThis post introduces Devin Outposts, an integration that allows the AI software engineer Devin to run within user-controlled Modal sandboxes. It details the `modal-devin` open-source library and CLI for setting up these outposts, enabling Devin to leverage Modal's fast cold-starts, custom images, snapshotting, bursting mechanisms, and million-sandbox scale. The post highlights how this setup allows Devin to access specific toolchains and environments (e.g., GPU-backed sandboxes for serving config optimization) and provides code examples for the scheduler and session functions.
May 2026Introducing Claude Managed Agents with Modal Sandboxes | Modal BlogThis post announces the integration of Modal Sandboxes with Anthropic's Claude Managed Agents. It highlights how Modal Sandboxes provide a customizable, fast-starting, and secure execution environment for agent tool calls, complementing the managed agent loop provided by Anthropic. Key features emphasized include custom images, persistence options (volumes, snapshots), cost-efficient bursting, network security (short-lived connect tokens), and scalability (100,000+ concurrent sandboxes). The post also includes testimonials and examples from DoorDash and Blend, showcasing how this integration accelerates the development and deployment of production-ready AI agents.
Apr 2026Building with Modal and the OpenAI Agents SDK | Modal BlogThis post details the integration of the OpenAI Agents SDK with Modal Sandboxes, enabling agents to run in isolated environments with access to compute resources like GPUs. It introduces concepts like `SandboxAgent`, `ShellTool`, `Capability`, and `ModalSandboxSession` for building custom agent harnesses. The post also explores advanced techniques such as stateful sessions for memory accumulation, subagents for higher-order planning and context delegation, and a `SubAgentPool` for parallel execution and improved throughput. The `OrchestratorAgent` pattern is presented as a way to manage multiple subagents, with tools for spawning, invoking, and cleaning them up, and mechanisms for handling non-blocking execution and collecting results via `asyncio.Future`.
Mar 2026How Doppel eliminated ML infrastructure tax with Modal | Modal BlogThis post details how Doppel leveraged Modal to accelerate their ML training and inference workflows. For training, they moved from sequential experiments to parallel execution using `map()`, reducing feedback loops. They also integrated AI agents to automate mechanical steps in the experimentation loop, such as launching experiments and collecting metrics, by exposing Modal's CLI. For inference, they reduced build times by up to 10x through image layer caching and persistent volumes, simplified scaling with Modal's serverless architecture, and eliminated the need for manual HTTP service layers by invoking inference functions directly through Modal's abstractions.
Feb 2026How Ramp built a full context background coding agent on Modal | Modal BlogThis post details how Ramp built a full context background coding agent on Modal, leveraging Modal Sandboxes to provide full development environments with services like Postgres, Redis, and Temporal. It highlights the use of filesystem snapshots for near-instant sandbox startup (seconds), enabling the agent to match local development speed. Distributed primitives like Functions (cron jobs for repo cloning and dependency installation), Dicts (session locks and image metadata), and Queues (prompt routing) are used for scaling to hundreds of concurrent sessions and enabling multiplayer collaboration. The agent integrates with Ramp's internal tooling (Sentry, Datadog, GitHub, Slack, Buildkite) and supports visual verification via a VNC stack with Chromium.
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Nov 2025Agents need good developer experience tooThis post outlines Modal's framework for developer experience in the age of coding agents, emphasizing principles that benefit both humans and agents: tight feedback loops, programmatic access, actionable error messages, illustrative examples, unified infrastructure and logic, and consistent naming. It details how these principles, originally designed for human developers, translate effectively to agentic workflows, accelerating their ability to iterate and adapt.