Anthropic has launched a preview of "dynamic workflow" for its terminal-based coding agent Claude Code (available via CLI, Desktop app, and VS Code extension). Designed for large-scale engineering challenges, the new workflow autonomously tackles cross-service bug tracking, refactoring hundreds of files, framework migrations, and pre-launch adversarial testing. The company says big migrations that used to take quarters can now be completed in days.
Instead of working through tasks linearly, the dynamic workflow flips the script. When you kick off a long-running task, the main agent writes its own orchestration script, splitting the goal into dozens or even hundreds of parallel sub-agents. Before merging code, the system assigns independent sub-agents to run adversarial tests from multiple angles, plus two rounds of code review (Reviewer Agents), until results converge. For jobs that run days or weeks, it supports incremental auto-archiving and resume from checkpoints.
Bun creator Jarred Sumner was the first to put it through its paces in an extreme refactoring project. In just 11 days, the dynamic workflow helped his team port Bun’s core from Zig to Rust, generating nearly 750,000 lines of Rust code — passing 99.8% of the original test suite. The dynamic workflow is now enabled by default for Max, Team, and API users. Developers can also turn on a new ultracode setting in the effort menu, which cranks up Claude Code's effort to maximum and lets the model decide when to kick off the dynamic workflow.