Spotify shares lessons learned from implementing background coding agents for automated code migrations. The team evolved from open-source tools like Goose and Aider to building a custom agentic loop, eventually settling on Claude Code for handling complex, multi-file changes across thousands of repositories. Key insights include crafting effective prompts that describe desired end states rather than step-by-step instructions, stating preconditions clearly, using concrete examples, and limiting tool access to maintain predictability. The system successfully merged thousands of PRs by balancing prompt specificity with agent autonomy, though evaluation and feedback loops remain areas for improvement.
Table of contents
Early open source agentsRolling our own agentic loopEnter Claude CodeThe proof is in the promptThe right tools for the jobConclusionSort: