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Over time, more and more code goes untested, forcing teams to spend more time debugging painful bugs. We built an autonomous agent that closes that gap. It reads Rails source files, generates or improves RSpec tests, validates them against style rules and coverage targets, and runs inside a CI/CD pipeline with no human intervention. To operate on codebases at this scale, it runs in parallel: multiple instances working on different files simultaneously. RSpec through an agent's eyes Ruby is dynamically typed: there is no compilation step, so errors surface at runtime. For our agent, this means the only way to verify test syntax is to execute it. RSpec , the standard Rails testing framework, makes tests expressive and readable, but its domain-specific..."},"evidence_pages":[],"related_signals":[{"id":"6659c084-7b80-4fa6-9ddf-35bbee1732c0","url":"https://onlylabs.fyi/signals/6659c084-7b80-4fa6-9ddf-35bbee1732c0","source_url":"https://mistral.ai/news/more-control-over-connectors/","title":"Bringing more control over your connectors","context":null,"kind":{"key":"post_published","label":"Writing"},"org":{"slug":"mistral","name":"Mistral AI","category":"frontier-lab"},"occurred_at":"2026-06-24T12:00:30+00:00","first_seen_at":"2026-06-26T20:22:13.235771+00:00","date_source":"rss.item_date"},{"id":"7f0b69a8-ccc2-46e9-bbd6-b2d907c58ff5","url":"https://onlylabs.fyi/signals/7f0b69a8-ccc2-46e9-bbd6-b2d907c58ff5","source_url":"https://mistral.ai/news/ocr-4/","title":"Introducing Mistral OCR 4","context":null,"kind":{"key":"post_published","label":"Writing"},"org":{"slug":"mistral","name":"Mistral AI","category":"frontier-lab"},"occurred_at":"2026-06-23T12:00:48+00:00","first_seen_at":"2026-06-26T20:22:13.235771+00:00","date_source":"rss.item_date"},{"id":"1df2c218-6ea3-4713-8f08-2d94d8dc5a9f","url":"https://onlylabs.fyi/signals/1df2c218-6ea3-4713-8f08-2d94d8dc5a9f","source_url":"https://mistral.ai/news/ai-now-summit-2026/","title":"AI Now Summit 2026","context":null,"kind":{"key":"post_published","label":"Writing"},"org":{"slug":"mistral","name":"Mistral AI","category":"frontier-lab"},"occurred_at":"2026-05-28T12:00:20+00:00","first_seen_at":"2026-06-26T20:22:13.235771+00:00","date_source":"rss.item_date"},{"id":"cfee09c0-fede-4e0f-9246-4800c0dfdc28","url":"https://onlylabs.fyi/signals/cfee09c0-fede-4e0f-9246-4800c0dfdc28","source_url":"https://mistral.ai/news/vibe-agent/","title":"Vibe gets to work.","context":null,"kind":{"key":"post_published","label":"Writing"},"org":{"slug":"mistral","name":"Mistral AI","category":"frontier-lab"},"occurred_at":"2026-05-28T12:00:09+00:00","first_seen_at":"2026-06-26T20:22:13.235771+00:00","date_source":"rss.item_date"},{"id":"263b565b-b6bd-4920-bb61-3d24328998b5","url":"https://onlylabs.fyi/signals/263b565b-b6bd-4920-bb61-3d24328998b5","source_url":"https://mistral.ai/news/search-toolkit/","title":"Introducing Search Toolkit","context":null,"kind":{"key":"post_published","label":"Writing"},"org":{"slug":"mistral","name":"Mistral AI","category":"frontier-lab"},"occurred_at":"2026-05-28T11:42:21+00:00","first_seen_at":"2026-06-26T20:22:13.235771+00:00","date_source":"rss.item_date"},{"id":"4e8a5478-ca7d-4f96-a06c-43d53a3aa21b","url":"https://onlylabs.fyi/signals/4e8a5478-ca7d-4f96-a06c-43d53a3aa21b","source_url":"https://mistral.ai/news/introducing-physics-ai-at-mistral/","title":"Introducing physics AI at Mistral: the foundation for engineering acceleration.","context":null,"kind":{"key":"post_published","label":"Writing"},"org":{"slug":"mistral","name":"Mistral AI","category":"frontier-lab"},"occurred_at":"2026-05-27T12:00:55+00:00","first_seen_at":"2026-06-26T20:22:13.235771+00:00","date_source":"rss.item_date"}]}