The most important investment in agentic coding velocity may have nothing to do with agents. Amplitude tripled its PR volume in six months. PR cycle time went from 5.2 hours to 44 minutes. Almost all of that came from fixing unglamorous infrastructure. 𝐂𝐈 𝐟𝐫𝐨𝐦 𝟑𝟎 𝐦𝐢𝐧𝐮𝐭𝐞𝐬 𝐭𝐨 𝟑: they swapped the JavaScript toolchain for native equivalents (tsc to tsgo, ESLint to oxlint, Prettier to oxfmt), moved to affected-only builds in Turborepo, and ran independent stages concurrently. Most tools got about 10x faster. 𝐅𝐮𝐥𝐥 𝐬𝐭𝐚𝐜𝐤 𝐮𝐩 𝐢𝐧 𝟐𝟖 𝐬𝐞𝐜𝐨𝐧𝐝𝐬: a custom CLI built on devbox starts every local service with one command, down from 3 minutes. 𝐕𝐚𝐥𝐢𝐝𝐚𝐭𝐢𝐨𝐧 𝐰𝐢𝐭𝐡 𝐧𝐨 𝐥𝐨𝐜𝐚𝐥 𝐬𝐞𝐭𝐮𝐩: add a label to a PR and get a frontend preview in under five minutes, or an ephemeral copy of the backend stack in the cloud. Once you have a full app stood up in 30 sec on every PR, testing and verification become much faster which decreases time to merge. 𝐑𝐞𝐯𝐢𝐞𝐰 𝐬𝐜𝐨𝐫𝐞𝐝 𝐛𝐲 𝐫𝐢𝐬𝐤: a model rates each code change on size, scope, test coverage, and API surface, and low-risk changes merge with no human. Cursor's Bugbot reviews every PR, and bug reports fell 55% even as PR volume tripled. Once CI dropped under five minutes, engineers stopped working locally. Remote is the new dev environment.