Notes from the Tennnis studio. Build logs, playbooks, pricing and launch numbers.https://tennnis.noenhttps://tennnis.no/blog/what-is-on-device-aihttps://tennnis.no/blog/what-is-on-device-aiOn-device AI runs on your phone's own chip, so what you type or photograph never leaves it. Since iOS 27, "built with Apple's AI" no longer guarantees that. How to tell, and how to choose.Wed, 07 Oct 2026 00:00:00 GMTPlaybookhttps://tennnis.no/blog/open-source-a-side-projecthttps://tennnis.no/blog/open-source-a-side-projectBefore you open source a side project you built for yourself, run it on a machine that has never seen your setup. What open sourcing Agency took, from logs and signing to a Linux port.Tue, 06 Oct 2026 00:00:00 GMTBuild loghttps://tennnis.no/blog/run-multiple-ai-coding-agentshttps://tennnis.no/blog/run-multiple-ai-coding-agentsGive every agent its own git worktree and branch, then review each diff before you merge. The steps by hand, what Claude Code, Codex and Cursor automate, and the traps.Tue, 06 Oct 2026 00:00:00 GMTPlaybookhttps://tennnis.no/blog/eight-days-of-tmuxhttps://tennnis.no/blog/eight-days-of-tmuxWe ran Claude Code and Codex inside tmux for eight days. Dead panes and blank reattaches pushed us to a small Rust daemon that keeps every agent's screen.Fri, 04 Sep 2026 00:00:00 GMTBuild loghttps://tennnis.no/blog/senba-hands-back-proof-not-praisehttps://tennnis.no/blog/senba-hands-back-proof-not-praiseApple's on-device model is good with words and bad with facts. In Senba, code picks the facts, the model writes the words, and a validator checks every line.Fri, 28 Aug 2026 00:00:00 GMTBuild loghttps://tennnis.no/blog/a-dumb-phone-app-is-just-a-menuhttps://tennnis.no/blog/a-dumb-phone-app-is-just-a-menuApple rejects home screen replacements, so every dumb phone app for iPhone is a text-list widget that opens Spotify. What a real one has to own instead.Wed, 19 Aug 2026 00:00:00 GMTBuild loghttps://tennnis.no/blog/how-we-scope-a-fixed-price-projecthttps://tennnis.no/blog/how-we-scope-a-fixed-price-projectA fixed-price app quote that holds lists every screen and state, prices each line, adds a change budget, and moves anything unknown into paid discovery.Sun, 12 Jul 2026 00:00:00 GMTPlaybook