water park

Course 1 · start here

Fountain

Context

Intro

Eleven lessons take an Environment, an Agent and a Conversation from a single apply to a team you can talk to.

Four primitives opens the CLI and shows what those objects hold. The sandbox lifecycle follows one conversation from a fresh sandbox to suspension and back, and shows what a park keeps and what a destroy takes. The egress allowlist locks a sandbox down to named hosts, and a backend that cannot hold the lock gets refused. Credentials and vaults cover the two places secrets live and which one wins when both set the same key.

The team turns a conversation into a teammate with its own thread, and schedules puts a cron on top of it so the teammate speaks without being asked. Driving an agent from an app leaves the web UI behind and calls the same API from your own code.

Lessons 8 and 9 build the propose loop, first as something you trigger by hand, then as something that runs on its own from an event. Both are abstracted from real systems, Mend, Rounds and dns-desk, and the propose loop page is where that depth lives.

The self-hosted runner replaces the hosted sandbox with a container you run yourself, trading egress policy for a laptop you already trust. The course ends with the gate Fountain does not have, and what has to stand in for one.

11 lessons · about 4 h 10 min self-paced

  1. 1 Four primitives Fountain is made of four objects. · 20 min III F1
  2. 2 The sandbox lifecycle A conversation is a sandbox with a disk. · 15 min VII F2
  3. 3 The egress allowlist Limited networking denies all egress except the listed hosts. · 15 min VI F3
  4. 4 Credentials and vaults A vault binds one credential to one conversation. · 20 min VVIX F4
  5. 5 The team A teammate is one conversation on the team channel. · 10 min IX F5
  6. 6 Schedules A schedule runs a teammate with a prompt on a cron. · 10 min F6
  7. 7 Driving an agent from an app An app drives a teammate through fenced blocks and the team stream. · 45 min IX F7
  8. 8 The propose loop, interactive Mend and dns-desk run the propose loop with a person as the propose step. · 45 min IVVIIIXI F8
  9. 9 The propose loop, ambient Rounds runs the propose loop with nobody watching. · 30 min XIII F9
  10. 10 The self-hosted runner A self-hosted runner serves sandboxes from your own machine with no isolation. · 30 min VI F10
  11. 11 No approval gate in Fountain Fountain has no approval gate inside the agent loop. · 10 min VIII F11