Architecture

Solipsist is built in Swift 6 with SwiftUI for macOS 26+.

Spatial Model

Settings → Sources (the account book)

┌──────────────────┬─────────────────────────────┬──────────────────┐
│ MAILBOXES        │ READING                     │ DRAWER           │
│ Source as        │ Message list + reading      │ Profile, page    │
│ account header   │ pane for the selected page  │ fields, options  │
└──────────────────┴─────────────────────────────┴──────────────────┘
Companion windows: Preview (full site) · Editor (boris-editor)

M2–M8 shipped a flatter cut (source list + tabbed play). M10 is the recut to the diagram above.

Engine Integration

BorisEngine actor manages single-process execution and signal handling (SIGTERM).
Contract models decode normative Boris JSON formats.
Coordinator maps UI verbs to engine invocations, reporting timings and problems in real-time.

Process boundaries

The subprocess boundary is a feature, not an accident:

The boris binary ships inside the app (arm64, zero runtime deps) and runs only as an isolated subprocess — crash isolation and cancellation without ever hosting Zig in-process.
Swift never reimplements compiler semantics. The JSON contracts (manifest, graph, completion, build-report, analysis reports) are the single source of truth; the app mirrors and renders them.
Diagnostics and exit codes are surfaced, never silently swallowed.

These boundaries are the architectural form of the Mission’s non-negotiables, and they are the reason the graph shown in the reading place is the real graph from graph.json — not a Swift reconstruction.