With the move to BYOS there is no TRMNL cloud to interpret a Liquid
template, so the application draws the screen itself.
The pipeline is satori (flexbox to SVG) then resvg (SVG to pixels) then
a hand-written 1-bit encoder. Chromium was the alternative and was
rejected: half a gigabyte and a real memory appetite in the runtime
image, for a screen of eight blocks. Playwright still handles the E2E
tests, in its own pinned image, never in the application one.
The payoff is testability. The layout is asserted on the element tree
and the geometry on the SVG text, so a rendering regression shows up as
a readable diff instead of a pixel comparison. The BMP and PNG encoders
are verified field by field against their specifications, including an
independent CRC-32 for the PNG: a device rejecting a malformed image is
expensive to debug from a shop window.
Two properties are pinned because the battery depends on them: the same
payload must produce byte-identical output, and changed hours must
produce different output. The filename handed to the device is a hash of
these bytes, and the firmware skips the redraw when it is unchanged.
The fonts are vendored into public/fonts and the logo into public/brand,
both committed. Rendering must not depend on an install tree, a CDN or
the network, or the bytes drift and the panel wakes for nothing.
`npm run screen:preview` writes a real 1-bit image plus a magnified view,
which is where clipping and thin strokes give themselves up. That is how
the week strip was caught clipping and condensed.
`npm run brand` rebuilds the assets: it locates the wordmark band in the
shop logo rather than hard-coding offsets a future revision would break,
and thresholds it with the panel's own encoder. sharp is a devDependency
used only there; nothing at runtime needs it.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012cSY9pVhZmJUKNN7wf1Myd
Model the whole domain: settings, the reference week, dated exceptions,
vacation periods, the public-holiday cache, display messages, the
translation cache, the audit log, and the device tables the BYOS server
needs (Device, DeviceLog, SyncState).
Two modelling decisions are load-bearing and documented in the schema:
- Opening times are wall-clock "HH:mm" strings in the shop timezone,
never instants. Nothing is stored in UTC, which turns the March and
October daylight-saving switches into non-events instead of edge cases.
- VacationPeriod is a source of truth, never expanded into
ScheduleException rows. The resolver reads it directly at priority
rank 2, so a holiday sync can never overwrite a manual exception and
editing a period leaves no orphans behind.
Device access tokens are stored only as SHA-256 digests, and the image
filename column holds a content hash: the firmware skips the redraw when
the filename is unchanged, which is where the battery life comes from.
Prisma 7 no longer accepts the connection URL in the schema file, so it
moves to prisma.config.ts with the pg driver adapter.
The dev Postgres service lands here rather than with the rest of the
Docker work, because the migration needs a database to run against.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012cSY9pVhZmJUKNN7wf1Myd
Set up the project skeleton for the ITA ITO opening-hours display admin:
Next.js 16 (App Router) with TypeScript in strict mode, Tailwind CSS 4,
Vitest, ESLint and a blocking CI workflow.
The design tokens are copied verbatim from the model_ita_ito project
(palette, Inter Variable + Source Serif 4, radii, dark theme) so the two
applications look like one family, as required by the spec.
ESLint is pinned to v9: eslint-config-next bundles a react plugin that
crashes on ESLint 10. The typed `consistent-type-imports` rule is left
out because `verbatimModuleSyntax` already enforces the same discipline
at compile time, without the cost of typed linting across the repo.
PLAN.md records the agreed architecture, including the decisions that
depart from the original spec — most importantly the move from BYOD to
a self-hosted BYOS server, which removes the TRMNL private plugin, the
Liquid template and the webhook entirely.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012cSY9pVhZmJUKNN7wf1Myd
vliaudatandClaude Opus 5