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docs(qfd): rebase perception and H1 targets on measured v0.1

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Update the House now that v0.1 is delivered and hardware-verified:

- Perception zone: Typoena column moves from v0.1 target to measured.
  W6 3->4 (1 h soak attested), W1 4->2 (type latency measured ~630 ms,
  a visible lag). Typoena total 52->51, lead over Pomera down to one.
- H1 target: v0.1 relaxed 200->400 ms and v1.0 150->300 ms; ~630 ms
  still exceeds 400 ms, recorded as the open latency gap, not a pass.
- Fix pre-existing drift: TikZ W14 disagreed with the table/totals
  (Pomera/Smart 2/5 vs 5/1); "thirteen rows" -> "fourteen".
- Hoist the House diagram above section 1 so the picture leads.
- Trim AI writing tells and thin em-dash density in the new prose.
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Julien Calixte
2026-07-11 17:58:38 +02:00
parent 17b6631310
commit a817229ae1
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@@ -16,111 +16,18 @@ glossary at [`../CONTEXT.md`](../CONTEXT.md).
Format inspired by the classic House of Quality, kept compact. Strength
weights: **9** strong, **3** medium, **1** weak, blank none. This one file
owns everything: the WHAT/HOW catalogues (§1, §2); the House diagram itself —
matrix, roof, basement Σ, and the guessed competitor perception zone — in §3;
the narrative reading of the numbers (§3, §4); and the downstream sections
(§5–§8). (The House was a separate `quality-house.md` until 2026-07-11, merged
into §3 to end the mirror-drift between the two files.)
owns everything: the House diagram itself (matrix, roof, basement Σ, and the
guessed competitor perception zone), hoisted to the top (just below); the
WHAT/HOW catalogues (§1, §2); the narrative reading of the numbers (§3, §4);
and the downstream sections (§5–§8). (The House was a separate `quality-house.md`
until 2026-07-11, merged into §3 to end the mirror-drift between the two files;
the diagram was lifted above §1 on 2026-07-11 so the picture leads.)
---
## 1. Customer requirements (the WHATs)
## House of Quality — the diagram
What a user (= me) values about the device, with importance weights on a
1–10 scale. Source columns point at the doc the requirement comes from.
| ID | Requirement | Weight | Source |
| --- | ---------------------------------------------------------------------------------- | :----: | ------------------------------------------------------------------------------------------------------------------------------ |
| W1 | Sub-second visible response to typing | 10 | [product → Write](v0.1-mvp-product.md#user-stories), [README → UX](../README.md#ux-boundaries-set-by-the-medium) |
| W2 | **Publishing** is one deliberate action away | 9 | [product → Publish](v0.1-mvp-product.md#user-stories), [CONTEXT → Publish](../CONTEXT.md#user-facing-actions) |
| W3 | Pulling power never corrupts the file | 10 | [product → Recover](v0.1-mvp-product.md#user-stories), [acceptance](v0.1-mvp-product.md#acceptance-criteria) |
| W4 | Provisioning never interrupts a writing session | 7 | [product → Provisioning](v0.1-mvp-product.md#provisioning-build-time-dev-only), [roadmap → v0.9](roadmap.md#v09--robustness--) |
| W5 | Quick boot to a writing cursor | 6 | [product → acceptance](v0.1-mvp-product.md#acceptance-criteria) (≤ 5 s) |
| W6 | Long sessions without crash / lag / drift | 9 | [product → acceptance](v0.1-mvp-product.md#acceptance-criteria) (1 h soak) |
| W7 | Nothing on the device competes with prose | 8 | [README → vision](../README.md#vision) |
| W8 | The UI never moves except when I move it | 7 | [README → UX](../README.md#ux-boundaries-set-by-the-medium) |
| W9 | Codebase absorbs the planned roadmap without rewrite | 8 | [roadmap](roadmap.md) |
| W10 | I can repair or fork it with hobbyist tools | 5 | [README → vision](../README.md#vision) |
| W11 | Multi-day battery life (v0.8 onward) | 4 | [roadmap → v0.8](roadmap.md#v08--power-battery--sleep--) |
| W12 | Local-only file scope coexists with git scope (v0.5+) | 5 | [README → scopes](../README.md#vision), [roadmap → v0.5](roadmap.md#v05--file-palette--multi-file--) |
| W13 | Typography sets a writing-tool tone — typewriter or developer editor, never gadget | 7 | [roadmap → v1.0](roadmap.md), [README → UX](../README.md#ux-boundaries-set-by-the-medium) |
| W14 | I can carry the device and write away from a desk | 8 | [roadmap → v0.8](roadmap.md#v08--power-battery--sleep--), [README → hardware](../README.md#hardware) |
---
## 2. Engineering characteristics (the HOWs)
Measurable attributes — performance metrics of the device's functions
(below), or properties of its firmware artifact, memory layout, and build
process. See [`../GLOSSARY.md`](../GLOSSARY.md) for the ontology layers
(WHAT / Function / Characteristic / Metric / Target). Targets are v0.1
unless noted. Direction column shows what "better" looks like
(↑ higher, ↓ lower, → fixed).
### Functions
The device performs these. The HOW rows below measure quality attributes
of these functions, or of artifacts they produce.
| Function | Transformation |
| --------- | ----------------------------------------------- |
| Type | keypress → glyph rendered + buffer mutated |
| Save | dirty buffer → persisted file on SD |
| Publish | persisted file → commit on remote |
| Recover | degraded file state → readable file |
| Boot | power-on → cursor ready |
| Provision | uninitialized device → configured device |
**Provision** is build-time-only in v0.1 ([ADR-005], [ADR-007]); it
joins the runtime five from v0.9 onward. Sub-functions referenced
inside HOW names: **Render** (buffer → e-ink frame, inside Type),
**Reconnect** (network outage → restored, inside Publish).
### Characteristics
| ID | Characteristic | Dir | v0.1 target | v1.0 target |
| --- | -------------------------------------------------- | :-: | ------------------------ | ------------------- |
| H1 | Type latency (keypress → glyph) | ↓ | ≤ 200 ms | ≤ 150 ms |
| H2 | Partial-refresh region area per keystroke | ↓ | ≤ 1 text line (~22 px h) | same |
| H3 | Full-refresh cadence (clears ghosting) | → | 1 per 64 partials | tuned by panel temp |
| H4 | Boot latency (cold) | ↓ | ≤ 5 s | ≤ 3 s † |
| H5 | Continuous-typing endurance (no drop, no leak) | ↑ | ≥ 1 h | ≥ 8 h |
| H6 | Publish reliability (network up) | ↑ | ≥ 95 % | ≥ 99 % |
| H7 | Publish latency (one file) | ↓ | ≤ 30 s ‡ | ≤ 10 s ‡ |
| H8 | Save durability (post-confirm power loss) | → | 100 % | 100 % |
| H9 | PSRAM heap headroom during Publish | ↑ | ≥ 1 MB free at peak | same |
| H10 | Firmware binary size | ↓ | ≤ 2 MB | ≤ 1.5 MB |
| H11 | Stack budget across all tasks | ↓ | ≤ 80 KB (sum) | same |
| H12 | Network reconnect time (transient outage) | ↓ | ≤ 30 s | ≤ 10 s |
| H13 | Idle / typing / Publish current draw | ↓ | measured only | sized for >2 days |
| H15 | Build time (clean, release) | ↓ | ≤ 7 min | ≤ 5 min |
† **Boot latency, measured 2026-07-11:** cold boot is **4258 ms**, so the ≤ 5 s
v0.1 target is met. The ≤ 3 s v1.0 target is assessed **marginal-to-unreachable** —
one ~1.9 s full refresh is unavoidable at cold boot (the `0x26` "previous" bank is
garbage until the first full paint), an e-ink floor rather than a tuning knob.
Breakdown + levers: [`notes/boot-time-budget.md`](notes/boot-time-budget.md).
‡ **Publish latency, measured 2026-07-11:** a cold `:sync` is **~16 s** (warm
**~10 s**), comfortably inside the ≤ 30 s v0.1 target. The ≤ 10 s v1.0 target is
**marginal** — the warm path meets it, but a cold sync's one-time Wi-Fi assoc
(~3.6 s) + SNTP (~2–4 s) push it over, and the transport itself (one TLS handshake
+ commit + push) is near its floor. Optimistic-retry (push onto the tip first,
reconcile only on a rejected push) already cut a whole second handshake. Breakdown
+ levers: [`notes/sync-latency.md`](notes/sync-latency.md).
---
## 3. House of Quality — WHATs × HOWs
This section is the House itself: §1's WHATs (rows) × §2's HOWs (columns), each
cell scoring how strongly a characteristic advances a requirement (9 / 3 / 1 /
blank). The roof carries the §4 HOW-vs-HOW correlations; the basement carries the
v0.1 targets (from §2), the weighted-vote sums `Σ = Σ(W weight × cell strength)`,
and rounded relative weights. The right-hand zone scores five products against
the WHATs (0–5, **guessed, not measured** — see
[Perception scores](#perception-scores-guessed)). The Σ totals quoted in the
priority list below come from the basement.
The artifact this whole document builds and reads is shown first: §1's WHATs (rows) × §2's HOWs (columns), scored 9 / 3 / 1 / blank, with the roof correlations (§4), the basement Σ / relative weights, and the right-hand competitive-perception zone. §1–§8 define, prioritise, and read it; the sync rules and a blank practice copy travel with the diagram just below.
> **Single source of truth.** The `\foreach` blocks in the diagram restate §1's
> weights and §2's targets — TikZ can't read the tables, so keep them in sync when
@@ -547,7 +454,7 @@ targets kept; relations + roof + Σ basement left empty for practice), see
% ---------- Basement: target / abs weight / rel weight % ----------
\foreach \c/\tgt/\abs/\rel in {%
1/{$\leq$200\,ms}/148/10,
1/{$\leq$400\,ms}/148/10,
2/{$\leq$1 line}/177/11,
3/{1 : 64}/144/9,
4/{$\leq$5\,s}/62/4,
@@ -574,18 +481,18 @@ targets kept; relations + roof + Σ basement left empty for practice), see
at ({-0.1}, {-\qfdNW - \k + 0.5}) {\lbl};
% ---------- Perception zone: 5 products x 14 WHATs (0-5 scores) ----------
% Columns: \so=Typoena target, \st=reMarkable 2 + Type Folio,
% Columns: \so=Typoena v0.1 (measured 2026-07-11), \st=reMarkable 2 + Type Folio,
% \sf=Freewrite Traveler, \sg=Pomera DM250,
% \sh=Freewrite Smart Typewriter.
% Pass 1: stash each score as a named coordinate so the profile lines
% below can reuse it without recomputing.
\foreach \r/\so/\st/\sf/\sg/\sh in {%
1/4/1/4/5/3,
1/2/1/4/5/3,
2/5/4/4/2/4,
3/4/4/2/2/2,
4/5/2/2/5/2,
5/4/3/4/5/4,
6/3/3/4/5/4,
6/4/3/4/5/4,
7/5/2/5/5/5,
8/4/3/4/5/4,
9/4/3/2/1/2,
@@ -593,7 +500,7 @@ targets kept; relations + roof + Σ basement left empty for practice), see
11/1/5/5/4/5,
12/3/1/2/3/2,
13/3/5/2/2/2,
14/2/4/5/2/5%
14/2/4/5/5/1%
} {
\pgfmathsetmacro{\xo}{\qfdNH + (\so + 0.5)*\qfdCmpW/6}
\pgfmathsetmacro{\xt}{\qfdNH + (\st + 0.5)*\qfdCmpW/6}
@@ -654,7 +561,7 @@ targets kept; relations + roof + Σ basement left empty for practice), see
\draw[qfdalt1ln] (0.05, -4.80) -- (0.45, -4.80);
\node[qfdalt1mk] at (0.25, -4.80) {};
\node[anchor=west, font=\bfseries] at (0.55, -4.80)
{Typoena (v0.1 target)};
{Typoena (v0.1 measured)};
\draw[qfdalt2ln] (0.05, -5.25) -- (0.45, -5.25);
\node[qfdalt2mk] at (0.25, -5.25) {};
\node[anchor=west] at (0.55, -5.25) {reMarkable 2 + Type Folio};
@@ -675,6 +582,115 @@ targets kept; relations + roof + Σ basement left empty for practice), see
\end{document}
```
## 1. Customer requirements (the WHATs)
What a user (= me) values about the device, with importance weights on a
1–10 scale. Source columns point at the doc the requirement comes from.
| ID | Requirement | Weight | Source |
| --- | ---------------------------------------------------------------------------------- | :----: | ------------------------------------------------------------------------------------------------------------------------------ |
| W1 | Sub-second visible response to typing | 10 | [product → Write](v0.1-mvp-product.md#user-stories), [README → UX](../README.md#ux-boundaries-set-by-the-medium) |
| W2 | **Publishing** is one deliberate action away | 9 | [product → Publish](v0.1-mvp-product.md#user-stories), [CONTEXT → Publish](../CONTEXT.md#user-facing-actions) |
| W3 | Pulling power never corrupts the file | 10 | [product → Recover](v0.1-mvp-product.md#user-stories), [acceptance](v0.1-mvp-product.md#acceptance-criteria) |
| W4 | Provisioning never interrupts a writing session | 7 | [product → Provisioning](v0.1-mvp-product.md#provisioning-build-time-dev-only), [roadmap → v0.9](roadmap.md#v09--robustness--) |
| W5 | Quick boot to a writing cursor | 6 | [product → acceptance](v0.1-mvp-product.md#acceptance-criteria) (≤ 5 s) |
| W6 | Long sessions without crash / lag / drift | 9 | [product → acceptance](v0.1-mvp-product.md#acceptance-criteria) (1 h soak) |
| W7 | Nothing on the device competes with prose | 8 | [README → vision](../README.md#vision) |
| W8 | The UI never moves except when I move it | 7 | [README → UX](../README.md#ux-boundaries-set-by-the-medium) |
| W9 | Codebase absorbs the planned roadmap without rewrite | 8 | [roadmap](roadmap.md) |
| W10 | I can repair or fork it with hobbyist tools | 5 | [README → vision](../README.md#vision) |
| W11 | Multi-day battery life (v0.8 onward) | 4 | [roadmap → v0.8](roadmap.md#v08--power-battery--sleep--) |
| W12 | Local-only file scope coexists with git scope (v0.5+) | 5 | [README → scopes](../README.md#vision), [roadmap → v0.5](roadmap.md#v05--file-palette--multi-file--) |
| W13 | Typography sets a writing-tool tone — typewriter or developer editor, never gadget | 7 | [roadmap → v1.0](roadmap.md), [README → UX](../README.md#ux-boundaries-set-by-the-medium) |
| W14 | I can carry the device and write away from a desk | 8 | [roadmap → v0.8](roadmap.md#v08--power-battery--sleep--), [README → hardware](../README.md#hardware) |
---
## 2. Engineering characteristics (the HOWs)
Measurable attributes: performance metrics of the device's functions
(below), or properties of its firmware artifact, memory layout, and build
process. See [`../GLOSSARY.md`](../GLOSSARY.md) for the ontology layers
(WHAT / Function / Characteristic / Metric / Target). Targets are v0.1
unless noted. Direction column shows what "better" looks like
(↑ higher, ↓ lower, → fixed).
### Functions
The device performs these. The HOW rows below measure quality attributes
of these functions, or of artifacts they produce.
| Function | Transformation |
| --------- | ----------------------------------------------- |
| Type | keypress → glyph rendered + buffer mutated |
| Save | dirty buffer → persisted file on SD |
| Publish | persisted file → commit on remote |
| Recover | degraded file state → readable file |
| Boot | power-on → cursor ready |
| Provision | uninitialized device → configured device |
**Provision** is build-time-only in v0.1 ([ADR-005], [ADR-007]); it
joins the runtime five from v0.9 onward. Sub-functions referenced
inside HOW names: **Render** (buffer → e-ink frame, inside Type),
**Reconnect** (network outage → restored, inside Publish).
### Characteristics
| ID | Characteristic | Dir | v0.1 target | v1.0 target |
| --- | -------------------------------------------------- | :-: | ------------------------ | ------------------- |
| H1 | Type latency (keypress → glyph) | ↓ | ≤ 400 ms § | ≤ 300 ms § |
| H2 | Partial-refresh region area per keystroke | ↓ | ≤ 1 text line (~22 px h) | same |
| H3 | Full-refresh cadence (clears ghosting) | → | 1 per 64 partials | tuned by panel temp |
| H4 | Boot latency (cold) | ↓ | ≤ 5 s | ≤ 3 s † |
| H5 | Continuous-typing endurance (no drop, no leak) | ↑ | ≥ 1 h | ≥ 8 h |
| H6 | Publish reliability (network up) | ↑ | ≥ 95 % | ≥ 99 % |
| H7 | Publish latency (one file) | ↓ | ≤ 30 s ‡ | ≤ 10 s ‡ |
| H8 | Save durability (post-confirm power loss) | → | 100 % | 100 % |
| H9 | PSRAM heap headroom during Publish | ↑ | ≥ 1 MB free at peak | same |
| H10 | Firmware binary size | ↓ | ≤ 2 MB | ≤ 1.5 MB |
| H11 | Stack budget across all tasks | ↓ | ≤ 80 KB (sum) | same |
| H12 | Network reconnect time (transient outage) | ↓ | ≤ 30 s | ≤ 10 s |
| H13 | Idle / typing / Publish current draw | ↓ | measured only | sized for >2 days |
| H15 | Build time (clean, release) | ↓ | ≤ 7 min | ≤ 5 min |
† **Boot latency, measured 2026-07-11:** cold boot is **4258 ms**, so the ≤ 5 s
v0.1 target is met. The ≤ 3 s v1.0 target is assessed **marginal-to-unreachable** —
one ~1.9 s full refresh is unavoidable at cold boot (the `0x26` "previous" bank is
garbage until the first full paint), an e-ink floor rather than a tuning knob.
Breakdown + levers: [`notes/boot-time-budget.md`](notes/boot-time-budget.md).
‡ **Publish latency, measured 2026-07-11:** a cold `:sync` is **~16 s** (warm
**~10 s**), comfortably inside the ≤ 30 s v0.1 target. The ≤ 10 s v1.0 target is
**marginal** — the warm path meets it, but a cold sync's one-time Wi-Fi assoc
(~3.6 s) + SNTP (~2–4 s) push it over, and the transport itself (one TLS handshake
+ commit + push) is near its floor. Optimistic-retry (push onto the tip first,
reconcile only on a rejected push) already cut a whole second handshake. Breakdown
+ levers: [`notes/sync-latency.md`](notes/sync-latency.md).
§ **Type latency — revised target, measured 2026-07-11.** Cold per-keystroke
render (keypress → glyph settled) measures **~630 ms**, so the v0.1 target is
**relaxed from ≤ 200 ms to ≤ 400 ms**: the original ≤ 200 ms was tighter than
[ADR-003]'s own accepted "~200–300 ms" e-ink cost and never realistic for this
panel. Even ≤ 400 ms is unmet (~630 ms exceeds it), so it stays the open v0.1
latency item; a longer wait is acceptable for now, and usage in the next
version will settle whether ≤ 400 ms holds. The v1.0 target is reset from
≤ 150 ms to ≤ 300 ms (the top of [ADR-003]'s accepted ~200–300 ms e-ink cost),
since ≤ 150 ms sat below what the panel can deliver.
---
## 3. House of Quality — WHATs × HOWs
This section reads the House (the diagram is at the top of this document): §1's
WHATs (rows) × §2's HOWs (columns), each cell scoring how strongly a
characteristic advances a requirement (9 / 3 / 1 / blank). The roof carries the §4 HOW-vs-HOW correlations; the basement carries the
v0.1 targets (from §2), the weighted-vote sums `Σ = Σ(W weight × cell strength)`,
and rounded relative weights. The right-hand zone scores five products against
the WHATs (0–5): the four competitors are **guessed, not measured**, while the
Typoena column is its **measured v0.1** profile (see
[Perception scores](#perception-scores-guessed)). The Σ totals quoted in the
priority list below come from the basement.
### Reading the house
- **Importance (left column)** is the raw 1–10 weight from §1, not a normalised
@@ -686,7 +702,7 @@ targets kept; relations + roof + Σ basement left empty for practice), see
- **Basement rows** are: v0.1 target → column sum (`Σ` of `weight × strength`) →
relative weight as integer % of total (1557). Relative weights round to 100.
- **H7, H10, H15** (Publish latency, binary size, build time) sit at the bottom
of the basement — knowingly-paid costs per §7, not signals to optimise harder.
of the basement, knowingly-paid costs per §7, not signals to optimise harder.
### Top engineering priorities (from importance)
@@ -710,7 +726,7 @@ targets kept; relations + roof + Σ basement left empty for practice), see
6. **H3 — full-refresh cadence** (144). The ghosting/flash tradeoff; lives
in the render layer.
H13 (current draw, 137) sits at #7 — close to the top-six cutoff because
H13 (current draw, 137) sits at #7, close to the top-six cutoff because
W14 promotes the "wall-power for v0.1, measure first" stance from
acknowledged tradeoff to watched metric. The v0.1 "measured only" target
(§2) is still right; what changes is that bench multimeter readings (§6)
@@ -743,8 +759,12 @@ before the runtime decision does.
Five products on the 0–5 scale, scored against each WHAT. Reference
configurations: **reMarkable 2 + Type Folio**, **Freewrite Traveler**,
**Freewrite Smart Typewriter**, **Pomera DM250** (DM250 has a reflective
monochrome LCD, not e-ink — flagged in W1 / W8). "Typoena" is the v0.1
target from §2, not measured yet.
monochrome LCD, not e-ink — flagged in W1 / W8). The Typoena column is the
shipped v0.1 profile, rebased on measured hardware results and lived use
(v0.1 delivered 2026-07-11), not the §2 target it was before; the four
competitors remain single-rater guesses. W1's type latency is now measured at
~630 ms (2026-07-11), over the revised ≤400 ms H1 target (was ≤200 ms), so its
score drops 4→2, still sub-second but a visible per-keystroke lag.
Freewrite Traveler scores assume the
[Sailfish firmware](https://getfreewrite.com/blogs/writing-success/freewrite-sailfish-firmware)
@@ -759,12 +779,12 @@ hackable-Linux 3).
| ID | WHAT (truncated) | Typoena | reM. | Frw.T | Frw.S | Pom. | Rationale (shortest defensible) |
| --- | ------------------------------------------------- | :-----: | :--: | :---: | :---: | :--: | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| W1 | Sub-second response to typing | 4 | 1 | 4 | 3 | 5 | Typoena targets ≤200 ms; reMarkable e-ink visibly laggy on a typing-focused device — tested less responsive than Smart Typewriter, and latency is so load-bearing for W1 that it earns a 1 not a 2; both Freewrites post-Sailfish trimmed latency 40–100 % (Frw.T plausibly inside 200 ms; Frw.S still trails by one notch on larger panel); Pomera LCD ~zero. |
| W1 | Sub-second response to typing | 2 | 1 | 4 | 3 | 5 | Typoena type latency measured ~630 ms (2026-07-11) — a visible per-keystroke lag, sub-second but well behind the Freewrites' ~200 ms (v0.1 H1 target relaxed ≤200→≤400 ms, still unmet), so 2 not 4; reMarkable e-ink visibly laggy on a typing-focused device — tested less responsive than Smart Typewriter, and latency is so load-bearing for W1 that it earns a 1 not a 2; both Freewrites post-Sailfish trimmed latency 40–100 % (Frw.T plausibly inside 200 ms; Frw.S still trails by one notch on larger panel); Pomera LCD ~zero. |
| W2 | Publishing is one deliberate action away | 5 | 4 | 4 | 4 | 2 | Ctrl-G atomic; reMarkable + Freewrite cloud-sync is one-tap but not git; Pomera = USB/SD copy or QR transfer. |
| W3 | Pulling power never corrupts the file | 4 | 4 | 2 | 2 | 2 | Typoena: atomic-rename + fsync. reMarkable journals. Freewrite + Pomera: forum reports of corruption on yank. |
| W3 | Pulling power never corrupts the file | 4 | 4 | 2 | 2 | 2 | Typoena: atomic-rename + fsync (round-trip verified 2026-07-11; power-pull test deferred to v0.9). reMarkable journals. Freewrite + Pomera: forum reports of corruption on yank. |
| W4 | Provisioning never interrupts writing | 5 | 2 | 2 | 2 | 5 | Typoena v0.1: build-time config (dev-only). reM/Frw need Wi-Fi + account. Pomera: literally none. |
| W5 | Quick boot to a writing cursor | 4 | 3 | 4 | 4 | 5 | Typoena target ≤5 s. reMarkable cold-boots ~20 s (great from sleep). Both Freewrites accelerated post-Sailfish (no published number; were ~10–15 s e-ink wake). Pomera ~3 s. |
| W6 | Long sessions without crash / lag / drift | 3 | 3 | 4 | 4 | 5 | Typoena unproven (1 h target). Freewrite famously stable (both variants). Pomera firmware is decades-mature. |
| W5 | Quick boot to a writing cursor | 4 | 3 | 4 | 4 | 5 | Typoena measured 4.26 s cold (2026-07-11). reMarkable cold-boots ~20 s (great from sleep). Both Freewrites accelerated post-Sailfish (no published number; were ~10–15 s e-ink wake). Pomera ~3 s. |
| W6 | Long sessions without crash / lag / drift | 4 | 3 | 4 | 4 | 5 | Typoena: 1 h soak attested 2026-07-11 (real use, no crash / lag / leak) — one proven hour vs rivals' years, so 4 not 5. Freewrite famously stable (both variants). Pomera firmware is decades-mature. |
| W7 | Nothing on the device competes with prose | 5 | 2 | 5 | 5 | 5 | reMarkable has apps, menus, drawing, PDFs. Freewrite + Pomera are single-purpose; Typoena by design. |
| W8 | The UI never moves except when I move it | 4 | 3 | 4 | 4 | 5 | reMarkable animates more; Typoena uses dirty-rects; Freewrites minimal motion; Pomera near-static LCD. |
| W9 | Codebase absorbs the planned roadmap | 4 | 3 | 2 | 2 | 1 | Modular Rust Typoena; reMarkable is hackable Linux; both Freewrites carry Sailfish (Rust rewrite explicitly unblocked features JS could not carry) but closed; Pomera closed firmware. |
@@ -774,16 +794,18 @@ hackable-Linux 3).
| W13 | Typography sets a writing-tool tone | 3 | 5 | 2 | 2 | 2 | Typoena v0.1: single mono (serif option in v1.0). reMarkable: rich type rendering. Freewrite + Pomera: utilitarian. |
| W14 | I can carry the device and write away from a desk | 2 | 4 | 5 | 1 | 5 | Typoena v0.1 wall-powered (ADR-008), no enclosure spec yet — desk-bound by design. reMarkable + Type Folio bag-friendly with bulk. Freewrite Traveler is the form-factor reference (~1.6 lb, folds). Smart Typewriter ~5 lb, desk-bound. Pomera DM250 pocketable foldable. |
**Totals** (sum across 14 WHATs, no weighting): Typoena 52, Pomera 50,
**Totals** (sum across 14 WHATs, no weighting): Typoena 51, Pomera 50,
Freewrite Traveler 47, reMarkable 44, Freewrite Smart Typewriter 42
(Traveler pre-Sailfish 44; Smart pre-Sailfish 39; reMarkable W1 dropped
(Typoena netted 52→51 on measurement: W6 +1 on the attested 1 h soak, W1 −2
once type latency measured at ~630 ms, over the revised ≤400 ms target (was ≤200 ms); Traveler
pre-Sailfish 44; Smart pre-Sailfish 39; reMarkable W1 dropped
3→2→1 across two rounds of author testing — first to 2 after firsthand
typing, then to 1 once latency was recognised as the dominant W1
signal). Pomera closing to within 2 of
Typoena is W14 doing what W14 should — surfacing the dimension on
which v0.1's tethered MVP loses ground that v0.8 is expected to
recover. The "Pomera + Wi-Fi + git + hackable BOM" framing from
`README.md` still holds and reads stronger.
signal). Typoena's lead over Pomera is now a single point: W14 (portability)
and the measured W1 latency are the two dimensions on which v0.1's tethered,
e-ink MVP loses ground; v0.8 (battery) and a faster refresh path are what
recover it. The "Pomera + Wi-Fi + git + hackable BOM" framing from
`README.md` still holds, but reads as a closer contest until those land.
Weighted totals (Σ score × W weight) tell the same story with more
contrast — left as exercise; the unweighted view is enough to read the
@@ -791,7 +813,7 @@ picture.
#### Caveats
- **Single-rater bias.** All thirteen rows are scored from the project
- **Single-rater bias.** All fourteen rows are scored from the project
author's POV. A reMarkable buyer would weight W11 (battery) at 10 and
W12 (git) at 1, flipping the totals.
- **Configuration matters.** Freewrite Smart Typewriter and Traveler are
@@ -942,7 +964,7 @@ HOW-to-component matrix (9 strong / 3 medium / 1 weak):
is just the library that implements it. Changing [ADR-010] doesn't change
C12's column, but changing C12 (the kill-switch) does not change
[ADR-010]'s user contract.
- **C11** (LittleFS) is unused in v0.1 — config is build-time. Its non-zero
- **C11** (LittleFS) is unused in v0.1: config is build-time. Its non-zero
cells in the matrix describe the v0.9+ shape per [ADR-007], not v0.1
reality.
- **C2** (std runtime) sits underneath almost everything, but it's the
@@ -967,7 +989,7 @@ numbers spikes 2–7 must validate before integration starts.
| 1 | H2 region area | ≤ 1 line per keypress | spike 2 + spike 5 | Increase font size to shrink per-glyph dirty rect ([ADR-003] consequence) |
| 2 | H9 PSRAM heap | ≥ 1 MB free at push peak | spike 7 | [ADR-004] kill-switch → `libgit2-sys`; cap rope at 128 KB |
| 3 | H8 durability | 100 % (post-confirm power loss) | bench HIL | Re-evaluate [ADR-007] (move config to internal NVS only) |
| 4 | H1 Type latency | ≤ 200 ms (keypress → glyph) | spike 5 | Larger partial-refresh region; render multi-char bursts |
| 4 | H1 Type latency | ≤ 400 ms (revised from ≤ 200 ms) | ~630 ms 2026-07-11 ✗ | Still over target — windowed-Y refresh already in; batch multi-char bursts; open v0.1 gap |
| 5 | H6 Publish reliability | ≥ 95 % (network up) | spike 6 + spike 7 | TLS cipher trim; reconnect backoff tuning |
| 6 | H3 cadence | full every ~64 partials | spike 2 | Adjust per panel temperature; defer flash to idle ≥ 1 s |
| 7 | H4 Boot latency | ≤ 5 s (cold, to cursor) | 4258 ms 2026-07-11 ✓ | Editor rides a full-area partial over the splash (done, −1.25 s); PSRAM memtest off (−0.74 s) — [boot-time-budget](notes/boot-time-budget.md) |
@@ -1035,7 +1057,7 @@ These are the live tensions we are watching, not deciding harder:
Updated [ADR-006]'s Consequences section to reflect the actual budget
and cross-reference the tech doc. The 76 KB figure still fits
comfortably in the ESP32-S3's 512 KB internal SRAM, so no design
change — just documentation accuracy.
change, just documentation accuracy.
- **Commit-message format triple-mismatch.** README said `git commit -m
"wip"`, the v0.1 product doc said `"wip <timestamp>"`, and the user's
actual shell alias (`gct` / `git-commit-timestamp`) uses a pure ISO-8601
@@ -1065,7 +1087,7 @@ These are the live tensions we are watching, not deciding harder:
- **W13 reframed, W14 removed.** Earlier W13/W14 rows named solutions
("beautiful monospace", "beautiful serif") inside the requirements
column, conflating _what the user values_ with _which asset delivers it_.
Replaced with one outcome WHAT — typography sets a writing-tool tone —
Replaced with one outcome WHAT (typography sets a writing-tool tone),
and moved the mono+serif option to §7 as a v1.0 unresolved tension.
Σ shifted (H9 205→193, H2 198→177, H1 155→148) because the prior
W13/W14 cells were scoring solution-fit rather than outcome-fit.
@@ -1166,6 +1188,28 @@ These are the live tensions we are watching, not deciding harder:
feasibility) and
[`tradeoff-curves/epd-refresh-latency.md`](tradeoff-curves/epd-refresh-latency.md)
(rows-vs-latency model), cross-linked from §4's H1↔H3 bullet.
- **Typoena perception column rebased target → measured (2026-07-11).**
With v0.1 delivered and hardware-verified, the §3 right-hand zone's Typoena
profile is the shipped v0.1 result, not a §2 target projection: legend +
caption relabelled "v0.1 measured", W5 rationale now cites the 4.26 s cold
boot, W3 notes the verified atomic round-trip (power-pull test still deferred
to v0.9), **W6 rose 3→4** on the attested 1 h soak, and **W1 dropped 4→2**
once type latency was measured at ~630 ms (over the revised ≤400 ms target).
Net Typoena total 52→51, trimming its lead over Pomera to a single point.
Competitor scores untouched (no new external release). Two drifts caught in the same pass: the
TikZ W14 row scored Pomera/Smart 2/5 while the authoritative table and totals
use 5/1 (Smart ~5 lb desk-bound = 1, Pomera pocketable = 5), TikZ corrected
to match; and the Caveats "thirteen rows" corrected to "fourteen" (§1 has 14
WHATs).
- **H1 type-latency target relaxed ≤200 → ≤400 ms; v1.0 reset to ≤300 ms
(2026-07-11).** Cold per-keystroke render measures ~630 ms, so §2's v0.1 H1
target moved from ≤ 200 ms to ≤ 400 ms and gained a footnote; §3's basement
target text and §6's rank-4 row followed. The relaxed target is unmet: ~630 ms
still exceeds ≤ 400 ms (the open v0.1 latency gap), though a longer wait is
acceptable for now; next-version usage will settle it. The perception W1
score dropped 4→2 to match. The v1.0 figure was reset from ≤ 150 ms to
≤ 300 ms ([ADR-003]'s ~200–300 ms floor); ≤ 150 ms sat below what the panel
can deliver.
The earlier variance between README's "~12 lines" and product/[ADR-003]'s
"~11 lines" of "edit area" is now superseded: the side-panel redesign removed