RFC: Android Kotlin → Rust/Tauri 2 migration by hyperpolymath · Pull Request #96 · hyperpolymath/neurophone

hyperpolymath · 2026-06-02T09:24:33Z

Status

DRAFT — RFC only. Awaiting owner review BEFORE any bulk conversion.
No Kotlin deleted, no Tauri scaffolding generated, no behaviour change.

Why

android/ ships 7 Kotlin files + 3 *.gradle.kts files, all banned by the
Hyperpolymath language policy. This keeps two CI gates permanently red:

Check for Banned Languages (.github/workflows/language-policy.yml:87-94)
governance / Language / package anti-pattern policy (estate-wide)

What this PR contains

A single document — docs/migrations/RFC-ANDROID-KOTLIN-TO-RUST.adoc — that:

Inventories every Kotlin component (LoC, role, replacement).
Names the unavoidable JVM-bytecode surface — Activity, Service,
BroadcastReceiver, AppWidgetProvider — that Android instantiates by
class name and that pure Rust cannot satisfy.
Proposes Path A (Tauri 2-generated Java shims under
src-tauri/gen/android/, with a CI exemption analogous to
node_modules/) and explicitly rejects Paths B (drop the widget) and
C (JVM bytecode emission from Rust).
Lays out a 9-PR landing sequence with explicit dependencies.

Component mapping (one-line summary)

Kotlin file	Replacement
`MainActivity.kt`	Tauri 2 `MainActivity` + AffineScript webview UI
`NeurophoneService.kt`	Generated Java `Service` shim → JNI into Rust
`BootReceiver.kt`	Generated Java `BroadcastReceiver` shim → JNI
`NativeLib.kt`	Delete; lives in `crates/neurophone-android/src/lib.rs`
`NeurophoneAppWidget.kt`	Generated Java `AppWidgetProvider` shim
`NeurophoneWidgetActions.kt`	Generated Java `BroadcastReceiver` shim
`NeurophoneWidgetConfigureActivity.kt`	Generated Java `Activity` shim (or drop)
`*.gradle.kts`	Tauri-generated under `gen/android/`

Sub-PR sequence (proposed)

This PR — RFC only.
CI exemption for src-tauri/gen/android/ (coordinated with hyperpolymath/standards).
cargo tauri android init scaffolding.
Port NativeLib Kotlin → crates/neurophone-android/src/lib.rs.
Port NeurophoneService.
Port BootReceiver.
Port widget triple (provider / actions / configure).
AffineScript UI (replaces activity_main.xml).
Delete legacy android/ tree — both CI gates green.

PRs 2 & 3 sequenced; 4–7 parallelizable after 3; 8 needs 4; 9 gated on all.

Open questions for owner

Tauri vs Dioxus — RFC recommends Tauri 2; confirm.
CI exemption scope — OK to exempt src-tauri/gen/android/?
Estate governance — who owns the cross-repo anti-pattern policy
callable in hyperpolymath/standards?
Widget config sacrifice — acceptable to drop the configure activity?
Hardware test plan — Oppo Reno 13 vs emulator + Termux?
SPDX clash — repo files use PMPL-1.0-or-later, local hook expects
MPL-2.0. Pick canonical before sub-PRs.

Constraints honoured in this PR

PMPL header attempted but blocked by local hook → MPL-2.0 used + clash
flagged in the RFC's "Open questions". See open question chore(deps): update reqwest requirement from 0.11 to 0.12 #6.
No new GitHub Actions added.
No Deno/npm/TypeScript changes.

Test plan

RFC document renders as AsciiDoc.
Owner reviews component mapping for completeness.
Owner picks Tauri vs Dioxus, confirms CI-exemption plan, resolves SPDX clash.
Sub-PR Add STATE.scm project checkpoint file #2 (CI exemption) opens once approved.

🤖 Generated with Claude Code

Draft RFC for owner review before any bulk conversion. Maps each of the 7 Kotlin files + 3 *.gradle.kts to a Rust/Tauri replacement, calls out the unavoidable JVM-bytecode surface (Service / BroadcastReceiver / AppWidgetProvider), and proposes a 9-PR landing sequence gated on CI-exemption coordination for Tauri-generated Java shims under src-tauri/gen/android/. No Kotlin deleted, no Tauri scaffolding generated — pure planning artefact. Both banned-language CI gates remain red until the sequenced sub-PRs land in order. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

hyperpolymath · 2026-06-02T09:43:54Z

Replaced by PR on chore/gossamer-migration-rfc — owner corrected the migration target from Tauri to Gossamer; rewriting under the right branch name.

hyperpolymath · 2026-06-02T09:49:25Z

Two owner decisions for this RFC are now settled — please update the doc accordingly before any sub-PRs:

Framework: gossamer, not Tauri/Dioxus. The estate is standardising on hyperpolymath/gossamer — its own resource-safe Tauri/Electron replacement (Idris2 + Zig, Ephapax linear types), which already targets mobile (Phase 5: iOS/Android). Open question Welcome to neurophone Discussions! #1 resolves to gossamer; the migration target (and the "generated Java shim under src-tauri/gen/android/" plan) should be re-expressed in gossamer's terms, coordinating with the gossamer repo on its Android path.
SPDX clash (open question chore(deps): update reqwest requirement from 0.11 to 0.12 #6): canonical is MPL-2.0. The repo has been reverted to SPDX-License-Identifier: MPL-2.0 uniformly (PMPL was a wrong turn). Use MPL-2.0 headers; no clash remains.

(Tracked on the neurophone side as #83, which now names gossamer.)

Generated by Claude Code

## Status **DRAFT — RFC only. Awaiting owner review BEFORE any bulk conversion.** No Kotlin deleted, no Gossamer scaffolding generated, no behaviour change. Supersedes #96 (was titled "Tauri 2" — owner correction: Gossamer is the estate target). ## Why `android/` ships 7 Kotlin files + 3 `*.gradle.kts` files, all banned by the Hyperpolymath language policy. Two CI gates permanently red: - `Check for Banned Languages` (`.github/workflows/language-policy.yml:87-94`) - `governance / Language / package anti-pattern policy` (estate-wide) ## What this PR contains A single document — `docs/migrations/RFC-ANDROID-KOTLIN-TO-RUST.adoc` — mapping every Kotlin component to its Gossamer replacement and proposing a 9-PR landing sequence. ## Component mapping (one-line summary) | Kotlin file | Replacement | |---|---| | `MainActivity.kt` | `NeurophoneMainActivity extends GossamerActivity` | | `NeurophoneService.kt` | Hand-written Java `Service` shim → JNI into Rust | | `BootReceiver.kt` | Hand-written Java `BroadcastReceiver` shim → JNI | | `NativeLib.kt` | Delete; lives in `crates/neurophone-android/src/lib.rs` | | `NeurophoneAppWidget.kt` | Hand-written Java `AppWidgetProvider` shim | | `NeurophoneWidgetActions.kt` | Hand-written Java `BroadcastReceiver` shim | | `NeurophoneWidgetConfigureActivity.kt` | Java `Activity` shim (or drop) | | `*.gradle.kts` | Groovy `*.gradle` (matches Gossamer upstream) | ## Key structural finding **Gossamer Android is webview-only today.** ROADMAP Phase 3 (Mobile) lists Android as *Partially Implemented* — only `GossamerActivity` + `GossamerBridge` exist upstream. The 7 platform-integration surfaces neurophone needs (service, widget, receivers, sensors, intent dispatch, prefs, deep-links) have **no upstream Gossamer support and no open Gossamer issues**. **Recommendation:** build all 7 downstream in neurophone's own `android/` tree as small Java shims that JNI immediately into Rust. Don't block neurophone on Gossamer upstream PRs. Estimated total shim surface: < 250 LoC of Java vs. current 926 LoC of Kotlin. ## Estate precedent - `panll` migrated `src-tauri/` → `src-gossamer/` (commit `598d537`, ADR-0001 in `b935727`). Webview UI unchanged; swapped `tauri` crate for `gossamer-rs`, `tauri.conf.json` for `gossamer.conf.json`, `cargo tauri build` for `deno task build` invoking the `gossamer` CLI. - panll is **desktop only** — its migration did not exercise foreground service or home-screen widget surfaces; neurophone will be the first. ## Sub-PR sequence (proposed) 1. **This PR** — RFC only. 2. CI exemption for `android/**/*.java` (coordinated with `hyperpolymath/standards`). 3. Gossamer scaffolding: `gossamer-rs` workspace dep, `gossamer.conf.json`, `NeurophoneMainActivity` Java shim loading placeholder HTML. 4. Port `NativeLib` Kotlin → `crates/neurophone-android/src/lib.rs`. 5. Port `NeurophoneService` → Java shim + Rust impl. 6. Port `BootReceiver`. 7. Port widget triple (provider / actions / configure). 8. AffineScript UI compiled to JS, loaded by Gossamer webview. 9. Delete legacy Kotlin `android/` tree — both CI gates green. PRs 2 & 3 sequenced; 4–7 parallelizable after 3; 8 needs 4; 9 gated on all. ## Open questions for owner 1. **CI exemption scope** — estate-wide via `hyperpolymath/standards` or neurophone-local? Linchpin question. 2. **Estate governance** — who owns the cross-repo anti-pattern policy callable in standards? 3. **Widget config sacrifice** — acceptable to drop the configure activity? 4. **Gradle DSL** — Groovy `*.gradle` (matches Gossamer upstream) or keep Kotlin `*.gradle.kts` under a separate exemption? 5. **Hardware test plan** — Oppo Reno 13 vs emulator + Termux? 6. **Upstream contribution** — build shims neurophone-local, or factor a `gossamer-android-services` companion as we go? ## Constraints honoured - All new files MPL-2.0 SPDX. - No new GitHub Actions added. - No Deno/npm/TypeScript changes. ## Test plan - [x] RFC document renders as AsciiDoc. - [ ] Owner reviews component mapping for completeness. - [ ] Owner picks CI-exemption scope (open Q1). - [ ] Owner resolves Gradle DSL choice (open Q4). - [ ] Sub-PR #2 (CI exemption) opens once approved. 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

hyperpolymath closed this Jun 2, 2026

hyperpolymath deleted the chore/tauri-migration-rfc branch June 2, 2026 09:43

hyperpolymath mentioned this pull request Jun 2, 2026

RFC: Android Kotlin → Rust/Gossamer migration #97

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build: migrate Kotlin/Gradle Android app to gossamer (clears banned-language CI) #83

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build(#83): widget triple → generated Java shims (AppWidgetProvider + actions + configure) #113

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RFC: Android Kotlin → Rust/Tauri 2 migration#96

RFC: Android Kotlin → Rust/Tauri 2 migration#96
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chore/tauri-migration-rfc

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hyperpolymath commented Jun 2, 2026

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What this PR contains

Component mapping (one-line summary)

Sub-PR sequence (proposed)

Open questions for owner

Constraints honoured in this PR

Test plan

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hyperpolymath commented Jun 2, 2026

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