local-dev

name	local-dev
description	Build, publish, and debug workflows for local development. Use when iterating on UI, debugging message sending, or testing on mobile devices.

Local Development

Build, publish, and debug workflows. For general Freenet local node management, contract publishing, and debugging patterns, see the local-dev skill in the freenet-agent-skills plugin.

Quick Start

Prerequisites

which freenet fdev dx
rustup target add wasm32-unknown-unknown

One-time setup

# 1. Build the web-container-tool (native, not cross-compiled)
cargo build --release -p web-container-tool

# 2. Build the web container contract WASM
cargo build --release --target wasm32-unknown-unknown -p web-container-contract

# 3. Generate test keys
mkdir -p test-contract
target/release/web-container-tool generate --output test-contract/test-keys.toml

# 4. Start an isolated test node (in a separate terminal or background)
#    Choose an appropriate log directory for your OS:
#      macOS:  ~/Library/Logs/freenet-test-node
#      Linux:  ~/.local/share/freenet-test-node/logs
LOG_DIR=~/Library/Logs/freenet-test-node   # adjust for your OS
mkdir -p "$LOG_DIR"
freenet network \
  --network-port 31338 \
  --ws-api-port 7510 \
  --ws-api-address 0.0.0.0 \
  --is-gateway \
  --skip-load-from-network \
  --data-dir ~/freenet-test-node/data \
  --public-network-address 127.0.0.1 \
  --log-dir "$LOG_DIR" \
  --log-level debug

Fast iteration script

# Full rebuild + republish (~15s):
./scripts/local-republish.sh

# Skip UI build if only repackaging (~2s):
./scripts/local-republish.sh --skip-build

# Target a different port:
./scripts/local-republish.sh --port 7509

The script outputs desktop and phone URLs after publishing. Use Playwright MCP tools to verify the result without opening a manual browser — see "Automated verification with Playwright MCP" below.

Build Commands

Individual components

cargo build --release --target wasm32-unknown-unknown -p room-contract  # Room contract WASM
cargo build --release --target wasm32-unknown-unknown -p chat-delegate   # Chat delegate WASM
cargo build --release --target wasm32-unknown-unknown -p web-container-contract  # Web container
(cd ui && dx build --release)                                            # UI (Dioxus)

Development mode

cargo make dev                     # dx serve with hot reload (localhost:8080)
cargo make dev-example             # dx serve with example data (no network needed)

Fast Iteration Loop

UI changes only (fastest)

# 1. Make your UI change in ui/src/
# 2. Rebuild + republish:
./scripts/local-republish.sh
# 3. Hard-refresh browser (Cmd+Shift+R / Ctrl+Shift+R)

Contract changes

# 1. Rebuild contract
cargo build --release --target wasm32-unknown-unknown -p room-contract

# 2. Copy to UI public dir (UI embeds contract WASM)
cp target/wasm32-unknown-unknown/release/room_contract.wasm ui/public/contracts/

# 3. Full rebuild + publish
./scripts/local-republish.sh

Delegate changes

# 1. Rebuild delegate (UI includes delegate via include_bytes!)
cargo build --release --target wasm32-unknown-unknown -p chat-delegate

# 2. Rebuild UI (picks up new delegate) + publish
./scripts/local-republish.sh

Manual publish

The cargo make publish tasks cross-compile the web-container-tool for x86_64-unknown-linux-gnu. On other platforms, use local-republish.sh or run the steps manually:

# 1. Build UI
(cd ui && dx build --release)

# 2. Compress
(cd target/dx/river-ui/release/web/public && tar -cJf ../../../../../webapp/webapp.tar.xz *)

# 3. Sign with test keys
target/release/web-container-tool sign \
  --input target/webapp/webapp.tar.xz \
  --output target/webapp/webapp-test.metadata \
  --parameters target/webapp/webapp-test.parameters \
  --key-file test-contract/test-keys.toml \
  --version $(( $(date +%s) / 60 ))

# 4. Publish
fdev --port 7510 execute put \
  --code target/wasm32-unknown-unknown/release/web_container_contract.wasm \
  --parameters target/webapp/webapp-test.parameters \
  contract \
  --webapp-archive target/webapp/webapp.tar.xz \
  --webapp-metadata target/webapp/webapp-test.metadata

Debugging

Automated verification with Playwright MCP

The Playwright MCP plugin is enabled (.claude/settings.local.json). Use it to verify UI changes without manually opening a browser.

After publishing to a local node:

1. browser_navigate → URL from local-republish.sh output
2. browser_snapshot → verify layout and content render correctly
3. browser_fill_form + browser_click → test message sending
4. browser_console_messages → check for WASM panics or errors
5. browser_resize → test mobile breakpoints (767px, 480px)

Against example data (no node needed):

cargo make build-ui-example-no-sync
cd target/dx/river-ui/release/web/public && python3 -m http.server 8082 &

Then browser_navigate → http://127.0.0.1:8082/

Typical iteration loop:

1. Edit UI code
2. ./scripts/local-republish.sh
3. browser_navigate to published URL
4. browser_snapshot to verify
5. browser_console_messages to check for errors

Debug overlay

Built-in debug overlay activated via ?debug=1 query parameter. Shows timestamped log messages on-screen with a minimize/expand toggle — essential for mobile where console is inaccessible.

http://{IP}:7510/v1/contract/web/{CONTRACT_ID}/?debug=1

Use crate::util::debug_log("msg") to log to the overlay. Does nothing without ?debug=1.

Panic overlay

A WASM panic hook creates a visible red error overlay showing the panic message. Appears automatically on any crash, no query param needed.

Signing flow

1. Room creation → create_room_modal.rs generates SigningKey, stores it in the ROOMS signal as RoomData::self_sk, and calls store_signing_key() to save a copy in the chat delegate
2. Message send → UI signs locally and synchronously: sign_message_locally(&msg_bytes, &self_sk). There is no delegate round-trip on the message path (freenet/river#512) — it could not change the signature bytes and it cost seconds of visible lag
3. Everything else (member, ban, config, member_info, secret, upgrade) → sign_*_with_fallback → send_delegate_request(Sign*{...}) → delegate looks up signing_key:{origin}:{room_key} → returns signature
4. Fallback → the delegate's answer is used only if it verifies under self_sk; otherwise (and on any delegate failure) the payload is signed locally with self_sk
5. Delta applied → Message added to local state → NEEDS_SYNC set → ProcessRooms → UPDATE sent

Key debugging points:

• A slow message send is not the SIGNING step — nothing is asked of the delegate there. Step 5 is a different matter: the NEEDS_SYNC effect also fires save_rooms_to_delegate() alongside the UPDATE, so a delegate op does contend for the same node afterwards
• For the other payload types, node logs show "Sign request for room, signature created: true/false" — if false, the delegate doesn't have the key
• Browser console shows the fallback path: "Delegate signing failed, using fallback"
• If no UPDATE appears in node logs after signing, check if the WebSocket is still connected

Check contract state via riverctl

riverctl --node-url ws://127.0.0.1:7510/v1/contract/command?encodingProtocol=native room list

Timeline analysis for message send

1. [send] signed OK (browser, with ?debug=1) → the message was signed locally
2. [send] delta applied OK → it is in local state and on screen
3. Update { key: ... } → UPDATE arrived at node
4. ResultRouter received result → UPDATE processed, result sent back to client

If step 2 happens but step 3 doesn't, the browser died between applying the message locally and sending the UPDATE. There is no delegate step here — see "Signing flow" above.

Firefox mobile: Dioxus RefCell re-entrant borrow panics

Firefox mobile runs Dioxus signal subscriber notifications synchronously during Drop, unlike Chrome/Safari which defer to microtask boundaries. This causes RefCell already borrowed panics in WASM at three levels:

1. Dioxus signal re-entrancy — ROOMS.with_mut() Drop triggers subscriber notifications that cascade into ROOMS.read(). Fix: use try_read() for all reactive signal reads. try_read() still registers Dioxus subscriptions (confirmed in Dioxus 0.7.x source) but returns Err instead of panicking.

2. wasm-bindgen-futures task re-entrancy — spawn_local inside a polled future causes re-entrant Task::run() at singlethread.rs:132. Fix: use safe_spawn_local() helper (in util.rs) that wraps spawn_local in setTimeout(0) to break out of the WASM call stack.

3. Signal mutation inside spawn_local — ROOMS.with_mut() inside a spawn_local task triggers notifications that re-queue the same task. Fix: move signal mutations out of spawn_local via setTimeout(0).

Key pattern for safe signal writes in WASM:

// WRONG — can cause re-entrant borrow in Firefox
spawn_local(async {
    // ... async work ...
    ROOMS.with_mut(|rooms| { /* mutate */ });
});

// RIGHT — defer mutation to clean execution context
#[cfg(target_arch = "wasm32")]
{
    let cb = Closure::once_into_js(move || {
        ROOMS.with_mut(|rooms| { /* mutate */ });
    });
    web_sys::window().unwrap()
        .set_timeout_with_callback(&cb.into()).ok();
}

Important: Signal clears in use_effect must be synchronous, not deferred. Deferring a clear that the effect subscribes to causes an infinite loop.

See mark_needs_sync() in app.rs and safe_spawn_local() in util.rs for canonical examples.

Common issues

Symptom	Cause	Fix
Messages fail to send (new room)	Signing key not stored in delegate	Fixed: create_room_modal.rs now calls store_signing_key after room creation
"signature created: false" in node logs	Delegate can't find signing key for room	Ensure StoreSigningKey is sent after room creation; fallback signs locally
Mobile send appears stuck	Browser suspends WASM when screen locks	Keep phone screen active; delegate signing avoids long async chains
RefCell already borrowed on Firefox mobile	Dioxus signal re-entrant borrow during Drop	Use try_read() instead of read() for reactive signal access
Crash at singlethread.rs:132	spawn_local inside polled future on Firefox	Use safe_spawn_local() to defer via setTimeout(0)
Blank page after code change (no panic)	Infinite loop from deferred signal clear	Keep signal clears synchronous in use_effect; only defer spawns