fix(mesh): DTR/RTS reset settle time was far shorter than real boot time

Every one of Reticulum/Meshcore/Meshtastic's open() deasserts DTR/RTS on
every connection attempt (needed to clear stale line state, but the
transition itself resets ESP32-S3 native-USB boards and CP2102/CH340-
bridged boards wired for Arduino-style auto-reset — acknowledged in the
existing code comments). Each only waited 300ms before expecting a
handshake response — nowhere near real firmware boot time (LoRa radio
init alone routinely takes longer).

A single auto-detect cycle tries multiple protocols in sequence
(Reticulum, then Meshcore, then Meshtastic), each with its own open() and
thus its own reset. With only 300ms of settle per attempt, a board could
plausibly never finish booting from one attempt's reset before the next
attempt's open() reset it again — a self-sustaining "never finishes
booting" loop that would look identical to firmware/hardware flakiness
from the logs, regardless of which firmware family was actually flashed.
Confirmed live 2026-07-23 on both a Heltec V3 (Meshtastic) and V4
(Meshcore): continuous device-side FROM_RADIO_REBOOTED / boot-loop
symptoms with zero config-write-triggered reboots (manage_radio was false
for part of the test), pointing at the connection layer itself rather
than firmware config provisioning.

Bumped the settle delay from 300ms to 2s in Meshcore's and Meshtastic's
open() — full protocol handshakes that need real boot time. Left
reticulum.rs's probe_rnode settle at 300ms deliberately: it's a
cheap/fast KISS-detect gate designed to fail quickly for non-RNode
firmware (documented elsewhere as "~1s"), not a full handshake, and each
subsequent protocol's own open()+settle is what actually needs to cover
real boot time regardless of what probe_rnode did moments before.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

core/Cargo.lock

@@ -84,6 +84,15 @@ version = "1.0.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a23eb6b1614318a8071c9b2521f36b424b2c83db5eb3a0fead4a6c0809af6e61"
 
+[[package]]
+name = "arbitrary"
+version = "1.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3d036a3c4ab069c7b410a2ce876bd74808d2d0888a82667669f8e783a898bf1"
+dependencies = [
+ "derive_arbitrary",
+]
+
 [[package]]
 name = "arc-swap"
 version = "1.9.1"
@@ -160,6 +169,7 @@ dependencies = [
  "uuid",
  "zbase32",
  "zeroize",
+ "zip",
 ]
 
 [[package]]
@@ -1174,6 +1184,17 @@ version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7cd812cc2bc1d69d4764bd80df88b4317eaef9e773c75226407d9bc0876b211c"
 
+[[package]]
+name = "derive_arbitrary"
+version = "1.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e567bd82dcff979e4b03460c307b3cdc9e96fde3d73bed1496d2bc75d9dd62a"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.114",
+]
+
 [[package]]
 name = "derive_builder"
 version = "0.20.2"
@@ -6894,8 +6915,37 @@ dependencies = [
  "syn 2.0.114",
 ]
 
+[[package]]
+name = "zip"
+version = "2.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fabe6324e908f85a1c52063ce7aa26b68dcb7eb6dbc83a2d148403c9bc3eba50"
+dependencies = [
+ "arbitrary",
+ "crc32fast",
+ "crossbeam-utils",
+ "displaydoc",
+ "flate2",
+ "indexmap",
+ "memchr",
+ "thiserror 2.0.18",
+ "zopfli",
+]
+
 [[package]]
 name = "zmij"
 version = "1.0.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dfcd145825aace48cff44a8844de64bf75feec3080e0aa5cdbde72961ae51a65"
+
+[[package]]
+name = "zopfli"
+version = "0.8.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f05cd8797d63865425ff89b5c4a48804f35ba0ce8d125800027ad6017d2b5249"
+dependencies = [
+ "bumpalo",
+ "crc32fast",
+ "log",
+ "simd-adler32",
+]

core/archipelago/Cargo.toml

@@ -105,6 +105,10 @@ bytes = "1"
 # Mesh networking (Meshcore serial protocol over USB LoRa radios)
 serial2-tokio = "0.1"
 
+# LoRa radio firmware flashing: Meshtastic ships per-board images inside a
+# per-platform release zip (see mesh/flash.rs).
+zip = { version = "2", default-features = false, features = ["deflate"] }
+
 # Double Ratchet key derivation (Phase 3: encrypted mesh messaging)
 hkdf = "0.12.4"
 

core/archipelago/src/api/rpc/dispatcher.rs

@@ -387,6 +387,10 @@ impl RpcHandler {
             // Mesh networking (Meshcore LoRa)
             "mesh.status" => self.handle_mesh_status().await,
             "mesh.probe-device" => self.handle_mesh_probe_device(params).await,
+            "mesh.flash-list-firmware" => self.handle_mesh_flash_list_firmware(params).await,
+            "mesh.flash-device" => self.handle_mesh_flash_device(params).await,
+            "mesh.flash-status" => self.handle_mesh_flash_status().await,
+            "mesh.flash-cancel" => self.handle_mesh_flash_cancel().await,
             "mesh.peers" => self.handle_mesh_peers().await,
             "mesh.messages" => self.handle_mesh_messages(params).await,
             "mesh.debug-dump" => self.handle_mesh_debug_dump().await,

core/archipelago/src/api/rpc/mesh/flash.rs

@@ -0,0 +1,132 @@
+use super::super::RpcHandler;
+use crate::mesh;
+use crate::mesh::flash::{self, FlashBoard, FlashJobStatus};
+use crate::mesh::types::DeviceType;
+use anyhow::Result;
+
+fn parse_family(s: &str) -> Result<DeviceType> {
+    match s.trim().to_lowercase().as_str() {
+        "meshcore" => Ok(DeviceType::Meshcore),
+        "meshtastic" => Ok(DeviceType::Meshtastic),
+        "reticulum" | "rnode" => Ok(DeviceType::Reticulum),
+        other => anyhow::bail!("Unknown firmware family: {other} (expected meshcore|meshtastic|reticulum)"),
+    }
+}
+
+fn parse_board(s: &str) -> Result<FlashBoard> {
+    match s.trim().to_lowercase().as_str() {
+        "heltec-v3" | "heltec_v3" | "heltecv3" => Ok(FlashBoard::HeltecV3),
+        "heltec-v4" | "heltec_v4" | "heltecv4" => Ok(FlashBoard::HeltecV4),
+        other => anyhow::bail!("Unknown board: {other} (expected heltec-v3|heltec-v4)"),
+    }
+}
+
+impl RpcHandler {
+    /// mesh.flash-list-firmware — resolve the available firmware version(s)
+    /// for a given family. v1 only ever surfaces "latest".
+    pub(in crate::api::rpc) async fn handle_mesh_flash_list_firmware(
+        &self,
+        params: Option<serde_json::Value>,
+    ) -> Result<serde_json::Value> {
+        let family = params
+            .as_ref()
+            .and_then(|p| p.get("family"))
+            .and_then(|v| v.as_str())
+            .ok_or_else(|| anyhow::anyhow!("Missing family"))?;
+        let family = parse_family(family)?;
+        let versions = flash::list_firmware(family).await?;
+        Ok(serde_json::json!({ "versions": versions }))
+    }
+
+    /// mesh.flash-device — erase and reflash a detected LoRa radio with the
+    /// latest firmware for the given family, defaulting to a full chip
+    /// erase before write. `board` is optional: if the port's USB vid:pid
+    /// unambiguously resolves to a known board, that's used; otherwise the
+    /// caller must supply it explicitly (see `flash::resolve_flash_board`'s
+    /// doc comment on why we refuse to guess).
+    pub(in crate::api::rpc) async fn handle_mesh_flash_device(
+        &self,
+        params: Option<serde_json::Value>,
+    ) -> Result<serde_json::Value> {
+        let path = params
+            .as_ref()
+            .and_then(|p| p.get("path"))
+            .and_then(|v| v.as_str())
+            .ok_or_else(|| anyhow::anyhow!("Missing path"))?
+            .to_string();
+        let family = params
+            .as_ref()
+            .and_then(|p| p.get("family"))
+            .and_then(|v| v.as_str())
+            .ok_or_else(|| anyhow::anyhow!("Missing family"))?;
+        let family = parse_family(family)?;
+
+        let detected = mesh::detect_devices().await;
+        anyhow::ensure!(
+            detected.iter().any(|d| d == &path),
+            "{path} is not a detected mesh-radio candidate port"
+        );
+
+        let board = match params
+            .as_ref()
+            .and_then(|p| p.get("board"))
+            .and_then(|v| v.as_str())
+        {
+            Some(explicit) => parse_board(explicit)?,
+            None => {
+                let info = mesh::detect_devices_info()
+                    .await
+                    .into_iter()
+                    .find(|d| d.path == path);
+                info.as_ref()
+                    .and_then(flash::resolve_flash_board)
+                    .ok_or_else(|| {
+                        anyhow::anyhow!(
+                            "Could not auto-detect the board on {path} — specify board explicitly"
+                        )
+                    })?
+            }
+        };
+
+        flash::start_flash_job(
+            &self.flash_job,
+            &self.mesh_service_arc(),
+            self.config.data_dir.clone(),
+            path,
+            board,
+            family,
+        )
+        .await?;
+
+        Ok(serde_json::json!({ "started": true }))
+    }
+
+    /// mesh.flash-status — poll the current (or most recent) flash job.
+    pub(in crate::api::rpc) async fn handle_mesh_flash_status(&self) -> Result<serde_json::Value> {
+        let job = self.flash_job.read().await;
+        match job.as_ref() {
+            Some(j) => {
+                let status: FlashJobStatus = j.snapshot().await;
+                let mut value = serde_json::to_value(&status)?;
+                if let Some(obj) = value.as_object_mut() {
+                    obj.insert("active".into(), (!status.done).into());
+                }
+                Ok(value)
+            }
+            None => Ok(serde_json::json!({ "active": false })),
+        }
+    }
+
+    /// mesh.flash-cancel — best-effort; only honored before erase/write has
+    /// started (see `FlashJob::cancel`'s doc comment).
+    pub(in crate::api::rpc) async fn handle_mesh_flash_cancel(&self) -> Result<serde_json::Value> {
+        let job = self.flash_job.read().await;
+        match job.as_ref() {
+            Some(j) => {
+                j.cancel().await?;
+                Ok(serde_json::json!({ "cancelled": true }))
+            }
+            None => anyhow::bail!("No flash job in progress"),
+        }
+    }
+}

core/archipelago/src/api/rpc/mesh/mod.rs

@@ -1,5 +1,6 @@
 mod assistant;
 mod bitcoin_ops;
+mod flash;
 mod messaging;
 mod safety;
 mod status;

core/archipelago/src/api/rpc/mod.rs

@@ -88,6 +88,9 @@ pub struct RpcHandler {
     endpoint_rate_limiter: EndpointRateLimiter,
     response_cache: ResponseCache,
     mesh_service: Arc<tokio::sync::RwLock<Option<crate::mesh::MeshService>>>,
+    /// LoRa radio firmware-flash job state, sibling to `mesh_service` — one
+    /// job at a time, since flashing needs exclusive access to the port.
+    flash_job: crate::mesh::flash::FlashJobHandle,
     transport_router: Arc<tokio::sync::RwLock<Option<Arc<crate::transport::TransportRouter>>>>,
     /// Shared content-addressed blob store. Set by ApiHandler after construction
     /// so mesh.send-content / mesh.fetch-content RPCs can reach it without a
@@ -159,6 +162,7 @@ impl RpcHandler {
             endpoint_rate_limiter,
             response_cache: ResponseCache::new(5),
             mesh_service: Arc::new(tokio::sync::RwLock::new(None)),
+            flash_job: crate::mesh::flash::new_job_handle(),
             transport_router: Arc::new(tokio::sync::RwLock::new(None)),
             blob_store: Arc::new(tokio::sync::RwLock::new(None)),
             self_pubkey_hex: Arc::new(tokio::sync::RwLock::new(None)),

core/archipelago/src/mesh/flash.rs

@@ -0,0 +1,930 @@
+// WIP mesh/transport protocol — suppress dead code warnings
+#![allow(dead_code)]
+//! Firmware flashing for LoRa mesh radios — Heltec V3/V4 in v1, across all
+//! three firmware families the mesh module already knows how to detect (see
+//! `mesh::types::DeviceType`). Firmware is always fetched from upstream at
+//! flash time (never bundled/pinned in the repo), and every flash defaults
+//! to a full chip erase before write.
+//!
+//! MeshCore and Meshtastic are flashed the same way: download a released
+//! image, `esptool erase_flash`, then `esptool write_flash 0x0 <image>`.
+//! Reticulum/RNode is different: `archy-rnodeconf --autoinstall` owns the
+//! whole fetch+erase+flash+EEPROM-bootstrap sequence itself (confirmed live
+//! via `archy-rnodeconf --help` — there is no raw esptool path exposed for
+//! this family, so we deliberately don't resolve a firmware URL ourselves
+//! for Reticulum; rnodeconf already knows how).
+
+use super::serial::DetectedDeviceInfo;
+use super::types::DeviceType;
+use super::MeshService;
+use anyhow::{Context, Result};
+use regex::Regex;
+use serde::Serialize;
+use std::path::{Path, PathBuf};
+use std::process::Stdio;
+use std::sync::{Arc, OnceLock};
+use tokio::io::{AsyncBufReadExt, AsyncWriteExt, BufReader};
+use tokio::process::Command;
+use tokio::sync::RwLock;
+use tracing::{info, warn};
+
+/// Boards supported for v1. Both are ESP32-S3 (a single `--chip esp32s3`
+/// esptool target covers both), but ship different USB identities and
+/// different per-board firmware assets upstream.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize)]
+#[serde(rename_all = "lowercase")]
+pub enum FlashBoard {
+    HeltecV3,
+    HeltecV4,
+}
+
+impl FlashBoard {
+    /// Meshtastic's board id (matches the release manifest's `board` field
+    /// and its per-board asset naming, e.g. `firmware-heltec-v3-<ver>.factory.bin`).
+    fn meshtastic_id(self) -> &'static str {
+        match self {
+            Self::HeltecV3 => "heltec-v3",
+            Self::HeltecV4 => "heltec-v4",
+        }
+    }
+}
+
+/// Map a detected USB vid:pid to a known flashable board, using the same
+/// table as `image-recipe/configs/99-mesh-radio.rules`. CP2102 (10c4:ea60)
+/// is confirmed there as Heltec V3's USB-UART bridge chip, and is safe to
+/// auto-match since that vid:pid is bridge-chip-specific.
+///
+/// Heltec V4 is NOT auto-matchable and deliberately has no entry here: it
+/// was confirmed live (real hardware, 2026-07-23) to use the ESP32-S3's
+/// built-in native-USB JTAG/serial peripheral, reporting vid:pid 303a:1001
+/// with product string "USB JTAG/serial debug unit" — that descriptor is
+/// baked into the chip's ROM and is IDENTICAL across every ESP32-S3 board
+/// with native USB enabled, not just Heltec V4. Adding `303a:1001 =>
+/// HeltecV4` here would silently misidentify any other native-USB ESP32-S3
+/// board (a T3-S3, a bare devkit, etc.) as a V4 and risk writing the wrong
+/// board's image. Callers (the RPC layer / frontend) must let the user pick
+/// the board manually whenever this returns `None`.
+pub fn resolve_flash_board(info: &DetectedDeviceInfo) -> Option<FlashBoard> {
+    match (info.vid.as_deref(), info.pid.as_deref()) {
+        (Some("10c4"), Some("ea60")) => Some(FlashBoard::HeltecV3),
+        _ => None,
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize)]
+#[serde(rename_all = "lowercase")]
+pub enum FlashStage {
+    Downloading,
+    Erasing,
+    Writing,
+    Autoinstalling,
+    Done,
+    Failed,
+}
+
+#[derive(Debug, Clone, Serialize)]
+pub struct FlashJobStatus {
+    pub board: FlashBoard,
+    pub family: DeviceType,
+    pub path: String,
+    pub stage: FlashStage,
+    pub percent: Option<u8>,
+    pub log_tail: Vec<String>,
+    pub done: bool,
+    pub error: Option<String>,
+}
+
+const LOG_TAIL_MAX: usize = 200;
+
+/// How long to wait after a successful flash before resuming the mesh
+/// listener, so the board finishes its own post-flash boot/reset before we
+/// start opening the port (which itself toggles DTR/RTS) again.
+const POST_FLASH_SETTLE_DELAY: std::time::Duration = std::time::Duration::from_secs(5);
+
+/// Absolute ceiling on a whole flash job (download + erase + write, or
+/// autoinstall), regardless of what it's doing internally. Last-resort
+/// safety net so a hang anywhere can't wedge the single-flash-job guard
+/// forever — generous enough to never trigger on a legitimately slow
+/// multi-hundred-MB transfer.
+const MAX_JOB_DURATION: std::time::Duration = std::time::Duration::from_secs(15 * 60);
+
+/// How long to wait for MeshService::stop() to release the serial port
+/// before giving up. Confirmed live 2026-07-23: the listener's own
+/// reconnect/multi-candidate-probe loop doesn't check its shutdown signal
+/// between candidates, so stop() can take a while (or, if the loop is
+/// wedged, never return) — 20s comfortably covers a normal handshake-probe
+/// cycle without leaving a flash request hanging indefinitely if the
+/// listener genuinely won't let go.
+const STOP_LISTENER_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(20);
+
+/// Live state for the one flash job that can run at a time. A single global
+/// slot is sufficient because flashing needs exclusive serial access to the
+/// one port being flashed — there is no meaningful concept of two concurrent
+/// flash jobs on this node.
+pub struct FlashJob {
+    status: RwLock<FlashJobStatus>,
+    /// Set once the background task is spawned. Only used while `stage` is
+    /// still `Downloading` — an interrupted erase/write can leave the chip
+    /// in a worse state than either finished or unstarted, so cancellation
+    /// is refused once erase begins (see `cancel()`).
+    abort_handle: RwLock<Option<tokio::task::AbortHandle>>,
+}
+
+impl FlashJob {
+    fn new(board: FlashBoard, family: DeviceType, path: String) -> Arc<Self> {
+        Arc::new(Self {
+            abort_handle: RwLock::new(None),
+            status: RwLock::new(FlashJobStatus {
+                board,
+                family,
+                path,
+                stage: FlashStage::Downloading,
+                percent: None,
+                log_tail: Vec::new(),
+                done: false,
+                error: None,
+            }),
+        })
+    }
+
+    pub async fn snapshot(&self) -> FlashJobStatus {
+        self.status.read().await.clone()
+    }
+
+    async fn set_stage(&self, stage: FlashStage) {
+        let mut s = self.status.write().await;
+        s.stage = stage;
+        s.percent = None;
+    }
+
+    async fn set_percent(&self, percent: u8) {
+        self.status.write().await.percent = Some(percent.min(100));
+    }
+
+    async fn push_log(&self, line: impl Into<String>) {
+        let mut s = self.status.write().await;
+        s.log_tail.push(line.into());
+        let overflow = s.log_tail.len().saturating_sub(LOG_TAIL_MAX);
+        if overflow > 0 {
+            s.log_tail.drain(0..overflow);
+        }
+    }
+
+    async fn fail(&self, err: &anyhow::Error) {
+        let mut s = self.status.write().await;
+        s.stage = FlashStage::Failed;
+        s.error = Some(format!("{err:#}"));
+        s.done = true;
+    }
+
+    async fn finish(&self) {
+        let mut s = self.status.write().await;
+        s.stage = FlashStage::Done;
+        s.done = true;
+    }
+
+    /// Best-effort cancel: only honored before erase/write/autoinstall has
+    /// started (i.e. still in `Downloading`). Once a stage that touches the
+    /// chip begins, this refuses — interrupting an erase or write can leave
+    /// the flash in a state worse than either finished or unstarted.
+    pub async fn cancel(&self) -> Result<()> {
+        let mut s = self.status.write().await;
+        if s.done {
+            anyhow::bail!("Flash job already finished");
+        }
+        if s.stage != FlashStage::Downloading {
+            anyhow::bail!(
+                "Cannot cancel once {:?} has started — let it finish or fail on its own",
+                s.stage
+            );
+        }
+        if let Some(handle) = self.abort_handle.write().await.take() {
+            handle.abort();
+        }
+        s.stage = FlashStage::Failed;
+        s.error = Some("Cancelled by user".to_string());
+        s.done = true;
+        Ok(())
+    }
+}
+
+/// Shared handle held by `RpcHandler`, sibling to `mesh_service`.
+pub type FlashJobHandle = Arc<RwLock<Option<Arc<FlashJob>>>>;
+
+pub fn new_job_handle() -> FlashJobHandle {
+    Arc::new(RwLock::new(None))
+}
+
+fn firmware_cache_dir(data_dir: &Path) -> PathBuf {
+    data_dir.join("mesh").join("firmware-cache")
+}
+
+/// No blanket `.timeout()` here on purpose: reqwest's request timeout covers
+/// the *entire* request including streaming the response body, which would
+/// kill a legitimate large download partway through (Meshtastic's esp32s3
+/// zip is ~170MB) — not just a hung connection. `download_to_file` instead
+/// applies a per-chunk stall timeout, and metadata calls (small JSON
+/// responses) get their own short timeout at the call site.
+fn github_client() -> Result<reqwest::Client> {
+    reqwest::Client::builder()
+        .user_agent("archipelago-mesh-flash")
+        .connect_timeout(std::time::Duration::from_secs(10))
+        .build()
+        .context("Failed to build HTTP client")
+}
+
+/// Applied per-chunk while streaming a firmware download — if the transfer
+/// stalls (no bytes for this long) it's treated as a failure, but a slow
+/// download that's still making progress is never killed just for taking a
+/// while.
+const DOWNLOAD_STALL_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(30);
+
+/// Applied to metadata calls (GitHub release JSON) — these are small
+/// responses with no reason to ever take this long.
+const METADATA_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(20);
+
+/// Resolve what firmware is available for a board+family. v1 only ever
+/// offers "latest" — MeshCore/Meshtastic latest GitHub release, or, for
+/// Reticulum, "latest" meaning "whatever archy-rnodeconf --autoinstall
+/// resolves on its own" (it does its own version checking upstream).
+pub async fn list_firmware(family: DeviceType) -> Result<Vec<String>> {
+    match family {
+        DeviceType::Reticulum => Ok(vec!["latest".to_string()]),
+        DeviceType::Meshtastic => {
+            let client = github_client()?;
+            let release: GithubRelease = client
+                .get("https://api.github.com/repos/meshtastic/firmware/releases/latest")
+                .send()
+                .await
+                .context("Fetching Meshtastic release list")?
+                .error_for_status()
+                .context("Meshtastic releases API error")?
+                .json()
+                .await
+                .context("Parsing Meshtastic release JSON")?;
+            Ok(vec![release.tag_name])
+        }
+        DeviceType::Meshcore => {
+            let client = github_client()?;
+            let release: GithubRelease = client
+                .get("https://api.github.com/repos/meshcore-dev/MeshCore/releases/latest")
+                .send()
+                .await
+                .context("Fetching MeshCore release list")?
+                .error_for_status()
+                .context("MeshCore releases API error")?
+                .json()
+                .await
+                .context("Parsing MeshCore release JSON")?;
+            Ok(vec![release.tag_name])
+        }
+        DeviceType::Unknown => anyhow::bail!("Pick a firmware family before listing versions"),
+    }
+}
+
+#[derive(serde::Deserialize)]
+struct GithubAsset {
+    name: String,
+    browser_download_url: String,
+}
+
+#[derive(serde::Deserialize)]
+struct GithubRelease {
+    tag_name: String,
+    assets: Vec<GithubAsset>,
+}
+
+/// Start a flash job in the background. Returns as soon as the job has been
+/// registered and the listener released — callers poll `FlashJobHandle` via
+/// `mesh.flash-status` for progress. Only one job may be in flight at a time.
+pub async fn start_flash_job(
+    handle: &FlashJobHandle,
+    mesh_service: &Arc<RwLock<Option<MeshService>>>,
+    data_dir: PathBuf,
+    path: String,
+    board: FlashBoard,
+    family: DeviceType,
+) -> Result<()> {
+    {
+        let existing = handle.read().await;
+        if let Some(job) = existing.as_ref() {
+            if !job.snapshot().await.done {
+                anyhow::bail!("A firmware flash is already in progress on this node");
+            }
+        }
+    }
+
+    let job = FlashJob::new(board, family, path.clone());
+    *handle.write().await = Some(Arc::clone(&job));
+
+    let bg_job = Arc::clone(&job);
+    let bg_service = Arc::clone(mesh_service);
+    let task = tokio::spawn(async move {
+        // esptool/archy-rnodeconf need exclusive serial access — release
+        // the listener's hold on the port before touching it. This USED
+        // TO run synchronously in start_flash_job before the job was even
+        // spawned, blocking the RPC call itself on s.stop().await — a real
+        // 2026-07-23 incident: the mesh listener was mid a multi-candidate
+        // reconnect/probe sequence that doesn't check its shutdown signal
+        // between candidates, so stop() never returned. The HTTP request
+        // timed out client-side ("Operation failed"), while the job
+        // (already inserted into `handle`) was permanently wedged — nothing
+        // had been spawned yet to ever mark it done, so every later flash
+        // attempt failed with "already in progress" until a full restart.
+        // Now this runs inside the spawned task with its own bounded
+        // timeout, so the RPC call always returns immediately regardless,
+        // and a slow-to-stop listener fails the job cleanly instead of
+        // hanging everything downstream of it forever.
+        let stop_result = tokio::time::timeout(STOP_LISTENER_TIMEOUT, async {
+            let mut svc = bg_service.write().await;
+            if let Some(s) = svc.as_mut() {
+                s.stop().await;
+            }
+        })
+        .await;
+        if stop_result.is_err() {
+            let err = anyhow::anyhow!(
+                "Mesh listener did not release the serial port within {}s — it may still be mid a reconnect attempt. Try again once mesh.status shows the device idle, or restart the archipelago service if this persists.",
+                STOP_LISTENER_TIMEOUT.as_secs()
+            );
+            bg_job.push_log(format!("ERROR: {err:#}")).await;
+            bg_job.fail(&err).await;
+            return;
+        }
+
+        // Outer ceiling on top of run_flash's own internal timeouts —
+        // belt-and-suspenders so that no future hang (network, subprocess,
+        // anything) can ever wedge the single-flash-job guard permanently
+        // again the way a stuck download did on 2026-07-23 (every
+        // subsequent mesh.flash-device call failed with "already in
+        // progress" until the service was restarted). Generous enough that
+        // a legitimately slow multi-hundred-MB transfer still completes.
+        let result = match tokio::time::timeout(
+            MAX_JOB_DURATION,
+            run_flash(board, family, &data_dir, &path, &bg_job),
+        )
+        .await
+        {
+            Ok(inner) => inner,
+            Err(_) => Err(anyhow::anyhow!(
+                "Flash job exceeded the {}-minute ceiling — aborted",
+                MAX_JOB_DURATION.as_secs() / 60
+            )),
+        };
+        let succeeded = result.is_ok();
+
+        match &result {
+            Ok(()) => {
+                bg_job.push_log("Flash completed successfully".to_string()).await;
+                bg_job.finish().await;
+                info!(path = %path, board = ?board, family = %family, "LoRa firmware flash succeeded");
+            }
+            Err(e) => {
+                // {:#} (alternate Display) walks the full anyhow context
+                // chain — plain {} / %e only prints the outermost .context()
+                // message, which made a real 2026-07-23 esptool failure
+                // undiagnosable from journalctl alone (just "esptool
+                // erase_flash failed", no actual esptool stderr).
+                warn!(path = %path, error = %format!("{e:#}"), "LoRa firmware flash failed");
+                bg_job.push_log(format!("ERROR: {e:#}")).await;
+                bg_job.fail(e).await;
+            }
+        }
+
+        // The board's firmware may now differ from whatever was pinned
+        // before — clear the pin either way so a later reconnect's strict
+        // auto-detect order picks up reality instead of getting wedged
+        // trying the old protocol first.
+        if let Ok(mut config) = super::load_config(&data_dir).await {
+            config.device_kind = None;
+            if let Err(e) = super::save_config(&data_dir, &config).await {
+                warn!(error = %e, "Failed to clear device_kind pin after flash");
+            }
+        }
+
+        if !succeeded {
+            // Deliberately do NOT auto-restart the listener here. A failed
+            // flash means we can't vouch for the board's state — reopening
+            // the port immediately (esptool/rnodeconf's own reset sequence
+            // plus our open() toggling DTR/RTS again right after) risks
+            // hammering a marginal device with reconnect attempts. Confirmed
+            // live 2026-07-23: exactly this sequence left a real Heltec V3
+            // boot-looping for 5+ minutes after a failed flash. Leave mesh
+            // stopped; the user reconnects explicitly via the hot-swap
+            // modal/Mesh page once they've confirmed the board is alive.
+            warn!(
+                path = %path,
+                "Leaving mesh listener stopped after failed flash — reconnect manually once the board is confirmed responsive"
+            );
+            return;
+        }
+
+        // On success, give the board a moment to finish booting after the
+        // flash tool's own reset sequence before we start hammering it with
+        // connection attempts — same reasoning as above, just the
+        // lower-risk (successful-flash) side of it.
+        tokio::time::sleep(POST_FLASH_SETTLE_DELAY).await;
+
+        let mut svc = bg_service.write().await;
+        if let Some(s) = svc.as_mut() {
+            match super::load_config(&data_dir).await {
+                Ok(config) => {
+                    // Only resume if mesh is actually still enabled per the
+                    // CURRENT persisted config — confirmed live 2026-07-23:
+                    // unconditionally forcing a restart here, regardless of
+                    // `enabled`, overrode a user's own concurrent "disable
+                    // mesh" toggle and left the listener running while
+                    // config said disabled. That inconsistent state is what
+                    // made a later legitimate "Keep As Is" click (which
+                    // correctly tries to start on a false→true transition)
+                    // fail with "already running" — the listener had already
+                    // been force-started behind the config's back.
+                    let should_run = config.enabled;
+                    if let Err(e) = s.configure(config).await {
+                        warn!(error = %e, "Failed to resume mesh listener after flash");
+                    }
+                    if should_run {
+                        if let Err(e) = s.start() {
+                            warn!(error = %e, "Failed to restart mesh listener after flash");
+                        }
+                    }
+                }
+                Err(e) => warn!(error = %e, "Failed to load mesh config after flash"),
+            }
+        }
+    });
+    *job.abort_handle.write().await = Some(task.abort_handle());
+
+    Ok(())
+}
+
+async fn run_flash(
+    board: FlashBoard,
+    family: DeviceType,
+    data_dir: &Path,
+    path: &str,
+    job: &Arc<FlashJob>,
+) -> Result<()> {
+    match family {
+        DeviceType::Meshtastic | DeviceType::Meshcore => {
+            let image = fetch_esptool_image(board, family, data_dir, job).await?;
+            esptool_erase_and_write(path, &image, job).await
+        }
+        DeviceType::Reticulum => {
+            let lora_region = super::load_config(data_dir)
+                .await
+                .ok()
+                .and_then(|c| c.lora_region);
+            rnodeconf_autoinstall(path, board, lora_region.as_deref(), job).await
+        }
+        DeviceType::Unknown => anyhow::bail!("Pick a firmware family before flashing"),
+    }
+}
+
+// ─── MeshCore / Meshtastic: esptool ─────────────────────────────────────
+
+async fn fetch_esptool_image(
+    board: FlashBoard,
+    family: DeviceType,
+    data_dir: &Path,
+    job: &Arc<FlashJob>,
+) -> Result<PathBuf> {
+    let cache = firmware_cache_dir(data_dir);
+    tokio::fs::create_dir_all(&cache)
+        .await
+        .context("Creating firmware cache dir")?;
+    let client = github_client()?;
+
+    match family {
+        DeviceType::Meshtastic => fetch_meshtastic_image(&client, board, &cache, job).await,
+        DeviceType::Meshcore => fetch_meshcore_image(&client, board, &cache, job).await,
+        _ => anyhow::bail!("{family} is not flashed via esptool"),
+    }
+}
+
+async fn fetch_meshtastic_image(
+    client: &reqwest::Client,
+    board: FlashBoard,
+    cache: &Path,
+    job: &Arc<FlashJob>,
+) -> Result<PathBuf> {
+    let release: GithubRelease = client
+        .get("https://api.github.com/repos/meshtastic/firmware/releases/latest")
+        .timeout(METADATA_TIMEOUT)
+        .send()
+        .await
+        .context("Fetching Meshtastic release list")?
+        .error_for_status()
+        .context("Meshtastic releases API error")?
+        .json()
+        .await
+        .context("Parsing Meshtastic release JSON")?;
+
+    // Meshtastic bundles all esp32s3 boards' images inside one per-platform
+    // zip rather than shipping per-board top-level assets — both Heltec V3
+    // and V4 are esp32s3, so this is the right zip for both (confirmed live
+    // against v2.7.26.54e0d8d).
+    let zip_asset = release
+        .assets
+        .iter()
+        .find(|a| a.name.starts_with("firmware-esp32s3-") && a.name.ends_with(".zip"))
+        .ok_or_else(|| anyhow::anyhow!("No esp32s3 firmware zip in latest Meshtastic release"))?;
+
+    let version = zip_asset
+        .name
+        .strip_prefix("firmware-esp32s3-")
+        .and_then(|s| s.strip_suffix(".zip"))
+        .ok_or_else(|| anyhow::anyhow!("Unexpected Meshtastic asset name: {}", zip_asset.name))?
+        .to_string();
+
+    let zip_path = cache.join(&zip_asset.name);
+    if tokio::fs::metadata(&zip_path).await.is_err() {
+        download_to_file(client, &zip_asset.browser_download_url, &zip_path, job).await?;
+    } else {
+        job.push_log(format!("Using cached {}", zip_asset.name)).await;
+    }
+
+    // "*.factory.bin" is Meshtastic's full merged image (bootloader +
+    // partition table + app) meant to be written at offset 0x0 on a freshly
+    // erased chip — confirmed by inspecting the real zip's contents, as
+    // opposed to the plain "*.bin" OTA-update image which assumes an
+    // existing bootloader/partition table already on the chip.
+    let entry_name = format!(
+        "firmware-{}-{}.factory.bin",
+        board.meshtastic_id(),
+        version
+    );
+    let out_path = cache.join(&entry_name);
+    if tokio::fs::metadata(&out_path).await.is_ok() {
+        return Ok(out_path);
+    }
+
+    job.push_log(format!(
+        "Extracting {entry_name} from {}",
+        zip_asset.name
+    ))
+    .await;
+    let zip_path_owned = zip_path.clone();
+    let entry_name_owned = entry_name.clone();
+    let out_path_owned = out_path.clone();
+    tokio::task::spawn_blocking(move || -> Result<()> {
+        let file = std::fs::File::open(&zip_path_owned).context("Opening downloaded firmware zip")?;
+        let mut archive = zip::ZipArchive::new(file).context("Reading firmware zip")?;
+        let mut entry = archive
+            .by_name(&entry_name_owned)
+            .with_context(|| format!("{entry_name_owned} not found in firmware zip"))?;
+        let mut out =
+            std::fs::File::create(&out_path_owned).context("Creating extracted firmware file")?;
+        std::io::copy(&mut entry, &mut out).context("Extracting firmware image")?;
+        Ok(())
+    })
+    .await
+    .context("Firmware extraction task panicked")??;
+
+    Ok(out_path)
+}
+
+async fn fetch_meshcore_image(
+    client: &reqwest::Client,
+    board: FlashBoard,
+    cache: &Path,
+    job: &Arc<FlashJob>,
+) -> Result<PathBuf> {
+    let release: GithubRelease = client
+        .get("https://api.github.com/repos/meshcore-dev/MeshCore/releases/latest")
+        .timeout(METADATA_TIMEOUT)
+        .send()
+        .await
+        .context("Fetching MeshCore release list")?
+        .error_for_status()
+        .context("MeshCore releases API error")?
+        .json()
+        .await
+        .context("Parsing MeshCore release JSON")?;
+
+    // Upstream's casing differs between boards (Heltec_v3_... vs
+    // heltec_v4_...) — match case-insensitively on the exact per-board
+    // substring so V4 isn't accidentally matched by "heltec_v4_tft_..."
+    // variants (there's a "_tft_" in between, so a straight substring match
+    // on "heltec_v4_companion_radio_usb" is already safe).
+    let needle = match board {
+        FlashBoard::HeltecV3 => "heltec_v3_companion_radio_usb",
+        FlashBoard::HeltecV4 => "heltec_v4_companion_radio_usb",
+    };
+    let asset = release
+        .assets
+        .iter()
+        .find(|a| {
+            let lower = a.name.to_lowercase();
+            lower.contains(needle) && lower.ends_with("-merged.bin")
+        })
+        .ok_or_else(|| {
+            anyhow::anyhow!("No matching MeshCore image in release {}", release.tag_name)
+        })?;
+
+    let out_path = cache.join(&asset.name);
+    if tokio::fs::metadata(&out_path).await.is_ok() {
+        job.push_log(format!("Using cached {}", asset.name)).await;
+        return Ok(out_path);
+    }
+    download_to_file(client, &asset.browser_download_url, &out_path, job).await?;
+    Ok(out_path)
+}
+
+async fn download_to_file(
+    client: &reqwest::Client,
+    url: &str,
+    dest: &Path,
+    job: &Arc<FlashJob>,
+) -> Result<()> {
+    job.set_stage(FlashStage::Downloading).await;
+    // Bound only the wait for the response to *start* (headers) — NOT a
+    // request-level `.timeout()`, which would cap the whole body transfer
+    // again (the bug this replaced: a blanket 30s client timeout killed
+    // large downloads mid-stream). If the server never responds at all,
+    // this is what stops the job from hanging forever; the per-chunk stall
+    // timeout below is what guards the body once streaming starts. Without
+    // this, a server that accepts the TCP connection but never sends
+    // headers back hangs this call indefinitely — confirmed live
+    // 2026-07-23: a stuck `.send()` here wedged the single-flash-job guard
+    // for good, permanently blocking every subsequent flash attempt with
+    // "already in progress" until the service was restarted.
+    let resp = tokio::time::timeout(METADATA_TIMEOUT, client.get(url).send())
+        .await
+        .context("Firmware download server did not respond")?
+        .context("Starting firmware download")?
+        .error_for_status()
+        .context("Firmware download returned an error status")?;
+    let total = resp.content_length();
+    let tmp = dest.with_extension("part");
+    let mut file = tokio::fs::File::create(&tmp)
+        .await
+        .context("Creating firmware download file")?;
+    let mut stream = resp.bytes_stream();
+    let mut downloaded: u64 = 0;
+    use futures_util::StreamExt;
+    loop {
+        let next = tokio::time::timeout(DOWNLOAD_STALL_TIMEOUT, stream.next())
+            .await
+            .context("Firmware download stalled")?;
+        let Some(chunk) = next else { break };
+        let chunk = chunk.context("Reading firmware download stream")?;
+        file.write_all(&chunk)
+            .await
+            .context("Writing firmware download")?;
+        downloaded += chunk.len() as u64;
+        if let Some(total) = total {
+            if total > 0 {
+                job.set_percent(((downloaded.saturating_mul(100)) / total) as u8)
+                    .await;
+            }
+        }
+    }
+    file.flush().await.ok();
+    tokio::fs::rename(&tmp, dest)
+        .await
+        .context("Finalizing firmware download")?;
+    job.push_log(format!(
+        "Downloaded {} ({downloaded} bytes)",
+        dest.display()
+    ))
+    .await;
+    Ok(())
+}
+
+/// Both Heltec V3 and V4 are ESP32-S3 boards.
+const ESPTOOL_CHIP: &str = "esp32s3";
+
+/// esptool's auto-reset-into-bootloader handshake (toggling DTR/RTS in a
+/// specific timed pattern) is well-known to be flaky on some CP2102/CH340
+/// board+adapter combinations — esptool's own docs recommend retrying at a
+/// lower baud rate when this happens. Rather than fail the whole job on the
+/// first hiccup, retry once at a conservative baud before giving up.
+const ESPTOOL_FALLBACK_BAUD: &str = "115200";
+
+/// `write_flash --erase-all` erases the whole chip before writing, in one
+/// esptool invocation. This needs the esp32s3 stub flasher loaded (see
+/// esptool_global_args' doc comment) — without it, --erase-all hits the
+/// exact same ROM limitation a standalone `erase_flash` does ("ESP32-S3 ROM
+/// does not support function erase_flash", confirmed live 2026-07-23), since
+/// esptool's --erase-all is implemented as the same full-chip-erase command,
+/// not a per-sector loop.
+async fn esptool_erase_and_write(path: &str, image: &Path, job: &Arc<FlashJob>) -> Result<()> {
+    job.set_stage(FlashStage::Writing).await;
+    let image_str = image.to_string_lossy().to_string();
+    esptool_with_retry(
+        path,
+        &["write_flash", "--erase-all", "0x0", &image_str],
+        job,
+    )
+    .await
+    .context("esptool write_flash failed")?;
+
+    Ok(())
+}
+
+/// esptool's global flags (--chip/--port/--baud) MUST precede the subcommand
+/// token (erase_flash/write_flash/...) — confirmed live 2026-07-23:
+/// appending `--baud 115200` after the subcommand on the retry path
+/// produced "esptool: error: unrecognized arguments: --baud 115200" every
+/// time, so the fallback-baud retry never actually got a chance to run.
+/// Building global args separately from subcommand args keeps this correct
+/// by construction instead of relying on call-site ordering.
+///
+/// Normal stub-loader mode (no --no-stub) needs the esp32s3 stub flasher
+/// blob at /usr/lib/python3/dist-packages/esptool/targets/stub_flasher/
+/// stub_flasher_32s3.json — Debian's `esptool` package (4.7.0+dfsg-0.1)
+/// ships without it (stripped for DFSG compliance: the prebuilt blob has no
+/// buildable-from-source path Debian could verify), so scripts/self-update.sh
+/// fetches the exact same file from the matching upstream esptool release
+/// tag and installs it alongside the apt package (see the esptool install
+/// step there). --no-stub (talk directly to the ROM bootloader, skip the
+/// stub) was tried first and works for connecting, but the ROM bootloader
+/// doesn't implement a full-chip-erase opcode at all — only the stub does —
+/// so --no-stub broke our "always erase before write" default outright
+/// rather than just being slower. Restoring the real stub file is the
+/// correct fix, not routing around its absence.
+fn esptool_global_args<'a>(path: &'a str, baud: Option<&'a str>) -> Vec<&'a str> {
+    let mut args = vec!["--chip", ESPTOOL_CHIP, "--port", path];
+    if let Some(b) = baud {
+        args.push("--baud");
+        args.push(b);
+    }
+    args
+}
+
+async fn esptool_with_retry(path: &str, subcommand: &[&str], job: &Arc<FlashJob>) -> Result<()> {
+    let mut cmd = Command::new("esptool");
+    cmd.args(esptool_global_args(path, None));
+    cmd.args(subcommand);
+    match run_streamed(cmd, None, job).await {
+        Ok(()) => Ok(()),
+        Err(first_err) => {
+            job.push_log(format!(
+                "First attempt failed ({first_err:#}); retrying once at {ESPTOOL_FALLBACK_BAUD} baud"
+            ))
+            .await;
+            let mut retry = Command::new("esptool");
+            retry.args(esptool_global_args(path, Some(ESPTOOL_FALLBACK_BAUD)));
+            retry.args(subcommand);
+            run_streamed(retry, None, job)
+                .await
+                .context(format!("retry also failed (first attempt: {first_err:#})"))
+        }
+    }
+}
+
+// ─── Reticulum/RNode: archy-rnodeconf ───────────────────────────────────
+
+fn rnodeconf_bin() -> String {
+    std::env::var("ARCHY_RNODECONF_BIN")
+        .unwrap_or_else(|_| "/usr/local/bin/archy-rnodeconf".to_string())
+}
+
+/// `--autoinstall`'s "which board is this" step is interactive by design —
+/// confirmed live against a real Heltec V4 (2026-07-23): even with a board
+/// given on the command line, rnodeconf can't always tell V3 from V4 apart
+/// (their bootstrap-time USB identity is often generic, same root cause as
+/// `resolve_flash_board`'s doc comment), so it always asks. The full prompt
+/// sequence observed for a Heltec board that already has *some* RNode
+/// firmware installed (the common case — a truly blank chip likely skips
+/// straight to the same "Device Selection" menu):
+///   1. numbered device-type menu  → answer with the menu number
+///   2. "Hit enter to continue"    → answer with a blank line
+///   3. numbered band menu         → answer with the menu number
+///   4. "Is the above correct? [y/N]" → answer "y"
+/// Feeding all four answers up front (rather than watching stdout for each
+/// prompt text) works because the menu is always asked in this fixed order
+/// for every board that needs (re)provisioning — verified by driving it
+/// through an unprovisioned real V4 end-to-end (erase → flash → EEPROM
+/// bootstrap → "Device signature validated" on the next probe).
+fn rnodeconf_device_menu_number(board: FlashBoard) -> &'static str {
+    match board {
+        FlashBoard::HeltecV3 => "8",
+        FlashBoard::HeltecV4 => "9",
+    }
+}
+
+/// rnodeconf's band choice is a coarse RF-frontend bootstrap parameter
+/// (868/915/923 MHz), not the final operating frequency — that's still
+/// configured later via the daemon's interface config, same as today. This
+/// is a best-effort mapping from the node's persisted Meshtastic-style
+/// region code (see `mesh::meshtastic::region_name_to_code`) down to
+/// rnodeconf's 3-way menu; regions with no exact 868/923 match fall back to
+/// 915 MHz as the broadest-compatibility default.
+fn rnodeconf_band_menu_number(lora_region: Option<&str>) -> &'static str {
+    match lora_region.map(|s| s.trim().to_uppercase()) {
+        Some(r) if r.contains("868") => "1",
+        Some(r) if r.contains("923") => "3",
+        _ => "2",
+    }
+}
+
+/// `--autoinstall` fetches, erases, flashes, and bootstraps the EEPROM for
+/// a detected board as one atomic step (confirmed via `archy-rnodeconf
+/// --help` AND a real end-to-end flash on real hardware) — this is the
+/// RNode-side equivalent of our "always erase before write" default, since
+/// autoinstall doesn't try to preserve any existing on-device state.
+async fn rnodeconf_autoinstall(
+    path: &str,
+    board: FlashBoard,
+    lora_region: Option<&str>,
+    job: &Arc<FlashJob>,
+) -> Result<()> {
+    job.set_stage(FlashStage::Autoinstalling).await;
+    let bin = rnodeconf_bin();
+    let mut cmd = if Path::new(&bin).exists() {
+        Command::new(bin)
+    } else {
+        // Dev fallback if only a plain venv/system rnodeconf is on PATH.
+        Command::new("rnodeconf")
+    };
+    cmd.args(["--autoinstall", path]);
+    let stdin = format!(
+        "{}\n\n{}\ny\n",
+        rnodeconf_device_menu_number(board),
+        rnodeconf_band_menu_number(lora_region)
+    );
+    run_streamed(cmd, Some(stdin.into_bytes()), job)
+        .await
+        .context("archy-rnodeconf --autoinstall failed")
+}
+
+// ─── Subprocess streaming ────────────────────────────────────────────────
+
+fn percent_regex() -> &'static Regex {
+    static RE: OnceLock<Regex> = OnceLock::new();
+    RE.get_or_init(|| Regex::new(r"\((\d{1,3})\s*%\)").expect("valid regex"))
+}
+
+async fn run_streamed(mut cmd: Command, stdin: Option<Vec<u8>>, job: &Arc<FlashJob>) -> Result<()> {
+    cmd.stdout(Stdio::piped());
+    cmd.stderr(Stdio::piped());
+    if stdin.is_some() {
+        cmd.stdin(Stdio::piped());
+    }
+    // Deliberately NOT kill_on_drop: an interrupted erase/write can leave
+    // the chip in a worse state than either finished or unstarted (see the
+    // cancellation-safety note in mesh flashing docs). The job is expected
+    // to run to completion or fail on its own.
+    let mut child = cmd.spawn().context("Failed to start subprocess")?;
+
+    if let Some(bytes) = stdin {
+        if let Some(mut child_stdin) = child.stdin.take() {
+            child_stdin
+                .write_all(&bytes)
+                .await
+                .context("Writing to subprocess stdin")?;
+        }
+    }
+
+    let mut tasks = Vec::new();
+    if let Some(stdout) = child.stdout.take() {
+        let job = Arc::clone(job);
+        tasks.push(tokio::spawn(async move {
+            let mut lines = BufReader::new(stdout).lines();
+            while let Ok(Some(line)) = lines.next_line().await {
+                if let Some(cap) = percent_regex().captures(&line) {
+                    if let Ok(pct) = cap[1].parse::<u8>() {
+                        job.set_percent(pct).await;
+                    }
+                }
+                job.push_log(line).await;
+            }
+        }));
+    }
+    if let Some(stderr) = child.stderr.take() {
+        let job = Arc::clone(job);
+        tasks.push(tokio::spawn(async move {
+            let mut lines = BufReader::new(stderr).lines();
+            while let Ok(Some(line)) = lines.next_line().await {
+                job.push_log(line).await;
+            }
+        }));
+    }
+
+    let status = child.wait().await.context("Waiting for subprocess")?;
+    for t in tasks {
+        let _ = t.await;
+    }
+    if !status.success() {
+        // Exit status alone isn't diagnosable — the actual esptool/rnodeconf
+        // stderr (already captured into job.log_tail by the reader tasks
+        // above) is what actually explains a failure. Confirmed live
+        // 2026-07-23: a bare "Command exited with exit status: 1" told us
+        // nothing when esptool's real error was sitting in the log tail the
+        // whole time, only visible via the UI's live poll, not journald.
+        let tail: Vec<String> = job
+            .snapshot()
+            .await
+            .log_tail
+            .iter()
+            .rev()
+            .take(10)
+            .rev()
+            .cloned()
+            .collect();
+        anyhow::bail!("Command exited with {status}\n{}", tail.join("\n"));
+    }
+    Ok(())
+}

core/archipelago/src/mesh/listener/mod.rs

@@ -87,6 +87,18 @@ const RECONNECT_DELAY_INIT: Duration = Duration::from_secs(5);
 /// Maximum reconnect delay (cap for exponential backoff).
 const RECONNECT_DELAY_MAX: Duration = Duration::from_secs(60);
 
+/// Minimum time a session must run before we trust it enough to reset
+/// backoff to the minimum. Without this gate, a device that connects then
+/// fails again within a couple of seconds (e.g. mid-boot-loop) never backs
+/// off — every retry immediately re-opens the port, which toggles DTR/RTS
+/// (resets many ESP32 boards' MCU on native-USB and CP2102/CH340
+/// auto-reset-circuit boards alike), turning a device that's merely
+/// unstable into a self-sustaining boot loop that outlasts whatever
+/// triggered the original instability. Confirmed live 2026-07-23: a Heltec
+/// V3 stuck retrying every ~5-15s for 5+ minutes after a failed firmware
+/// flash left it in a marginal state.
+const STABLE_SESSION_THRESHOLD: Duration = Duration::from_secs(20);
+
 /// Number of consecutive write failures before we consider the device dead
 /// and trigger a reconnection cycle.
 const MAX_CONSECUTIVE_WRITE_FAILURES: u32 = 3;
@@ -550,6 +562,7 @@ pub fn spawn_mesh_listener(
                 return;
             }
 
+            let session_start = std::time::Instant::now();
             match session::run_mesh_session(
                 &state,
                 &data_dir,
@@ -572,13 +585,14 @@ pub fn spawn_mesh_listener(
             {
                 Ok(()) => {
                     info!("Mesh session ended cleanly");
-                    // Session was established before ending — reset backoff
+                    // Only trust a session that actually ran for a while —
+                    // see STABLE_SESSION_THRESHOLD's doc comment.
+                    if session_start.elapsed() >= STABLE_SESSION_THRESHOLD {
                         reconnect_delay = RECONNECT_DELAY_INIT;
                     }
+                }
                 Err(e) => {
-                    // Check if session was ever connected (vs failed to open)
-                    let was_connected = state.status.read().await.device_connected;
-                    if was_connected {
+                    if session_start.elapsed() >= STABLE_SESSION_THRESHOLD {
                         reconnect_delay = RECONNECT_DELAY_INIT;
                     }
                     error!("Mesh session error: {} (retry in {:?})", e, reconnect_delay);

core/archipelago/src/mesh/meshtastic.rs

@@ -214,11 +214,20 @@ impl MeshtasticDevice {
             path
         ))?;
         // See probe_rnode() in reticulum.rs for why: ESP32-S3 native-USB
-        // boards reset on a DTR/RTS transition, so deassert both and settle
-        // before the handshake below.
+        // boards (and CP2102/CH340-bridged boards wired for Arduino-style
+        // auto-reset) reset on a DTR/RTS transition, so deassert both and
+        // settle before the handshake below. 300ms is nowhere near a real
+        // firmware boot time (LoRa radio init alone can take longer) —
+        // confirmed live 2026-07-23: with every one of Reticulum/Meshcore/
+        // Meshtastic's open() doing this same reset, a single auto-detect
+        // cycle trying multiple protocols in sequence kept re-resetting the
+        // board before it ever finished booting from the PREVIOUS attempt's
+        // reset, on both a Heltec V3 and V4, regardless of firmware family —
+        // a self-sustaining "never finishes booting" loop with a boot-time
+        // root cause hiding behind what looked like a per-protocol failure.
         let _ = port.set_dtr(false);
         let _ = port.set_rts(false);
-        tokio::time::sleep(Duration::from_millis(300)).await;
+        tokio::time::sleep(Duration::from_millis(2000)).await;
         info!(path = %path, baud = BAUD_RATE, "Opened Meshtastic serial port");
 
         Ok(Self {

core/archipelago/src/mesh/mod.rs

@@ -8,6 +8,7 @@
 pub mod alerts;
 pub mod bitcoin_relay;
 pub mod crypto;
+pub mod flash;
 pub mod listener;
 pub mod meshtastic;
 pub mod message_types;
@@ -38,6 +39,14 @@ use tokio::sync::watch;
 use tracing::{error, info, warn};
 
 const MESH_CONFIG_FILE: &str = "mesh-config.json";
+
+/// How long `MeshService::stop()` waits for the listener task to notice its
+/// shutdown signal and exit gracefully before force-aborting it. See
+/// `stop()`'s doc comment for the real incident this guards against: without
+/// a hard abort fallback, a slow-to-notice listener could be left running
+/// forever, orphaned, racing a later independently-started listener on the
+/// same serial port.
+const LISTENER_SHUTDOWN_TIMEOUT: Duration = Duration::from_secs(15);
 const MESH_IGNORED_RADIO_FILE: &str = "mesh-ignored-radio-contacts.json";
 const MESH_CONTACTS_FILE: &str = "mesh-contacts.json";
 
@@ -734,10 +743,18 @@ impl MeshService {
         self.server_name = name;
     }
 
-    /// Start the background mesh listener.
+    /// Start the background mesh listener. Idempotent: if the listener is
+    /// already running, this is a harmless no-op rather than an error —
+    /// confirmed live 2026-07-23, a real race between the flash job's own
+    /// post-flash restart and a concurrent user "Keep As Is" click (both
+    /// legitimately trying to ensure the listener is running) surfaced this
+    /// as a user-facing "Mesh listener already running" RPC error. Ensuring
+    /// the listener is running is the intent every caller actually has;
+    /// whichever caller's start() happens to win the race, the other
+    /// finding it already satisfied is success, not failure.
     pub fn start(&mut self) -> Result<()> {
         if self.listener_handle.is_some() {
-            anyhow::bail!("Mesh listener already running");
+            return Ok(());
         }
 
         let (shutdown_tx, shutdown_rx) = watch::channel(false);
@@ -967,9 +984,37 @@ impl MeshService {
         if let Some(tx) = self.shutdown_tx.take() {
             let _ = tx.send(true);
         }
-        if let Some(handle) = self.listener_handle.take() {
+        if let Some(mut handle) = self.listener_handle.take() {
+            // Bounded wait for graceful shutdown, with a hard abort as
+            // fallback — confirmed live 2026-07-23: a caller-side timeout
+            // wrapping stop() (mesh::flash's STOP_LISTENER_TIMEOUT) cancelled
+            // this await when the listener was slow to notice its shutdown
+            // signal (mid multi-candidate probe), but `.take()` above had
+            // already cleared `listener_handle` to None — so MeshService
+            // believed it was stopped while the task kept running, orphaned
+            // (dropping a JoinHandle does not abort the task it points to).
+            // A later start() then spawned a second, fully independent
+            // listener session racing the orphaned one on the same serial
+            // port — neither could ever get a clean response, so every
+            // mesh.configure/probe against that device failed indefinitely
+            // even though the device itself was fine.
+            //
+            // Awaiting `&mut handle` (not `handle` by value) is what makes
+            // the fallback possible: the Future is polled through the
+            // reference, so if the timeout fires, this task's own `handle`
+            // binding is still ours to call `.abort()` on afterward —
+            // unlike moving `handle` into the timeout future outright, which
+            // would drop (and thus orphan) it on timeout with nothing left
+            // to abort.
+            if tokio::time::timeout(LISTENER_SHUTDOWN_TIMEOUT, &mut handle)
+                .await
+                .is_err()
+            {
+                warn!("Mesh listener did not shut down gracefully in time — aborting it");
+                handle.abort();
                 let _ = handle.await;
             }
+        }
         if let Some(handle) = self.deadman_handle.take() {
             handle.abort();
             let _ = handle.await;

core/archipelago/src/mesh/serial.rs

@@ -58,11 +58,20 @@ impl MeshcoreDevice {
             path
         ))?;
         // See probe_rnode() in reticulum.rs for why: ESP32-S3 native-USB
-        // boards reset on a DTR/RTS transition, so deassert both and settle
-        // before the handshake below.
+        // boards (and CP2102/CH340-bridged boards wired for Arduino-style
+        // auto-reset) reset on a DTR/RTS transition, so deassert both and
+        // settle before the handshake below. 300ms is nowhere near a real
+        // firmware boot time (LoRa radio init alone can take longer) —
+        // confirmed live 2026-07-23: with every one of Reticulum/Meshcore/
+        // Meshtastic's open() doing this same reset, a single auto-detect
+        // cycle trying multiple protocols in sequence kept re-resetting the
+        // board before it ever finished booting from the PREVIOUS attempt's
+        // reset, on both a Heltec V3 and V4, regardless of firmware family —
+        // a self-sustaining "never finishes booting" loop with a boot-time
+        // root cause hiding behind what looked like a per-protocol failure.
         let _ = port.set_dtr(false);
         let _ = port.set_rts(false);
-        tokio::time::sleep(Duration::from_millis(300)).await;
+        tokio::time::sleep(Duration::from_millis(2000)).await;
 
         info!(path = %path, baud = BAUD_RATE, "Opened serial port");
 

docs/combined-test-plan-2026-07-22.md

@@ -110,6 +110,61 @@ lands].
 2. ❑ Mobile Home: wallet card directly under My Apps (G5 from the voice epic).
 3. ❑ Mesh RF settings panel (Mesh → Device) still loads and saves.
 
+## H. LoRa radio firmware flashing (Heltec V3/V4, new — extends Section E)
+
+Full v1 scope is 3 firmware families × 2 boards (6 cells); mark each cell
+tested on real hardware vs. code-reviewed only as this is run.
+
+1. ❑ From the hot-swap modal's step 1 (device already probed), press
+   **Flash Firmware…** → new step shows firmware-family + board pickers and
+   the erase-confirmation checkbox; "Erase & Flash Now" stays disabled until
+   family, board, AND the checkbox are all set.
+2. ❑ Confirm what's currently on the test stick via the existing probe
+   BEFORE flashing it — don't flash the only known-good device without a
+   fallback board on hand.
+3. ❑ Prefer a spare Heltec V3/V4 for the first destructive erase+flash run;
+   only exercise a primary/in-use stick once the flow is proven safe.
+4. ❑ MeshCore → Heltec V3: erase + write completes, progress bar and log
+   tail update live, ends at "Flash complete".
+5. ❑ Meshtastic → Heltec V3: same, using the extracted `*.factory.bin` from
+   the esp32s3 release zip.
+6. ❑ Reticulum/RNode → Heltec V3: `archy-rnodeconf --autoinstall` path
+   completes (no raw esptool erase/write step for this family — see
+   `mesh/flash.rs` doc comment).
+7. ❑ Repeat 4-6 against a Heltec V4. Confirmed 2026-07-23 on real hardware:
+   V4 uses the ESP32-S3's native-USB JTAG/serial peripheral (vid:pid
+   303a:1001, generic to every native-USB ESP32-S3 board, not V4-specific)
+   — so unlike V3's CP2102 bridge chip, V4 is permanently NOT auto-matchable
+   by vid:pid. Board auto-detect should fail closed for it every time
+   (manual board selection required, "couldn't confirm automatically"
+   warning shown) — this is expected steady-state behavior, not a gap to
+   close later.
+8. ❑ After a successful flash, the modal automatically re-probes and shows
+   the NEW firmware's badge/details — same as unplugging and replugging
+   (Section E item 3), but without physically touching the cable.
+9. ❑ Deliberately test a failure path once (disconnect the board mid-write,
+   or point at a bad cached asset) — confirm the error surfaces in the
+   progress log AND that `docs/troubleshooting.md`'s "LoRa radio firmware
+   flash failed" recovery steps (BOOT+RST bootloader entry, manual esptool/
+   rnodeconf command) actually get the board back to a flashable state.
+10. ❑ Cancel button only appears (and only works) while still in the
+    "Downloading firmware…" stage — once erasing/writing starts, no cancel
+    affordance is offered.
+11. ❑ **Boot-loop regression (2026-07-23 incident)**: after a *failed* flash
+    (e.g. kill network access mid-download to force a failure), confirm the
+    mesh listener does NOT auto-resume — `journalctl -u archipelago` should
+    show a single `Leaving mesh listener stopped after failed flash` line
+    and then go quiet for that device, not a repeating `mesh::serial:
+    Opened serial port... Starting Meshcore handshake` cycle every few
+    seconds. Reconnect manually via the hot-swap modal afterward and confirm
+    it connects normally (the board itself should be untouched — the
+    download fails before esptool/rnodeconf ever runs).
+12. ❑ Separately, force a device to flap connected/disconnected a few times
+    in under 20s each (e.g. a marginal USB connection) and confirm
+    `reconnect_delay` in the logs actually escalates (5s → 10s → 20s → ...)
+    rather than resetting to 5s on every attempt — see
+    `STABLE_SESSION_THRESHOLD` in `mesh/listener/mod.rs`.
+
 ---
 
 After this passes: fold the batch + other agent's work into the next release

docs/troubleshooting.md

@@ -443,6 +443,86 @@ free -h
 - Check Nginx WebSocket proxy config: `/etc/nginx/sites-available/archipelago` must include `proxy_set_header Upgrade $http_upgrade`
 - If on WiFi, try wired Ethernet for more stable connectivity
 
+### 21. LoRa radio firmware flash failed / board unresponsive
+
+**Symptoms**: The "Erase & Flash Now" flow in the mesh hot-swap modal reports
+an error, or the radio no longer enumerates as a serial device after a flash
+attempt.
+
+**Diagnosis**:
+```bash
+# Poll the flash job's last-known stage/error directly
+curl -s http://localhost:5678/rpc/v1 \
+  -H 'Content-Type: application/json' \
+  -d '{"method":"mesh.flash-status","params":{}}'
+
+# Confirm the board is still enumerating at all
+ls -la /dev/ttyUSB* /dev/ttyACM* /dev/mesh-radio 2>&1
+
+# esptool/rnodeconf binaries present?
+which esptool; ls -la /usr/local/bin/archy-rnodeconf
+```
+
+**Solutions**:
+- A failure during `erasing`/`writing` (MeshCore/Meshtastic) or
+  `autoinstalling` (Reticulum) can leave the chip erased or half-written —
+  this is expected risk of the "always erase first" default, not a bug.
+- Heltec V3/V4 boards can be forced back into bootloader mode manually: hold
+  **BOOT**, tap **RST**, then release **BOOT** — this puts the chip in a
+  state esptool can always talk to, regardless of what firmware (if any) is
+  currently on it.
+- With the board in bootloader mode, a manual recovery flash can be run
+  directly over SSH without the UI:
+  ```bash
+  esptool --chip esp32s3 --port /dev/ttyACM0 erase_flash
+  esptool --chip esp32s3 --port /dev/ttyACM0 write_flash 0x0 <known-good-image.bin>
+  ```
+- For Reticulum/RNode boards, the equivalent manual recovery is
+  `archy-rnodeconf /dev/ttyACM0 --autoinstall` (or `/usr/local/bin/archy-rnodeconf`
+  if it's not on `PATH`) — it re-runs the same fetch+erase+flash+bootstrap
+  sequence the UI triggers.
+- If `esptool`/`archy-rnodeconf` are missing entirely, they should have been
+  installed by the last `self-update.sh` run — check
+  `sudo journalctl -u archipelago-update` for install failures, or install
+  `esptool` via `sudo apt-get install esptool` directly.
+- Once a fresh image is confirmed written, unplug/replug the radio (or wait
+  for the next detection poll) — the hot-swap modal re-probes automatically
+  and shows whatever firmware is actually on the board now.
+
+**Known incident (2026-07-23) — reconnect storm / device boot-loop after a
+failed flash**: a real Heltec V3 got stuck cycling "connect → partial
+handshake → drop" every 5-15s for 5+ minutes after a `mesh.flash-device`
+attempt failed with `Reading firmware download stream`. Root cause was two
+compounding issues, both now fixed:
+1. `spawn_mesh_listener`'s reconnect backoff (`core/archipelago/src/mesh/listener/mod.rs`)
+   reset to its 5s minimum any time the prior session had been `device_connected`
+   at all, even for under a second — so a device that connects-then-drops
+   repeatedly never actually backed off. Every retry's `open()` toggles
+   DTR/RTS, which resets many ESP32 boards' MCU (native-USB *and*
+   CP2102/CH340 auto-reset-circuit boards), so the aggressive retries were
+   themselves *causing* the boot loop, not just observing one. Fixed by only
+   resetting backoff when a session ran for at least `STABLE_SESSION_THRESHOLD`
+   (20s) — see that constant's doc comment.
+2. `mesh::flash::start_flash_job`'s post-completion handler auto-resumed the
+   listener unconditionally, even after a *failed* flash, immediately
+   re-entering the reconnect loop above with no cooldown. Fixed: on failure
+   the listener is now deliberately left stopped (reconnect manually via the
+   UI once the board is confirmed alive); on success there's a 5s settle
+   delay before resuming, so the board finishes booting from the flash
+   tool's own reset before Archipelago starts probing it again.
+3. Separately, the download itself was failing because `mesh::flash`'s HTTP
+   client had a blanket 30s request timeout that covered the *entire*
+   download (including streaming a 170MB Meshtastic zip), not just
+   connection setup — fixed with a per-chunk stall timeout instead of a
+   fixed total-transfer cap.
+
+If this symptom recurs (rapid repeating `mesh::serial: Opened serial
+port... Starting Meshcore handshake` lines in `journalctl -u archipelago`
+without a `LoRa firmware flash` job in progress), it's a NEW instance of the
+same class of bug, not the one above — check whether backoff is actually
+escalating (`Mesh session error: ... (retry in Xs)` — X should grow past 5s
+within a few cycles) before assuming it's flashing-related.
+
 ---
 
 ## General Maintenance

image-recipe/_archived/build-auto-installer-iso.sh

@@ -365,6 +365,11 @@ RUN apt-get update && apt-get -y full-upgrade && apt-get install -y --no-install
     ca-certificates \
     openssl \
     chrony \
+    iputils-ping \
+    esptool \
+    python3-venv \
+    binutils \
+    libpython3.13 \
     locales \
     console-setup \
     keyboard-configuration \

neode-ui/src/components/mesh/MeshDeviceSetupModal.vue

@@ -1,7 +1,7 @@
 <template>
   <BaseModal
     :show="show"
-    :title="step === 1 ? 'Mesh Radio Detected' : 'Apply Archipelago Settings'"
+    :title="step === 1 ? 'Mesh Radio Detected' : step === 2 ? 'Apply Archipelago Settings' : 'Flash Firmware'"
     max-width="max-w-lg"
     content-class="max-h-[90vh] overflow-y-auto"
     @close="dismiss"
@@ -96,9 +96,111 @@
         "Keep As Is" uses the radio exactly as it is — nothing on it is changed,
         and you can hot-swap radios any time.
       </p>
+      <button
+        class="w-full text-center text-white/40 hover:text-white/70 text-[11px] mt-3 underline underline-offset-2"
+        :disabled="!!connecting"
+        @click="openFlashStep"
+      >
+        Flash Firmware…
+      </button>
       <p v-if="error" class="text-xs text-red-400 mt-2">{{ error }}</p>
     </div>
 
+    <!-- Step 3: erase + reflash — destructive, opt-in only -->
+    <div v-else-if="step === 'flash'">
+      <!-- Once a job exists (started via startFlash), ALWAYS show the
+           progress/result view below — including on failure. The old
+           condition (`!active && stage !== 'done'`) was also true for a
+           FAILED job (active:false, stage:'failed'), which silently sent
+           the user back to this picker instead of showing the error. -->
+      <template v-if="!flashJob">
+        <p class="text-white/60 text-xs mb-3">
+          Downloads the latest firmware from upstream and writes it to
+          <span class="font-mono text-orange-300">{{ devicePath }}</span>.
+        </p>
+
+        <div class="space-y-4">
+          <div>
+            <label class="block text-sm text-white/80 mb-1">Firmware family</label>
+            <select v-model="flashFamily" class="w-full rounded-lg bg-white/[0.06] border border-white/10 text-white px-3 py-2 text-sm focus:outline-none focus:border-orange-400/60">
+              <option value="">Choose…</option>
+              <option value="meshcore">MeshCore</option>
+              <option value="meshtastic">Meshtastic</option>
+              <option value="reticulum">Reticulum RNode</option>
+            </select>
+          </div>
+          <div>
+            <label class="block text-sm text-white/80 mb-1">Board</label>
+            <select v-model="flashBoard" class="w-full rounded-lg bg-white/[0.06] border border-white/10 text-white px-3 py-2 text-sm focus:outline-none focus:border-orange-400/60">
+              <option value="">Choose…</option>
+              <option value="heltec-v3">Heltec LoRa 32 V3</option>
+              <option value="heltec-v4">Heltec LoRa 32 V4</option>
+            </select>
+            <p v-if="!boardAutoDetected" class="text-[11px] text-amber-400/80 mt-1">
+              Couldn't confirm the board automatically — double check before flashing.
+              Flashing the wrong board's image can brick it.
+            </p>
+          </div>
+        </div>
+
+        <div class="rounded-xl bg-red-500/10 border border-red-500/30 p-3 mt-4">
+          <label class="flex items-start gap-2 text-xs text-red-300">
+            <input type="checkbox" v-model="flashConfirmed" class="mt-0.5" />
+            <span>
+              This <strong>erases the entire chip</strong>, including any existing
+              keys, identity, and contacts. This cannot be undone.
+            </span>
+          </label>
+        </div>
+
+        <p v-if="error" class="text-xs text-red-400 mt-3">{{ error }}</p>
+
+        <div class="flex gap-2 mt-6">
+          <button class="glass-button px-4 py-2 rounded-lg text-sm" @click="step = 1">Back</button>
+          <button
+            class="flex-1 glass-button px-4 py-2 rounded-lg text-sm font-medium bg-red-500/80 hover:bg-red-500 text-white disabled:opacity-50"
+            :disabled="!flashFamily || !flashBoard || !flashConfirmed || starting"
+            @click="startFlash"
+          >
+            {{ starting ? 'Starting…' : 'Erase & Flash Now' }}
+          </button>
+        </div>
+      </template>
+
+      <!-- Progress -->
+      <template v-else>
+        <div class="text-center py-2">
+          <p class="text-white text-sm font-medium">{{ flashStageLabel }}</p>
+          <div class="mt-3 h-2 rounded-full bg-white/10 overflow-hidden">
+            <div
+              class="h-full bg-orange-400 transition-all"
+              :style="{ width: (flashJob?.percent ?? (flashJob?.stage === 'done' ? 100 : 8)) + '%' }"
+            ></div>
+          </div>
+          <p v-if="flashJob?.error" class="text-xs text-red-400 mt-3">{{ flashJob.error }}</p>
+        </div>
+        <div class="mt-3 rounded-xl bg-black/30 border border-white/10 p-2 h-32 overflow-y-auto font-mono text-[10px] text-white/50 leading-relaxed">
+          <div v-for="(line, i) in (flashJob?.log_tail ?? []).slice(-40)" :key="i">{{ line }}</div>
+        </div>
+        <div class="flex gap-2 mt-4">
+          <button
+            v-if="flashJob?.stage === 'downloading' && flashJob?.active"
+            class="glass-button px-4 py-2 rounded-lg text-sm"
+            @click="cancelFlash"
+          >
+            Cancel
+          </button>
+          <button
+            v-if="!flashJob?.active"
+            class="flex-1 glass-button glass-button-warning px-4 py-2 rounded-lg text-sm font-medium"
+            @click="closeFlashStep"
+          >
+            Done
+          </button>
+        </div>
+      </template>
+    </div>
+
     <!-- Step 2: our latest parameters, shown before anything is written -->
     <div v-else>
       <p class="text-white/60 text-xs mb-3">
@@ -185,7 +287,7 @@
 import { ref, computed, watch } from 'vue'
 import { useRouter } from 'vue-router'
 import BaseModal from '@/components/BaseModal.vue'
-import { useMeshStore, type MeshDeviceProbe, type MeshConfigureParams } from '@/stores/mesh'
+import { useMeshStore, type MeshDeviceProbe, type MeshConfigureParams, type FlashFirmwareFamily, type FlashBoard, type FlashJobStatus } from '@/stores/mesh'
 import { useAppStore } from '@/stores/app'
 import { LORA_REGIONS, regionByCode, suggestRegionFromLatLon, meshcorePlanFor } from '@/utils/loraRegions'
 import { resolveMeshDeviceImage } from '@/utils/meshDeviceImages'
@@ -194,7 +296,7 @@ const mesh = useMeshStore()
 const appStore = useAppStore()
 const router = useRouter()
 
-const step = ref<1 | 2>(1)
+const step = ref<1 | 2 | 'flash'>(1)
 const connecting = ref<false | 'keep' | 'setup'>(false)
 const error = ref('')
 const probing = ref(false)
@@ -259,7 +361,10 @@ const rfPreset = computed(() => {
 
 // (Re)probe + (re)apply presets each time a new device surfaces the modal
 watch([show, devicePath], async ([visible]) => {
-  if (!visible) return
+  if (!visible) {
+    stopFlashPoll()
+    return
+  }
   step.value = 1
   error.value = ''
   imageFailed.value = false
@@ -344,6 +449,118 @@ async function applySetup() {
     connecting.value = false
   }
 }
+
+// ─── Step 3: erase + reflash ─────────────────────────────────────────────
+const flashFamily = ref<FlashFirmwareFamily | ''>('')
+const flashBoard = ref<FlashBoard | ''>('')
+const flashConfirmed = ref(false)
+const starting = ref(false)
+const flashJob = ref<FlashJobStatus | null>(null)
+let flashPollTimer: ReturnType<typeof setInterval> | null = null
+
+const detectedInfo = computed(() =>
+  mesh.status?.detected_device_info?.find(d => d.path === devicePath.value)
+)
+
+// Mirrors mesh::flash::resolve_flash_board (core/archipelago/src/mesh/flash.rs)
+// exactly — matching on the display label was wrong: a Heltec V3's CP2102
+// bridge chip reports "CP2102 USB to UART Bridge Controller" in its USB
+// strings, not "Heltec", so meshDeviceImages.ts falls back to a generic
+// "LoRa radio (CP2102 serial)" label that never matched /v3/i, showing the
+// "couldn't confirm automatically" warning even though the backend CAN
+// safely auto-detect V3 via vid:pid. Heltec V4 deliberately has no entry
+// here, same reasoning as the backend: its vid:pid (303a:1001) is the
+// ESP32-S3's generic native-USB descriptor, not V4-specific, so it can't be
+// safely auto-matched and always requires manual selection.
+const resolvedFlashBoard = computed<FlashBoard | ''>(() => {
+  const info = detectedInfo.value
+  if (info?.vid?.toLowerCase() === '10c4' && info?.pid?.toLowerCase() === 'ea60') return 'heltec-v3'
+  return ''
+})
+
+const boardAutoDetected = computed(() => !!resolvedFlashBoard.value)
+
+const flashStageLabel = computed(() => {
+  switch (flashJob.value?.stage) {
+    case 'downloading': return 'Downloading firmware…'
+    case 'erasing': return 'Erasing chip…'
+    case 'writing': return 'Writing firmware…'
+    case 'autoinstalling': return 'Installing (rnodeconf)…'
+    case 'done': return 'Flash complete'
+    case 'failed': return 'Flash failed'
+    default: return ''
+  }
+})
+
+function openFlashStep() {
+  flashFamily.value = (probe.value?.kind as FlashFirmwareFamily) ?? ''
+  flashBoard.value = resolvedFlashBoard.value
+  flashConfirmed.value = false
+  flashJob.value = null
+  error.value = ''
+  step.value = 'flash'
+}
+
+function stopFlashPoll() {
+  if (flashPollTimer) {
+    clearInterval(flashPollTimer)
+    flashPollTimer = null
+  }
+}
+
+async function pollFlashStatus() {
+  try {
+    const status = await mesh.flashStatus()
+    flashJob.value = status
+    if (!status.active) {
+      stopFlashPoll()
+      if (status.done && !status.error) {
+        // Mirrors the unplug/replug hot-swap flow: re-probe so the details
+        // card reflects whatever firmware is actually on the board now.
+        const path = devicePath.value
+        probing.value = true
+        try {
+          probe.value = await mesh.probeDevice(path)
+        } catch {
+          probe.value = null
+        } finally {
+          probing.value = false
+        }
+      }
+    }
+  } catch {
+    stopFlashPoll()
+  }
+}
+
+async function startFlash() {
+  if (!flashFamily.value || !flashBoard.value || !flashConfirmed.value) return
+  starting.value = true
+  error.value = ''
+  try {
+    await mesh.flashDevice(devicePath.value, flashFamily.value, flashBoard.value)
+    flashJob.value = { active: true, stage: 'downloading', log_tail: [] }
+    stopFlashPoll()
+    flashPollTimer = setInterval(pollFlashStatus, 1500)
+  } catch (e) {
+    error.value = e instanceof Error ? e.message : 'Failed to start flashing'
+  } finally {
+    starting.value = false
+  }
+}
+
+async function cancelFlash() {
+  try {
+    await mesh.flashCancel()
+  } catch (e) {
+    error.value = e instanceof Error ? e.message : 'Failed to cancel'
+  }
+}
+
+function closeFlashStep() {
+  stopFlashPoll()
+  step.value = 1
+}
 </script>
 
 <style scoped>

neode-ui/src/stores/mesh.ts

@@ -55,6 +55,23 @@ export interface MeshDeviceProbe {
   max_contacts: number | null
 }
 
+export type FlashFirmwareFamily = 'meshcore' | 'meshtastic' | 'reticulum'
+export type FlashBoard = 'heltec-v3' | 'heltec-v4'
+export type FlashStage = 'downloading' | 'erasing' | 'writing' | 'autoinstalling' | 'done' | 'failed'
+
+/** Live progress for the one flash job that can run at a time. */
+export interface FlashJobStatus {
+  active: boolean
+  board?: FlashBoard
+  family?: FlashFirmwareFamily
+  path?: string
+  stage?: FlashStage
+  percent?: number | null
+  log_tail?: string[]
+  done?: boolean
+  error?: string | null
+}
+
 /** Params accepted by mesh.configure (superset of the status fields). */
 export interface MeshConfigureParams {
   enabled?: boolean
@@ -343,6 +360,32 @@ export const useMeshStore = defineStore('mesh', () => {
       timeout: 45000, // serial probes are slow (multi-firmware handshakes)
     })
   }
+  /** Available firmware version(s) for a family — v1 only ever returns
+   *  ["latest"], since firmware is always fetched from upstream at flash
+   *  time rather than pinned/bundled. */
+  async function flashListFirmware(family: FlashFirmwareFamily): Promise<string[]> {
+    const res = await rpcClient.call<{ versions: string[] }>({
+      method: 'mesh.flash-list-firmware',
+      params: { family },
+    })
+    return res.versions
+  }
+  /** Erase + reflash a detected radio. `board` is optional — omit it to let
+   *  the backend auto-resolve from the port's USB vid:pid; if that fails
+   *  (e.g. Heltec V4 not yet in the vid:pid table), it errors and the UI
+   *  must ask the user to pick the board explicitly. Always erases first. */
+  async function flashDevice(path: string, family: FlashFirmwareFamily, board?: FlashBoard): Promise<void> {
+    await rpcClient.call({
+      method: 'mesh.flash-device',
+      params: board ? { path, family, board } : { path, family },
+    })
+  }
+  async function flashStatus(): Promise<FlashJobStatus> {
+    return rpcClient.call<FlashJobStatus>({ method: 'mesh.flash-status' })
+  }
+  async function flashCancel(): Promise<void> {
+    await rpcClient.call({ method: 'mesh.flash-cancel' })
+  }
   let globalDetectTimer: ReturnType<typeof setInterval> | null = null
   /** App-wide light poll so the detected-device modal works on every page
    *  (the Mesh view's own 5s poll takes over while it is mounted). */
@@ -979,6 +1022,10 @@ export const useMeshStore = defineStore('mesh', () => {
     undismissedDetectedDevices,
     dismissDetectedDevice,
     probeDevice,
+    flashListFirmware,
+    flashDevice,
+    flashStatus,
+    flashCancel,
     startGlobalDetection,
     fetchPeers,
     fetchMessages,

reticulum-daemon/build.sh

@@ -47,11 +47,16 @@ if [ -n "$RNODECONF_SRC" ] && [ -f "$RNODECONF_SRC" ]; then
     # exit()/quit() builtins, which only exist in interactive Python (site.py
     # injects them) — a frozen app hits NameError right as it tries to quit
     # cleanly, after all the real work already succeeded. See
-    # pyi_rthook_exit_builtins.py.
+    # pyi_rthook_exit_builtins.py. A second hook fixes rnodeconf's board-flash
+    # step, which shells out to a bundled esptool.py via `sys.executable` —
+    # under a frozen binary that's the binary itself, not a real interpreter,
+    # so the flash subprocess call breaks. See
+    # pyi_rthook_fix_flasher_executable.py.
     .venv/bin/pyinstaller --onefile --name archy-rnodeconf --clean --noconfirm \
         --collect-submodules RNS \
         --collect-data RNS \
         --runtime-hook pyi_rthook_exit_builtins.py \
+        --runtime-hook pyi_rthook_fix_flasher_executable.py \
         -d noarchive \
         "$RNODECONF_SRC"
     echo "Built dist/archy-rnodeconf ($(du -h dist/archy-rnodeconf | cut -f1))"

reticulum-daemon/pyi_rthook_fix_flasher_executable.py

@@ -0,0 +1,34 @@
+# PyInstaller runtime hook — see build.sh.
+#
+# rnodeconf's own board-flashing code shells out to a bundled esptool.py as
+# `[sys.executable, flasher_path, "--chip", ..., "write_flash", ...]` (RNS's
+# rnodeconf.py, ~line 2794 as of RNS 1.3.5). That's correct for a normal
+# `python rnodeconf.py` invocation, but under a frozen PyInstaller binary
+# `sys.executable` is the frozen binary itself, not a real interpreter — so
+# the "subprocess" just re-invokes archy-rnodeconf's OWN argparse CLI with
+# esptool-shaped flags, which it doesn't recognize, and the flash step fails
+# immediately with "unrecognized arguments: --chip ...". Confirmed live
+# against a real Heltec V4 (2026-07-23): device selection, band selection,
+# and firmware download all worked; only the final `write_flash` subprocess
+# call broke this way.
+#
+# Fix: point sys.executable at a real Python interpreter that has rnodeconf's
+# own runtime deps available (esptool.py only needs pyserial, which RNS
+# already depends on) before any of rnodeconf's code runs. Prefer the build
+# venv this exact binary was frozen from — see build.sh — falling back to a
+# bare `python3` on PATH if that venv isn't present on this node.
+import os
+import sys
+
+if getattr(sys, "frozen", False):
+    _candidates = [
+        os.environ.get("ARCHY_RNODECONF_PYTHON", ""),
+        os.path.join(os.path.dirname(os.path.abspath(sys.argv[0])), "..", "reticulum-daemon", ".venv", "bin", "python3"),
+        os.path.expanduser("~/archy/reticulum-daemon/.venv/bin/python3"),
+    ]
+    for _candidate in _candidates:
+        if _candidate and os.path.isfile(_candidate):
+            sys.executable = _candidate
+            break
+    else:
+        sys.executable = "python3"

scripts/self-update.sh

@@ -84,6 +84,64 @@ if ! command -v nano >/dev/null 2>&1; then
     fi
 fi
 
+if ! command -v ping >/dev/null 2>&1; then
+    log "Installing iputils-ping..."
+    if sudo apt-get update -qq 2>>"$LOG_FILE" && sudo apt-get install -y -qq iputils-ping 2>>"$LOG_FILE"; then
+        ok "ping installed"
+    else
+        warn "Unable to install ping automatically; continuing update"
+    fi
+fi
+
+if ! command -v esptool >/dev/null 2>&1; then
+    log "Installing esptool for LoRa radio firmware flashing..."
+    if sudo apt-get update -qq 2>>"$LOG_FILE" && sudo apt-get install -y -qq esptool 2>>"$LOG_FILE"; then
+        ok "esptool installed"
+    else
+        warn "Unable to install esptool automatically; radio firmware flashing will be unavailable"
+    fi
+fi
+
+# Debian's esptool package (4.7.0+dfsg-0.1) ships without the precompiled
+# esp32s3 "stub flasher" blob (stripped for DFSG compliance — no
+# buildable-from-source path Debian could verify). Without it, esptool's
+# normal stub-loader mode fails outright (FileNotFoundError), and the ROM
+# bootloader fallback (--no-stub) doesn't implement a full-chip erase at
+# all — confirmed live 2026-07-23 flashing a real Heltec V4, both ways.
+# Fetching the exact same file from the matching upstream esptool release
+# tag restores full (and correct) flashing behavior — it's the same
+# open-source codebase, just the one blob Debian's packaging couldn't
+# include.
+if command -v esptool >/dev/null 2>&1; then
+    STUB_DIR="/usr/lib/python3/dist-packages/esptool/targets/stub_flasher"
+    STUB_FILE="$STUB_DIR/stub_flasher_32s3.json"
+    if [ ! -f "$STUB_FILE" ]; then
+        log "Fetching esptool's esp32s3 stub flasher (missing from the Debian package)..."
+        ESPTOOL_VERSION=$(esptool version 2>/dev/null | tail -1 | tr -d ' \t')
+        if [ -n "$ESPTOOL_VERSION" ] && sudo curl -fsSL -o "$STUB_FILE" \
+            "https://raw.githubusercontent.com/espressif/esptool/v${ESPTOOL_VERSION}/esptool/targets/stub_flasher/stub_flasher_32s3.json" \
+            2>>"$LOG_FILE"; then
+            sudo chmod 644 "$STUB_FILE"
+            ok "esp32s3 stub flasher installed"
+        else
+            sudo rm -f "$STUB_FILE" 2>/dev/null
+            warn "Unable to fetch esp32s3 stub flasher; LoRa firmware flashing will be unavailable"
+        fi
+    fi
+fi
+
+# Build-time prerequisites for reticulum-daemon/build.sh's PyInstaller step
+# below (discovered the hard way: ensurepip needs python3-venv, and
+# PyInstaller itself needs objdump + libpython3.13.so at build time — none
+# of these are pulled in by a bare `python3` package on Debian trixie).
+for pkg in python3-venv binutils libpython3.13; do
+    if ! dpkg -s "$pkg" >/dev/null 2>&1; then
+        log "Installing $pkg (reticulum-daemon build prerequisite)..."
+        sudo apt-get update -qq 2>>"$LOG_FILE" && sudo apt-get install -y -qq "$pkg" 2>>"$LOG_FILE" \
+            || warn "Unable to install $pkg automatically; reticulum-daemon tools build may fail"
+    fi
+done
+
 # Fetch latest
 log "Fetching from origin..."
 git fetch origin main --quiet 2>>"$LOG_FILE"
@@ -155,6 +213,30 @@ sudo cp "$BUILT_BIN" "$INSTALL_BIN"
 sudo chmod +x "$INSTALL_BIN"
 ok "Backend installed"
 
+# Build + install reticulum-daemon tools (archy-reticulum-daemon, archy-rnodeconf).
+# Non-fatal: archipelago falls back to its dev venv path if the packaged
+# binaries aren't present, so a missing/failed build here degrades mesh
+# Reticulum support rather than breaking the update. This mirrors
+# deploy-to-target.sh's existing manual-deploy step, which until now was the
+# only path that ever installed these — a node that only ever received OTA
+# self-updates had neither binary.
+if [ -f "$REPO_DIR/reticulum-daemon/build.sh" ]; then
+    log "Building reticulum-daemon tools (archy-reticulum-daemon, archy-rnodeconf)..."
+    if (cd "$REPO_DIR/reticulum-daemon" && ./build.sh) 2>>"$LOG_FILE"; then
+        for tool in archy-reticulum-daemon archy-rnodeconf; do
+            if [ -f "$REPO_DIR/reticulum-daemon/dist/$tool" ]; then
+                sudo cp "$REPO_DIR/reticulum-daemon/dist/$tool" /usr/local/bin/
+                sudo chmod +x "/usr/local/bin/$tool"
+                ok "$tool installed"
+            else
+                warn "$tool not built — leaving existing /usr/local/bin/$tool (if any) in place"
+            fi
+        done
+    else
+        warn "reticulum-daemon tools build failed — continuing without updating them"
+    fi
+fi
+
 # Build frontend
 log "Building Vue frontend (production)..."
 cd "$FRONTEND_DIR"