ND-300 Network Diagnostic

Cross-platform network diagnostic tool for Windows, macOS, and Linux. Includes SpeedQX, a standalone eight-provider speed test (SpeedQX Methodology v4).

Features

Two operating modes: User mode (clean summary) and Technician mode (deep diagnostics)
8 core diagnostics: adapters, interfaces, gateway, DNS, public IP, latency, speed test, port connectivity
25 deep diagnostics (technician mode): ARP (+ gateway health), routing, connections, listening ports, DHCP, protocol stats, adapter hardware, proxy (+ PAC/WPAD), VPN, firewall, DNS cache, IPv6 (+ real v6 fetch), MTU (+ path-MTU probe), connection states, real bufferbloat (loaded latency during saturation), reverse DNS, TLS inspection, traffic counters, route path (traceroute analysis), sustained packet loss, NAT/CGNAT analysis, Wi-Fi link quality, DNS resolver benchmark (+ hijack/DNSSEC checks), captive portal detection, clock sync (NTP)
Diagnostic-driven nd300 fix — runs the diagnostics, identifies which checks failed, and applies only the recovery actions that target those specific failures. Clean and latency-only networks are advisory/no-op, DNS repair is staged from safest to most invasive, and medium/high-risk steps require confirmation. Re-tests after each step and repeats until everything passes or no further actions remain.
Eight-source SpeedQX engine — Cloudflare + M-Lab NDT7 + LibreSpeed + fast.com (Netflix) + M-Lab MSAK + Apple networkQuality + CacheFly + Vultr, using Methodology v4 capacity/consensus merging, agreement, confidence intervals, PDV jitter, and RPM. ND300's core diagnostic keeps the shorter Cloudflare + NDT7 run; standalone speedqx uses all eight.
Channel-preserving self-update — nd300 update / speedqx update proves how the running copy was installed and updates through that same channel: Cargo stays Cargo, a managed macOS/Linux archive stays a managed archive, a macOS PKG reopens its exact signed DMG/PKG channel, and each Windows MSI/EXE edition downloads its exact matching installer. Unknown, conflicted, local-build, and package-manager ownership is refused instead of guessed. Downloads are pinned to one exact release and verified before the two-binary transaction; a failure retains the old install and points to an exact matching artifact plus the versionless install page.
SpeedQX standalone speed test binary — all 8 providers (Methodology v4: capacity + consensus merge, I² agreement, PDV jitter, RPM) with per-provider breakdown and real-time progress; --fast for the quick 3-provider early-stopping run, --skip-msak/--skip-apple to trim the full run
Bufferbloat detection with grade scoring (A+ through F)
JSON output for scripting and automation
Unicode box-drawing table rendering with ASCII fallback
Color-coded status indicators (OK/Warn/Fail/Skip)
Cross-platform — native support for Windows, macOS, and Linux

Installation

macOS preferred installer (universal PKG-in-DMG)

Download nd300-universal-apple-darwin.dmg from the latest release, open nd300.pkg, and follow Apple Installer. The versionless universal download installs both commands system-wide in /usr/local/bin and works natively on Apple Silicon and Intel. The DMG and nested PKG are Developer ID signed, notarized, and stapled; installation uses the normal macOS authorization prompt.

A deliberate fresh PKG is the newest channel choice, including a same-version repair or explicit downgrade. It replaces the system pair and consolidates a receipt-proven managed archive in the standard Cargo home. Automatic updates remain latest-only and never change a proven installation channel.

Shell (macOS/Linux alternative)

curl --proto '=https' --tlsv1.2 -LsSf https://github.com/QubeTX/qube-network-diagnostics/releases/latest/download/nd300-installer.sh | sh

PowerShell (Windows)

powershell -ExecutionPolicy Bypass -c "irm https://github.com/QubeTX/qube-network-diagnostics/releases/latest/download/nd300-installer.ps1 | iex"

Windows installers (MSI + EXE, Global + Corporate)

Four first-class Windows installers are attached to every release. All four install both nd300.exe and speedqx.exe and add the install dir to your PATH. A fresh official installer represents your latest choice within the same Windows install scope: it removes a proven conflicting ND300 format before claiming ownership, or fails without claiming success when Windows permissions or scope make that unsafe.

Edition	Scope	Admin (UAC)?	Installs to	Download
Global MSI	Per-machine	Yes	`C:\Program Files\nd300\bin\`	`nd300-x86_64-pc-windows-msvc.msi`
Corporate MSI	Per-user	No	`%LocalAppData%\Programs\nd300\bin\`	`nd300-x86_64-pc-windows-msvc-corporate.msi`
Global EXE	Per-machine	Yes	`C:\Program Files\nd300\bin\`	`nd300-x86_64-pc-windows-msvc-setup.exe`
Corporate EXE	Per-user	No	`%LocalAppData%\Programs\nd300\bin\`	`nd300-x86_64-pc-windows-msvc-corporate-setup.exe`

Corporate editions install per-user with no admin prompt — ideal for locked-down corporate machines where you can't elevate.
Each installer writes a small HKCU\Software\ND300\InstallSource marker only after setup commits successfully, and removes it on uninstall only when it still names that installer. The marker helps nd300 update choose its matching in-place installer, but ND300 also proves ownership against the normalized Add/Remove Programs record; a Cargo-path binary or proven registered owner overrides a contradictory stale marker (see Self-Update).
Each installer has a .sha256 sidecar; nd300 update verifies it before running the downloaded installer (refuse-on-mismatch).
The cargo-dist PowerShell installer above remains available and installs into Cargo's bin directory.

One install at a time — automatic, scope-safe consolidation. A fresh MSI/EXE proves and uninstalls a conflicting registered ND300 format in the same per-user or per-machine scope without shell-expanding registry commands. Windows Installer cannot safely major-upgrade across those two scopes, so an opposite-scope owner is refused before any mutation; uninstall it first or choose the current installer in the same scope. Each installer also offers two clean-up checkboxes, both checked by default:

Remove an older Cargo-installed copy — deletes a shadowing nd300/speedqx in your ~\.cargo\bin (a prior cargo install copy usually wins on PATH otherwise). A non-running pair is removed before setup returns; a genuinely locked image uses the trusted retry helper and is reported as scheduled, never synchronously removed. If that retry cannot be armed, the primary old command is retained and cleanup is reported incomplete instead of leaving an unreported partial pair. Your Rust toolchain is never touched — cargo.exe, rustup.exe, and the .cargo\bin PATH entry are left exactly as they were.
Also remove the other edition — performs advisory, file-only cleanup of an unregistered stale Global/Corporate binary pair after ownership preflight.

The fallback clean-up only ever removes nd300.exe/speedqx.exe, never Cargo, Rustup, the Cargo PATH entry, the running replacement, or anything in Downloads. Supported registered takeover removes the prior binary pair, Add/Remove Programs entry, its correct user/system PATH entry, and stale marker together. MSI product codes are accepted only after Windows Installer itself proves that they belong to ND300's canonical UpgradeCode. If scope or permissions make takeover unsafe, setup stops with guidance rather than leaving two channels and pretending consolidation succeeded. These helpers are installer-only; you never need to run them by hand.

Cargo

cargo install nd300

Older installed copies that still request nd-300-installer.sh or nd-300-installer.ps1 are supported by compatibility aliases on every new GitHub release, so the legacy updater path can still reach the current installers.

Cargo itself cannot run ND300-specific post-install hooks for unrelated old install locations. A Cargo-managed nd300 update stays on Cargo and safely retires its running executable, but a deliberate switch to bare cargo install should be preceded by nd300 uninstall if a Windows installer currently owns the command. The official MSI/EXE and PowerShell entrypoints can perform their own scope-safe fresh-channel takeover automatically.

From Source

git clone https://github.com/QubeTX/qube-network-diagnostics.git
cd qube-network-diagnostics
cargo build --release

Usage

nd300 — Network Diagnostic

As of v3.0.0, every action command is available either as a subcommand or as a flag — both forms are first-class and produce identical behavior. Pick whichever you prefer.

# Default user mode — clean summary
nd300

# Technician mode — full deep diagnostics
nd300 -t

# Change DNS configuration (interactive)
nd300 dns          # subcommand form (recommended); on success continues to diagnostics
nd300 -d           # legacy flag form (still supported); identical behavior

# Diagnostic-driven fix loop (subcommand form, recommended)
nd300 fix

# Same thing — legacy flag forms (still supported)
nd300 -f
nd300 --fix

# Auto-confirm medium-risk prompts (does NOT bypass high-risk Y/N)
nd300 fix --yes
nd300 -f -y

# Skip the speed test for faster execution
nd300 --fast
nd300 fix --fast

# JSON output for scripting
nd300 --json
nd300 fix --json    # JSON works after subcommands too (global flag)

# ASCII characters instead of Unicode
nd300 --ascii

# Disable colored output
nd300 --no-color

# Custom report title
nd300 -T "Office Network Check"

# Custom speed test duration per provider (seconds)
nd300 --speed-duration 20

# Self-update — both forms work
nd300 update
nd300 --update

# Reset DNS cache — both forms work
nd300 clear-dns
nd300 --clear-dns
nd300 -c

# Uninstall — both forms work
nd300 uninstall
nd300 --uninstall

# Show help
nd300 --help
nd300 fix --help    # subcommand-specific help

speedqx — Standalone Speed Test

# Full eight-provider speed test (Cloudflare + NDT7 + MSAK + LibreSpeed + fast.com + CacheFly + Vultr + Apple)
speedqx

# Custom duration per direction (60s download + 60s upload per provider)
speedqx --duration 60

# Override fast.com duration (defaults to "auto")
speedqx --fastcom-duration 30

# Classic 4-provider run
speedqx --skip-msak --skip-apple

# JSON output
speedqx --json

# Quick test with shorter duration
speedqx --duration 10 --latency-probes 5

Example Output

╔══════════════════════════════════════════════════════════════╗
║                   ND-300 Network Diagnostic                 ║
╠══════════════════════════════════════════════════════════════╣
║ Category         │ Status │ Details                         ║
╠══════════════════╪════════╪═════════════════════════════════╣
║ Network Adapters │  OK    │ Wi-Fi (connected)               ║
║ IP Configuration │  OK    │ 192.168.1.42/24                 ║
║ Default Gateway  │  OK    │ 192.168.1.1                     ║
║ DNS Resolution   │  OK    │ 1.1.1.1, 8.8.8.8               ║
║ Public IP        │  OK    │ 203.0.113.45 (Cloudflare)       ║
║ Latency          │  OK    │ 12ms avg (1.1.1.1)             ║
║ Speed Test       │  OK    │ ↓ 245 Mbps  ↑ 48 Mbps          ║
║ Port Check       │  OK    │ 8/8 reachable                   ║
╚══════════════════╧════════╧═════════════════════════════════╝

Command Line Options

Flag	Description
`-t, --tech`	Technician mode — show full technical report with deep diagnostics
`-T, --title <TITLE>`	Custom title for the report header
`--json`	Output results as JSON
`--ascii`	Use ASCII characters instead of Unicode box-drawing
`--no-color`	Disable colored output
`--fast`	Skip the speed test (faster execution)
`--speed-duration <SECS>`	Speed test duration in seconds, per direction per provider (default: 15, min: 4)
`--verbose`	Show additional debug/trace information
`-d, --dns`	Change DNS servers and verify connectivity (requires elevated privileges)
`-f, --fix`	Run the diagnostic-driven triage / fix loop (requires elevated privileges). Equivalent to `nd300 fix`.
`-c, --clear-dns`	Flush the system DNS cache. Equivalent to `nd300 clear-dns`.
`--uninstall`	Remove nd300 from the system. Equivalent to `nd300 uninstall`.
`--update`	Check for updates and install the latest version. Equivalent to `nd300 update`.
`-y, --yes`	Auto-confirm medium-risk prompts when running the fix flow. Does not bypass high-risk Y/N.
`-h, --help`	Print help
`-v, --version`	Print version

Subcommands

Subcommand	Equivalent flag	Description
`nd300 dns`	`nd300 -d` / `nd300 --dns`	Change DNS servers and verify connectivity (semi-exit-early: exits on failure, continues to diagnostics on success)
`nd300 fix [-y]`	`nd300 -f` / `nd300 --fix`	Diagnostic-driven triage and recovery loop
`nd300 update`	`nd300 --update`	Self-update to the latest release
`nd300 clear-dns`	`nd300 -c` / `nd300 --clear-dns`	Flush the DNS cache and exit
`nd300 uninstall`	`nd300 --uninstall`	Uninstall nd300 from this system

SpeedQX Options

Flag	Description
`--json`	Output results as JSON
`--ascii`	Use ASCII characters instead of Unicode box-drawing
`--no-color`	Disable colored output
`--duration <VALUE>`	Test duration per direction for CF/NDT7/LS/MSAK/Apple: seconds or "auto" (default: 30)
`--fastcom-duration <VALUE>`	Test duration per direction for fast.com: seconds or "auto" (default: auto)
`--latency-probes <N>`	Number of latency probes (default: 20)
`--skip-msak`	Skip the M-Lab MSAK multi-stream provider
`--skip-apple`	Skip the Apple networkQuality provider
`--update`	Check for updates and install the latest version
`-v, --version`	Print version
`-h, --help`	Print help

User Mode vs Technician Mode

User mode (default) runs 8 core diagnostics and presents a clean summary table. Ideal for quick network health checks.

Technician mode (-t) runs all 8 core diagnostics plus 25 additional deep diagnostic modules. Produces a detailed technical report with per-module breakdowns, suitable for troubleshooting and support workflows. A full technician run takes ~2–4 minutes — the long probes (traceroute, sustained packet loss, loaded bufferbloat) are doing real work.

Diagnostics Covered

Core Diagnostics (both modes)

Network Adapters
IP Configuration / Interfaces
Default Gateway
DNS Resolution
Public IP
Latency
Speed Test (Cloudflare + M-Lab NDT7 in nd300; all 8 providers in SpeedQX)
Port Connectivity

Deep Diagnostics (technician mode only)

ARP Table + Gateway Health
Routing Table
Active Connections
Listening Ports
DHCP Lease Info
Protocol Statistics
Adapter Hardware Details
Proxy Detection (+ PAC validation, WPAD discovery)
VPN Detection
Firewall Status
DNS Cache
IPv6 Connectivity (+ real HTTPS-over-v6 fetch, v4-vs-v6 comparison)
MTU per Interface + Path-MTU Discovery
Connection State Summary
Bufferbloat (real loaded-latency measurement, per-direction grades)
Reverse DNS
TLS Inspection
Traffic Counters
Route Path (traceroute with LAN/ISP/backbone analysis)
Sustained Packet Loss (30 probes × 3 targets)
NAT Analysis (double-NAT, CGNAT detection)
Wi-Fi Link Quality (signal, channel, band, PHY, security)
DNS Resolver Benchmark (+ NXDOMAIN-hijack and DNSSEC checks)
Captive Portal Detection
Clock Sync (SNTP offset measurement)

macOS accuracy notes

ND300 builds one topology view from the default route, current interface flags, network-service/hardware-port mappings, and assigned addresses. The active count includes usable physical uplinks, not loopback, AWDL/LLW, dormant tunnels, or link-local-only devices. If a VPN owns the default route, the logical tunnel and underlying physical uplink are described separately.

Core mode never waits for optional Wi-Fi radio metadata. Technician mode uses a bounded system_profiler query, with a text fallback for older supported macOS versions; it reads only the connected network and treats a privacy-redacted SSID as unavailable. VPN reporting correlates macOS VPN configuration, network state, addresses, and routes rather than calling every utun device a VPN. IPv6 ULA is reported separately, and dual_stack means both IPv4 and IPv6 connectivity were actually verified.

TLS inspection reports clear, detected, or inconclusive evidence and populates the issuer only after a bounded Rust TLS handshake. DNSSEC is reported as validating only when a valid signed control resolves and the deliberately invalid control does not. If macOS suppresses protocol counters, that section is omitted instead of presenting unknown values as zero.

Fix Flow (`nd300 fix` / `nd300 -f`)

The fix flow runs a diagnostic-driven triage loop: it tests the network, looks at what actually failed, applies only the recovery actions that target those specific failures, re-tests, and repeats. Requires elevated privileges (sudo on macOS/Linux, Administrator on Windows).

A clean network completes nd300 fix in under 8 seconds and applies zero actions. Latency-only findings are reported as advisory because ICMP can be rate-limited or deprioritized by healthy networks. A real failure usually clears in 1–2 iterations.

How it works

1. Run baseline diagnostics
2. If everything passes → done.
3. Look at which specific diagnostics failed.
4. Group them by root cause (e.g. interface-down ⇒ skip DNS/gateway/IP — they cascade).
5. Pick the safest justified action that targets a remaining failure and apply it.
6. Wait for the system to stabilize.
7. Re-run the diagnostics.
8. Repeat until everything passes, or no further actions are available.

The loop is bounded by three independent caps so it always terminates:

≤ 6 iterations
≤ 4 minutes wall clock
Per-action attempt cap (typically 1 — failed actions are not retried)

Action ladder

Actions are tried by evidence and risk: cheap first, reversible first, and only when the current failure set justifies the action. DNS repair is intentionally staged so the tool flushes caches and restores router-provided DNS before considering a public DNS change.

Cost / risk	Action	Targets
Cheap / Low	Flush DNS cache	DNS
Cheap / Low	Reset DNS to router defaults	DNS
Cheap / Low	Switch DNS to Cloudflare 1.1.1.1	DNS, only after safer DNS-specific fixes fail
Cheap / Low	Flush ARP cache	Gateway
Medium / Low	Restart networking services	DNS, gateway, public IP
Medium / Low	Renew DHCP lease	Gateway, public IP, adapters, interfaces
Medium / Medium	Temporarily disable consumer VPNs	Public IP, DNS; interactive confirmation required
Expensive / Medium	Restart the network adapter	Adapters, interfaces, gateway, DNS, public IP
Expensive / High	Deep stack reset (Winsock / TCP-IP / IPv6 on Windows; gated network-service cycle on macOS; recreate NetworkManager profile on Linux)	Last-resort recovery

Enterprise VPNs (Cisco AnyConnect, Zscaler, Palo Alto / GlobalProtect, F5, Check Point, Juniper) are never auto-disabled. Consumer VPN disable is also skipped in JSON or non-interactive mode, even with --yes, because the tool cannot safely guide re-enable/recovery steps there. Other medium-risk actions such as DHCP reset, service restart, adapter restart, and public-DNS changes are skipped in JSON or non-interactive mode unless --yes can safely auto-confirm the medium-risk prompt. High-risk actions are never auto-confirmed.

Confirmation prompts

Medium-risk actions explain what they will change and require confirmation unless --yes is provided. The deep stack reset is high-risk and is always gated behind a structured plain-language prompt:

┌─ Escalating: Reset Windows networking stack ──────────────────────────────
Why I want to do this:
  Gateway and DNS are still failing after DHCP renew and ARP flush.
  Resetting the networking stack rebuilds Windows' TCP/IP, Winsock,
  and IPv6 catalogs from scratch — the standard fix when simpler
  steps haven't recovered the connection.

What will happen:
  • You will lose internet for ~10–15 seconds.
  • Open VPN sessions and SSH connections will drop.
  • A reboot is recommended afterward; nd300 will remind you at the end.

Reversible: requires reboot to fully revert
Typical duration: 10–15 seconds

Continue? Type 'y' to proceed, anything else to skip:

--yes does not bypass high-risk prompts — they always require an explicit y. Anything else (including a blank Enter) is treated as N. In --json / non-interactive contexts, high-risk actions are skipped, not auto-applied, with a clear marker in the report.

macOS deep-reset safety

ND300 no longer deletes and recreates a macOS network service. That older design could lose service identity/order and only partially restore Wi-Fi, DNS, search, proxy, or addressing state when any command failed. The deletion path, Wi-Fi password retrieval, and SSID scanning have been removed.

The replacement maps the exact enabled physical service and cycles it off/on. It registers re-enable before mutation, preserves DNS servers and search domains exactly, and requires the service to be enabled with the expected physical route and reachability before the restore is considered complete. DHCP renewal likewise runs only when that service is already configured for DHCP; Manual, BootP, static, disabled, virtual, missing, or ambiguous services are not changed.

The macOS service cycle is fail-closed and unavailable in this release build until its destructive acceptance test passes under an independent, offline-capable watchdog on a disposable Mac VM or sacrificial service. A Mac whose control session depends on the Wi-Fi being cycled is not a safe acceptance host: losing Wi-Fi would also lose the recovery operator. Until the gate is deliberately enabled after that proof, ND300 gives safe lower-risk/manual guidance and does not cycle the service.

Hard-block detection

Some failure shapes can't be auto-fixed. The loop short-circuits cleanly with guidance instead of thrashing:

No physical link — no cable / Wi-Fi.
ISP outage shape — local network healthy, public internet failing.
Enterprise VPN active — diagnostics shaped by a managed VPN we won't disable.

Fix Report

Every run produces a Markdown report at ~/Downloads/nd300-fix-report-YYYYMMDD-HHMMSS.md:

Verdict — Fixed, Partially fixed, Couldn't fix, Cannot fix from here, Timed out, or Stopped at your request.
Baseline diagnostics — full table snapshot before any action ran.
Iteration timeline — for each loop pass: which actions ran, captured stdout/stderr/exit/duration, and the diagnostic delta after.
Final diagnostics — same table as baseline so you can see what changed.
Environment — OS, version, elevation status, VPNs detected.
What to try next — concrete suggestions when the fix didn't fully succeed (restart router, contact ISP, check for driver updates, etc.).

When the command is elevated through sudo, ND300 validates the invoking user from numeric account data and writes the report to that user's Downloads folder, not /var/root. Reports are created atomically with private 0600 permissions and correct ownership. Restore operations run newest-first after Ctrl-C, SIGTERM, or SIGHUP, and reverted is reported only after state verification.

In JSON mode (nd300 fix --json), the schema reports the same data as outcome, iterations, applied_actions[], remaining_failures[], hard_block, and report_path.

DNS Configuration (`nd300 dns`)

nd300 dns (or the legacy flag nd300 -d / --dns) provides a standalone way to change your DNS configuration. Requires elevated privileges. The subcommand and flag are identical: both are semi-exit-early — they exit on failure, and on success fall through to running standard diagnostics so you can immediately confirm the change improved connectivity.

Providers:

Cloudflare (recommended) — 1.1.1.1 (privacy-focused)
Google — 8.8.8.8 (reliability)
NextDNS — Encrypted DNS with filtering (requires config ID)
Automatic — Reset to system default (DHCP)
Hybrid (not recommended) — Cloudflare + Google

NextDNS encryption by platform:

Windows — DNS-over-HTTPS via netsh DoH template registration
Linux — DNS-over-TLS via systemd-resolved (falls back to plain IPs via nmcli)
macOS — NextDNS CLI client (nextdns install/activate), plain IPs if CLI not installed

After setting DNS, the tool verifies both DNS resolution and HTTP connectivity. On macOS it first captures the exact prior DNS servers and search domains; if capture fails, no change is made, and if verification fails the exact snapshot is restored and read back before reverted: true is reported. Windows/Linux retain their automatic-DNS rollback for a failed provider change. On success, full diagnostics run to confirm network health.

Man Pages (Linux/macOS)

Man pages are generated at build time and included in release archives. To install after building from source:

macOS (user-writable, no sudo or mandb):

mkdir -p "$HOME/.local/share/man/man1"
cp man/nd300.1 man/speedqx.1 "$HOME/.local/share/man/man1/"
export MANPATH="$HOME/.local/share/man:${MANPATH:-}"

Add the MANPATH export to ~/.zprofile if you want it in every new shell.

Linux system-wide:

sudo install -Dm644 man/nd300.1 /usr/local/share/man/man1/nd300.1
sudo install -Dm644 man/speedqx.1 /usr/local/share/man/man1/speedqx.1

Then use man nd300 or man speedqx to view documentation.

Building from Source

git clone https://github.com/QubeTX/qube-network-diagnostics.git
cd qube-network-diagnostics
cargo build --release

Binaries will be at target/release/nd300 and target/release/speedqx (or .exe on Windows).

Self-Update

Both binaries support self-updating to the latest release. Either form works:

nd300 update          # subcommand form (recommended)
nd300 --update        # legacy flag form (still supported)
speedqx update
speedqx --update

The updater follows a prove, pin, verify, replace contract:

Checks the latest release on GitHub. If you're already on it, exits 0 with no action.
Proves the running installation channel. Cargo registry metadata selects only bounded cargo install nd300 --version =<resolved> --force --locked as the validated invoking user. A valid Unix receipt selects only the native archive transaction. On macOS, an exact root-owned /usr/local/bin pair, Apple package receipt, payload inventory, version, and hash-bound install metadata select only the DMG/PKG installer transaction. Windows registry, path, marker, and Cargo evidence select exactly one of Cargo, standalone, or MSI/EXE × Global/Corporate. A conflict or unknown owner changes nothing.
Public commands and download links use releases/latest; after the latest tag is resolved, every archive, installer, checksum, and verification step is pinned to that one immutable tag. No transaction mixes moving “latest” bytes.
A managed macOS/Linux archive fetches the exact compile-target .tar.xz plus required .sha256 sidecar with time and size limits; verifies SHA-256 in ND300; and allowlist-extracts only the two expected regular files. Absolute paths, traversal, symlinks, hardlinks, duplicates, and unexpected layouts are rejected.
Executes both staged programs with --version. On macOS it additionally requires the pinned Developer ID certificate, Team ID M9D5379H93, identifiers com.qubetx.nd300 and com.qubetx.speedqx, hardened runtime, and timestamp.
Managed archives atomically replace both binaries with backups. A proven macOS package instead downloads and verifies the exact-tag versionless DMG, validates the outer Developer ID Application signature and nested Developer ID Installer signature plus both notarization tickets, then opens Apple Installer and verifies the new package receipt and pair after it closes. Cancellation or failure retains the prior installation as the recovery point.
On Windows, a Cargo-bin path wins over any stale installer marker. Otherwise ND300 proves a matching MSI/Inno owner from Add/Remove Programs and its normalized install location before selecting one of the four installer-aware update paths. MSI identity is accepted only when Windows Installer enumerates the product under ND300's canonical UpgradeCode; the marker is only a compatible fallback. The two running-image files are renamed to versioned, allowlisted siblings before replacement, restored on failure, and removed after the old process exits.
There is no cross-channel fallback after a failed update. The old installation remains authoritative, pretty and --json output explain the failure, and https://reports.qubetx.com/nd300#install is provided for a fresh download.

Unix uninstall is origin-aware too. Cargo-managed installs use cargo uninstall nd300; invocation through an ordinary symlink removes only the symlink; a cargo-dist layout requires its validated receipt. A receipt-proven macOS PKG requests Apple authorization, removes only its hash-bound system pair and metadata, and forgets com.qubetx.nd300.pkg. ND300 refuses to modify unknown, local-build, Homebrew/MacPorts, or other package-manager-owned locations and prints manual guidance instead.

Windows installer-aware self-update

If you installed via one of the four first-class Windows installers (MSI/EXE × Global/Corporate — see Installation), nd300 update matches the running executable to its normalized HKCU/HKLM Add/Remove Programs record and downloads the matching installer for an in-place upgrade — rather than switching you to a different installer/format. The HKCU\Software\ND300\InstallSource marker and known install path are fallbacks, not unconditional authority. A binary in .cargo\bin, or a single proven registered owner, overrides a contradictory stale marker.

Windows locks a running executable against overwrite but permits an in-place rename. Before replacement, the updater/installer moves only nd300.exe and speedqx.exe to versioned *.update-old-* siblings. MSI performs that move in its rollback-aware transaction; Inno and the hardened cargo-dist script restore the pair if their copy phase fails. The new allowlisted helper removes the retired images immediately or after the old updater exits, so no reboot is required merely to replace the running command.

Before running a downloaded MSI/EXE, the updater pins both the installer and its .sha256 sidecar to the already-resolved release tag and verifies the download against it (refuse-on-mismatch) — defending against a corrupted download or a network MITM (corporate TLS-interception proxies, hostile WiFi). After the installer exits, it re-runs --version to confirm the file replacement actually took effect (and surfaces the reboot-required case honestly if Windows scheduled a deferred replace).

Updates preserve channel; fresh installs may change format within one scope. An MSI update stays the same MSI edition, an Inno update stays the same EXE edition, Cargo stays Cargo, and standalone stays standalone. A deliberate fresh official Windows install treats the selected package as the latest user intent and may replace a proven MSI/EXE owner in the same per-machine or per-user scope. A raw per-user ↔ per-machine switch is refused before mutation because Windows Installer cannot major-upgrade across contexts and an elevated installer must never execute a user-writable uninstaller. Uninstall the old scope first, or choose the desired format in that same scope. The Global MSI also repairs the pre-v3.1 C:\Program Files\nd-300\bin system-PATH entry after a successful migration while preserving every unrelated entry and registry value type. Default Cargo-copy cleanup remains narrowly file-only and never removes the Rust toolchain.

Windows uninstall is ownership-aware as well. For a proven MSI/Inno install, nd300 uninstall starts that registered uninstaller directly from a validated product code or uninstaller path—never a shell-expanded registry command—so the binary pair, Add/Remove Programs registration, correct user/system PATH entry, and installer marker are removed together. Cargo and portable copies keep the strict two-binary allowlist and never remove Cargo, Rustup, or the Cargo PATH.

Versioning is prerelease-aware: a prerelease of an upcoming version is treated as newer than the previous stable patch, and a stable release is newer than its own prerelease. GitHub's unauthenticated rate-limit case (60 requests/hour per IP) is named explicitly so you know to just wait.

Current releases publish the canonical nd300-installer.sh and nd300-installer.ps1 assets plus legacy nd-300-installer.* aliases for older installed copies.

Update JSON output

In --json mode, stdout contains exactly one response object; download, verification, and installer progress use stderr. The response includes "strategy" (the precise variant that ran or was attempted) and, on failure, an "attempts" array. The legacy "method" field still maps to "cargo" or "installer" for backward compatibility. Additive "install_channel", "recovery_url", and "requires_user_action" fields describe the proven owner and safe recovery state; a failed known installer route also includes "exact_installer_url". On Windows, every update payload also carries "install_origin" — one of msi-global, msi-corporate, exe-global, exe-corporate, cargo-or-installer, or unknown.

{
  "action": "update",
  "success": true,
  "current_version": "3.5.2",
  "latest_version": "3.7.2",
  "update_available": true,
  "method": "installer",
  "strategy": "msi_corporate",
  "install_origin": "msi-corporate",
  "install_channel": "msi-corporate",
  "recovery_url": "https://github.com/QubeTX/qube-network-diagnostics/releases/latest",
  "requires_user_action": false
}

The precise "strategy" values are cargo, unix_archive, mac_dmg_pkg, installer_powershell, installer_pwsh, msi_global, msi_corporate, exe_global, and exe_corporate.

Speed Test Methodology

The CLI implements SpeedQX Methodology v4, byte-identical with the website/app specification and protected by shared golden vectors:

Dense warmed latency sampling and adaptive throughput transfers.
Plateau-based warm-up removal, IQR filtering, modified trimean, and a Hodges–Lehmann stability cross-check per provider.
Circular block bootstrap with BCa 95% intervals for autocorrelated samples.
A capability-aware capacity headline plus conservative all-provider consensus, random-effects heterogeneity, HKSJ confidence intervals, and a 70% per-provider weight cap.
I² agreement bands, PDV jitter, bufferbloat deltas, approximate RPM, and honest provider availability/exclusion fields.
An anytime-valid empirical-Bernstein confidence sequence for --fast, avoiding optional-stopping bias.

For the full equations, thresholds, provider registry, and parity contract, see METHODOLOGY.md or the SpeedQX technical report.

License

PolyForm Noncommercial 1.0.0

nd300 3.7.2