A finding code is the stable half of a result - what a dashboard groups by and
what someone greps a year of archived runs for. That only holds if a code means
exactly one thing forever, which fifteen ad-hoc string literals cannot promise.
By the time this was written the failure had happened twice:
- Two emitters independently produced connectivity.downstream_loss and
connectivity.loss_downstream for the same claim. Nothing objected. Anyone
aggregating either would have silently seen half their data.
- Two codes sat under nat.* while being declared Category.CONNECTIVITY.
nat.udp_unreachable is not about NAT, and the prefix decides the category,
which decides which verdict light the finding rolls up into. Renamed while
that is still cheap.
Codes are now typed FindingSpecs carrying category and default severity;
emitters reference the spec rather than retyping the string, so a typo is a
compile error and two call sites cannot disagree about a finding's category.
docs/findings-registry.md is the contract and a test reads it, failing when the
document and the code disagree on which codes exist or how severe they are.
Documentation that drifts from its implementation is worse than none, because it
still looks authoritative. The check reads table rows only, so the prose can go
on explaining which codes were retired and why.
Closes open item 1 of measurement-schema.md section 9.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Echolot
Free software for detecting and debugging local network issues from an Android phone — built for people who actually know what a neighbor table is.
Most "wifi analyzer" apps show you signal bars. Echolot aims at the layer where home and office networks actually break: duplicate DHCP servers, broken IPv6 RAs, MTU black holes, NAT64 weirdness, multicast that dies at the AP, DNS that answers differently than it should. It records what it observed, separates observation from interpretation, and exports the whole run so you can argue with it later.
Status: pre-release. The capability prober runs on real hardware; the production app and the probe server are not built yet.
Repository layout
docs/ design docs — the contract for everything below
echolot-prober/ capability prober: validates the no-root feasibility matrix on real devices
The Go probe server and the production app land here as siblings.
Design docs
The three specs are draft-complete and reviewed; treat them as the contract.
| Doc | What it defines |
|---|---|
| docs/feature-catalog-and-feasibility.md | Full feature list + the no-root feasibility matrix |
| docs/measurement-schema.md | Archived/exportable measurement JSON (observation vs finding, two-clock rule, anonymization) |
| docs/probe-protocol.md | Client↔server wire protocol (pinned TLS control plane, binary UDP data plane, STUN, canary DNS) |
| docs/build-status.md | Running log of decisions and next steps |
Privilege tiers
Every result records which tier produced it:
app— no root, no special setup. The bulk of the functionality.shizuku— ADB-shell privileges via wireless pairing, no root. Shipped in v1.root— future optional module.
Licensing
| Part | License | Why |
|---|---|---|
| All code (app, prober, server) | GPL-3.0-or-later | The value here is the platform-API research; copyleft keeps derivative apps free |
docs/ (the specs) |
CC-BY-4.0 | A wire protocol and a measurement format should be implementable by anyone, without license anxiety |
Full texts: LICENSE (GPLv3) and docs/LICENSE (CC BY 4.0).
Sources carry SPDX-License-Identifier headers.
If you want to build a compatible server or client, the protocol and schema docs are deliberately permissive — go ahead.
Building
See echolot-prober/README.md. Short version, from echolot-prober/:
echo "sdk.dir=/path/to/Android/sdk" > local.properties
./gradlew :app:assembleDebug