Johnathan Corgan
6a564e26ac
Everything the release needs except the version number, which stays at 0.5.0-dev until the tag. The changelog entry covers only the work that is new on this line. The point release's forty-six entries arrived under their own heading with the forward merge and are left alone; the twenty that remained are regrouped by topic and eight more added for changes no entry covered. Three of those eight matter to someone upgrading. Five root modules and four re-exports left the public library surface and Node::connections narrowed, none of it recorded anywhere; the entry names what to use instead and distinguishes the removed connection-phase enum from the Noise type of the same name, which is a different type that still exists. Tracing targets moved, so an existing RUST_LOG filter stops matching rather than erroring. And the handshake resend interval key no longer governs the first resend, which is now a constant, though it still governs later ones. Seven more entries cover the work that landed after the first content pass was written: the experimental native datagram API, the fipsctl probe diagnostic, per-instance transport addressing, the app-owned UDP socket seam, and the connect, disconnect and path-MTU fixes. The four bug fixes among them all reach the deployed line, so the release notes no longer claim this release carries exactly one fix for a shipped bug; it carries four. There is no security section, because after the split every security entry belongs to the point release. The release notes say so plainly rather than leaving a reader upgrading across both releases to conclude this one carries no security work. The notes are organized by audience, since the release spans OpenWrt routers, embedders, FreeBSD, and the existing platforms, and a single list serves none of them. The native datagram API is given a section of its own rather than folded into the embedding seam: it is a client-facing API rather than a way to host a node, and its one rule with no Berkeley-socket counterpart, that the v1 wire carries no half-close, needs to be somewhere a client author will read it. FreeBSD is advertised as supported on x86_64 only, stated wherever the platform appears. Android is advertised as an embedding seam and not as a supported platform: a compile-gated library surface with no artifact and no host application guide. The configuration table rename is carried through every shipped file that taught the old spelling: nine documentation files, the OpenWrt sample config and a test generator, twenty-two sites in all. Guides written this same cycle were among them, which is how the omission was found. The documentation that arrived with the native API was checked for the same omission and was already clean. The compatibility tests keep the old spelling deliberately, since they exist to test the fold. The changelog section is the fold of master's [Unreleased], not a snapshot of it. An earlier version of this commit took a copy that then drifted, so each section ended up holding a bullet the other did not and re-folding them would have picked a winner silently. Both causes were fixed on master instead — the NixOS module had never been recorded there, and the pre-release batch of fixes was new — so [Unreleased] is a strict superset and this is a copy rather than a merge. [0.5.0] carries all forty-six bullets byte for byte, [Unreleased] is empty, and [0.4.2] is untouched, checked by hashing it against master's copy. The BLE work landed after the content pass and gets one summary entry in the changelog and one section in the release notes rather than nine bullets: the ble_available gate replacing target_os = "linux", packet-boundary recovery for stream-oriented backends, peer recognition by node identity instead of a rotating link address, the L2CAP PSM moving into the backend seam and onto the advertisement, the embedder-supplied Android radio, bounded probe retry, and inbound handshakes moved off the accept loop. The two release-notes copies no longer share their link paths. Relative links resolve from one directory only, so the seven written for docs/releases/ all 404ed from the root copy. The root copy now uses paths from the repository root and the versioned copy keeps the ../ form; both sets were resolved against the tree. The same two links are broken the same way in the v0.4.0 through v0.4.2 notes, left as shipped history. The contributor tallies are re-derived against maint..HEAD rather than adjusted: twenty commits from outside the project and 171 from me, with Arjen at fifteen and fr34aky at two. An earlier count of twelve and 138 was carried from a measurement taken three days before this content was written, and the BLE branch widened the gap after it. Arjen's NixOS flake module, the UDP sin6_scope_id fix and most of the BLE rework were uncredited, as was fr34aky's L2CAP PSM seam. They want one last re-derive at tag time if anything lands before the tag. A sweep of all 99 tracked markdown files against the tree corrected fifty-three of them. Four told the reader to run a build.sh that does not exist; the only harness builder is testing/scripts/build.sh. The BLE build prerequisites were described as optional on the strength of a probe that build.rs does not perform, and bluez was named a build prerequisite when libdbus-sys asks only for libdbus-1-dev and pkg-config and bluez is the runtime daemon. Link cost is the primary sort key in next-hop ranking, not reserved for future use; Ethernet runs on macOS as well as Linux; the BLE MTU is the L2CAP CoC MTU rather than a negotiated ATT_MTU; effective Ethernet MTU is 1497; the LAN discovery subsystem is src/mdns and eight citations still named a src/discovery that never existed here. The connectivity states in three tutorials were invented, and their jq filters matched nothing including healthy peers. One command filtered on a literal fd97: address prefix, which only the first byte of fixes, so it returned empty for all but one reader in 256 and every later step using the variable failed silently. transports.tor.advertise_on_nostr was undocumented despite being validated against node.rendezvous.nostr.enabled. The transport design document gains the BLE section it never had, written from the source: the backend cascade and its compile_error tripwire, the platform gate, the PSM advertisement wire layout and the byte budget that forces a 16-bit service-data key, and the probe and admission bounds. Three source files carried the same class of staleness and are corrected with the documentation: the OpenWrt ipk usage line and Makefile error text both named a packaging/openwrt that does not exist, and chaos.sh parsed --subnet without listing it. Folded in with the content commit, having been prepared alongside it: The three GitHub Action pins that had gone stale. Every third-party action is pinned to a commit SHA, nothing reports that a pin has aged, and re-resolving all ten against their tags found dorny/test-reporter@v2, taiki-e/install-action@v2 and vmactions/freebsd-vm@v1 had moved. The three install-action@nextest references stay unpinned, since that action reads the tool to install from the ref name. check-action-pins.sh passes at 75 references and all nine workflow files parse. The lockfile refresh, which is the mutating half of the dependency sweep. Thirty-six packages move to their latest semver-compatible versions and every one is transitive; nothing declared in Cargo.toml changes version. No advisory forces any of them. It was taken before the validation battery, because a gate run against a lockfile that later moves proves nothing about what ships. The sha2 0.10 to 0.11, hkdf 0.12 to 0.13 and bech32 0.11 to 0.12 majors, three of the four deferred at v0.4.0 for change surface rather than security. All three land with no source change. sha2 and hkdf must move together, since both depend on digest 0.11, and neither changes an algorithm. That matters because the chaining-key KDF in the Noise handshake is built on Hkdf::<Sha256>, where an output change would be a wire break rather than a compile error; no known-answer vectors exist for that path, so the wire-compatibility gate is what covers it. secp256k1 0.31 is deliberately absent, since nostr's own requirement would leave two copies of the ECC library in the tree. The README support matrix, rebuilt as one feature table broken out by Linux variety. A single Linux column hid that Debian, Ubuntu, Arch and NixOS are one glibc build differing in packaging, that OpenWrt is musl and drops BLE, and that Android is not a daemon platform. Transport rows sort by how many platforms carry them. A Native API row reads its platform set from the cfg gates. The installer row becomes a package format row naming the artifact, and only the .deb is exercised per release. Four changelog and release-note gaps the BLE re-walk found: a Bluetooth LE bullet stranded inside the released 0.4.2 section, a missing Fixed entry for the scan and probe loop counting a pool-refused connection as an established link, the unnamed embedder call that installs an application-owned radio, and the fact that stopping the transport now stops scanning as well as advertising. Three release-document gaps found walking the unsurveyed commits: the UDP reuse-flag fix stated in the direction opposite to the one it was made, with the silent second-daemon bind it prevents left unsaid; the corrected native-API socket paragraph carried into both release-note copies, which still named SOCK_SEQPACKET on FreeBSD and two kernels where three are handled; and the coordinate-cache hardening, which shipped with no text anywhere despite adding four operator-visible status fields. That last entry states plainly that the checks are mitigations and not a closure, since the coordinate is still not authenticated. Also folded in, the documentation pass that followed the content commit: A stage-pipeline diagram for the probe, embedded in the fipsctl reference under the five-stage list. It draws the five stages left to right with each stage's failure reasons below it, and the bypass that skips both lookup stages when the coordinates are cached or the target is a direct peer. Its branches come from the probe state machine rather than from the report, so the path stage is drawn as the one failure that does not stop the probe. A rewrite of the README's "What FIPS does" section. It now opens with what a machine running FIPS gets, rather than with the two deployment modes, and gives the self-organizing and permissionless property its own paragraph since it holds for both modes. A regrouping of the README's feature list into the mesh, getting traffic onto it, and running a node, with a bullet added for the native datagram API, which had none despite sitting in the support matrix. The Quick start now leads with the released packages rather than a source build. It also fixes a real defect: the package enables fips.service and fips-dns.service and starts neither on a fresh install, so .fips name resolution was silently dead until the next reboot and neither page said to start the service. A rewrite of the release notes. They opened with seven subsections of upgrade caveats and reached the first feature two hundred lines in; they now open with a summary of the release and elaborate below it in the same order. Android is stated as supported through an embedded crate rather than as a standalone daemon, consistently across all three documents. The OpenWrt pair is corrected: it is 802.11s between routers with FIPS supplying encryption, authentication and routing, plus a convention of an open !FIPS SSID a client joins over WiFi, not meshing over a router's own radios. The probe's path output is described as the least-common-ancestor walk, which is the worst-case fallback route rather than the route a packet takes. Detail that did not change what a reader does was cut from the notes and kept in the changelog.
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FIPS Concepts
A novice-friendly introduction to what FIPS is, why it exists, and the mental model behind a self-organizing mesh. For the protocol stack, identity system, and encryption walkthrough, see fips-architecture.md. For prior art and academic citations, see fips-prior-work.md.
What is FIPS?
FIPS is a self-organizing mesh network that can operate natively over a variety of physical and logical media, such as local area networks, Bluetooth, or the existing internet as an overlay; radio and serial links are in the planned set. The long-term goal is infrastructure that can function alongside or ultimately replace dependence on the Internet itself. Systems running FIPS establish peer connections, authenticate each other, and route traffic for each other without any central authority or global topology knowledge, and allow end-to-end encrypted sessions between any two nodes regardless of how many hops separate them.
Nodes in the mesh route traffic for each other using Nostr identities (npubs) as network addresses. Applications can access the mesh through a native FIPS datagram service, or through an IPv6 adaptation layer that presents each node as an IPv6 endpoint for compatibility with existing IP-based applications.
Both columns are the same mesh. On the left an unmodified program keeps
the stack it already has, and reaches the mesh through fips0, a
virtual network interface that carries its IPv6 packets. On the right a
FIPS-aware program names the far node by its key and skips the IP layers
altogether. The two protocols in the middle are the mesh's own: FSP
encrypts end to end between the two nodes, and FMP authenticates
each hop and decides where a packet goes next.
fips-architecture.md takes them in order.
Why FIPS?
Self-sovereign identity: FIPS nodes generate their own addresses, node IDs, and security credentials without coordination with any central authority. These identities can be long-term fixed or may be ephemeral, changed at any time. These identities are not visible to the FIPS network itself — they are used only at the application layer and for end-to-end session encryption.
Infrastructure independence: The internet depends on centralized infrastructure — ISPs, backbone providers, DNS, certificate authorities. FIPS works over any transport that can carry packets: a serial connection, onion-routed connections through Tor, local area networking, radio links between remote sites, or the existing internet as an overlay. When the internet is unavailable, unreliable, or untrusted, the mesh still works.
Privacy by design: FIPS provides secure, authenticated, and encrypted communication between any two nodes in the mesh, independent of the mix of transports used along the routed path between them. Furthermore, the mesh itself is designed to minimize metadata exposure — intermediate nodes route packets without learning the identities of the endpoints.
Zero configuration: Nodes discover each other and build routing automatically. Connect to one peer and you can reach the entire mesh. The network self-heals around failures and adapts to changing topology.
A Self-Organizing Mesh
Traditional networks are built top-down. A central authority assigns addresses, configures routing tables, provisions hardware, and manages the topology. If the authority disappears or the infrastructure fails, the network fails with it. Nodes cannot reach each other without infrastructure mediating the connection.
FIPS inverts this model. There is no central authority, no address assignment service, no routing table pushed from above. Each node generates its own identity from a cryptographic keypair. Each node independently decides which peers to connect to and which transports to use. From these local decisions alone, the network self-organizes:
- A spanning tree forms through distributed parent selection, giving every node a coordinate in the network without any node knowing the full topology
- Bloom filters propagate through gossip, so each node learns which peers can reach which destinations — again without global knowledge
- Routing decisions are made locally at each hop, using only the node's immediate peers and cached coordinate information
Each peer link and end-to-end session actively measures RTT, loss, jitter, and goodput through a lightweight in-band Metrics Measurement Protocol (MMP), providing operator visibility and a foundation for quality-aware routing.
The result is a network that builds itself from the bottom up, heals around failures automatically, and scales without central coordination. Adding a node is as simple as connecting to one existing peer — the network integrates the new node through its normal mesh protocols.
Specific Design Goals
- Nostr-native identity and cryptography — Use Nostr keypairs as node identities and leverage secp256k1, Schnorr signatures, and SHA-256
- Transport agnostic — Support overlay, shared medium, and point-to-point transports transparently
- Self-organizing — Automatic topology discovery and route optimization
- Privacy preserving — Minimize metadata leakage across untrusted links
- Resilient — Self-healing with graceful degradation
Non-goals include:
- Reliable delivery — FIPS provides a best-effort datagram service; retransmission and ordering are left to applications or higher-layer protocols
- Anonymity — Direct peers learn each other's identity; FIPS minimizes metadata exposure but is not an anonymity network like Tor
- Congestion control — FIPS measures link quality but does not implement flow control or congestion avoidance at the mesh layer
Where to Read Next
- fips-architecture.md — protocol stack, identity system, two-layer encryption, MTU as a cross-cutting concern
- fips-spanning-tree.md — how the tree forms and reconverges
- fips-bloom-filters.md — how reachability information propagates
- fips-mesh-operation.md — how the pieces work together at runtime
- fips-prior-work.md — designs and protocols FIPS builds on