chore: bump version to 0.4.0

- CMakeLists.txt VERSION 0.3.1 -> 0.4.0
- README: add Windows to platform list, update test count to 578,
  mention Windows + vcpkg in the Build section, update BUILDING.md
  table row.
- docs/REMAINING-WORK.md: refresh "Last updated" header with v0.4.0
  scope; the carrier-NAT line now correctly attributes the CGNAT
  fix to post-v0.3.1 work (HandshakeResult::server_address
  propagation).

Highlights since v0.3.1:
- Windows x86_64 (vcpkg + MSVC, separate CI workflow)
- CGNAT holepunch fix (load-bearing serverAddress propagation
  for JS server fast-mode punch trigger)
- ESP32 single-socket mode under HYPERDHT_EMBEDDED — restores
  same-LAN connectivity broken by the v0.3.0 dual-socket refactor
- Example client close path
- Misc fixes: Ctrl+C drain, NAT sampling timing, FFI for Android
  VpnService.protect()

Author: jjacke13

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.20)
 project(hyperdht-cpp
-    VERSION 0.3.1
+    VERSION 0.4.0
     LANGUAGES C CXX
     DESCRIPTION "C++ reimplementation of HyperDHT"
 )

README.md

@@ -23,24 +23,24 @@ Wire-compatible with JS `hyperdht@6.29.1`. Live-tested in both directions on the
 
 | | |
 |---|---|
-| **Tests** | 566 unit + 6 live, ASAN/UBSan clean |
+| **Tests** | 578 unit + 6 live, ASAN/UBSan clean |
 | **API parity** | Full -- wire-compatible with JS `hyperdht@6.29.1` ([audit](docs/archive/JS-PARITY-GAPS.md)) |
 | **Languages** | C++ / C / Python / Kotlin (Swift, Go, Rust planned) |
-| **Platforms** | Linux, macOS, ESP32, Android |
+| **Platforms** | Linux, macOS, Windows, Android, ESP32 |
 
 ## Build
 
 ```
 nix develop && mkdir -p build && cd build && cmake .. -G Ninja && ninja && ctest -L unit
 ```
 
-Without Nix: install `cmake`, `ninja`, `libsodium`, `libuv`, then the same cmake flow. Docker also works (`docker build -t hyperdht .`). See [BUILDING.md](docs/BUILDING.md) for full instructions (Linux, macOS, Docker, linking, troubleshooting).
+Without Nix: install `cmake`, `ninja`, `libsodium`, `libuv`, then the same cmake flow. Docker also works (`docker build -t hyperdht .`). On Windows, use vcpkg for the dependencies and MSVC — CI builds the static and shared variants on every push (`.github/workflows/windows.yml`). See [BUILDING.md](docs/BUILDING.md) for full instructions (Linux, macOS, Windows, Docker, linking, troubleshooting).
 
 ## Documentation
 
 | | |
 |---|---|
-| [Build instructions](docs/BUILDING.md) | Linux, macOS, Docker, Nix — deps, compile, link, troubleshoot |
+| [Build instructions](docs/BUILDING.md) | Linux, macOS, Windows, Docker, Nix — deps, compile, link, troubleshoot |
 | [C API reference](docs/C-API.md) | 76 functions, opaque-pointer pattern, callback-based async |
 | [C++ API reference](docs/CPP-API.md) | RAII wrappers, error codes, single-threaded event loop |
 | [Python examples](examples/python/) | Server, client, holesail tunnel, 22 wrapper tests |

docs/REMAINING-WORK.md

@@ -2,7 +2,7 @@
 
 Tasks to verify / harden the implementation, organized by category and estimated effort.
 
-**Last updated: 2026-05-02** (v0.3.1 — security audit + reusableSocket)
+**Last updated: 2026-05-08** (v0.4.0 — Windows port + CGNAT holepunch + ESP32 single-socket)
 
 ---
 
@@ -213,8 +213,10 @@ Still not exposed:
 
 - **Run a public node** — announce on the public DHT, serve real nospoon traffic
 - **Multi-region test** — clients in US, EU, Asia connecting through each other
-- **Mobile network test** — 4G/5G NAT behavior verified (v0.3.0: Android echo
-  works over carrier NAT, both ephemeral and persistent server states)
+- **Mobile network test** — 4G/5G NAT behavior verified. v0.3.0 fixed the
+  post-persistent echo bug; CGNAT holepunch landed post-v0.3.1 via
+  `HandshakeResult::server_address` propagation (relay's fresh observation
+  triggers JS server fast-mode punch — see CLAUDE.md gotcha #19).
 - **IPv6 validation** — protocol has IPv6 fields (`addresses6`); we don't exercise them
 
 ---