Migrating to Aria 3.0

Aria 3.0 raises the language baseline to C++23, rebuilds the HTTP adapter on Mira, and replaces the vendored third-party model with hash-pinned downloads. This page lists everything that can break an existing integration.

C++23 is required

Every Aria module — and therefore every consumer — now compiles as C++23. CMAKE_CXX_STANDARD defaults to 23 and the configure step rejects anything lower.

Toolchain	Minimum
GCC	14
Clang / AppleClang	19 / 21
MSVC	Visual Studio 2022 (v143)

Action: bump your project's CMAKE_CXX_STANDARD to 23 (or remove the override — Aria's default now applies).

HTTP adapter (aria::http)

native_server() is gone

The escape hatch that exposed the underlying httplib::Server& was coupled to the previous backend and is removed. Custom REST routes map to register_command():

// Before (Aria 2.x)
adapter.native_server().Get("/custom", [](const httplib::Request&,
                                          httplib::Response& res) {
    res.set_content("ok", "text/plain");
});
 
// After (Aria 3.x)
adapter.register_command("view-id", "custom-route",
    [](std::string_view args_json) {
        return std::string("ok");
    });

Behaviour notes

• The wire protocol is unchanged (REST + SSE, protocol version 2). Browsers and the bundled Web SDK need no changes.
• SSE clients no longer consume worker threads, so max_sse_clients is the single admission cap; 0 means a default of 64 instead of "bounded only by the worker count".
• Static mounts are served by the adapter: index.html default, extension based Content-Type, traversal refusal. HTTP ranges and directory listings are not supported.
• Bind addresses must be numeric; "localhost" maps to the IPv4 loopback.
• TLS still requires ARIA_HTTP_ENABLE_TLS=ON plus OpenSSL 3+ (OpenSSL 4.0 verified). tls_ca_file now enforces mandatory client verification through Mira; there is no insecure bypass.

Dependencies: pinned downloads instead of third_party

third_party/ (cpp-httplib, doctest, nlohmann_json) and the OpenSSL git submodule are removed. Dependencies default to the latest stable release on first resolution, then use the versions and SHA256 hashes recorded in dependencies.json. Explicit versions take precedence. See dependency versions for updating the lock and selecting a version. The current checked-in selection is:

Dependency	Version	Source
Mira	1.0.0	GitHub release asset
nlohmann/json	3.12.0	json.tar.xz release asset
doctest	2.5.3	raw header at locked commit
OpenSSL (TLS builds)	4.0.3	GitHub release asset

• First configure needs network access; the cache lives under build/_deps and is shared by every build flavor.
• Offline / patched builds: -DARIA_PIN_MIRA_SOURCE_DIR=/path/to/Mira (likewise ARIA_PIN_OPENSSL_SOURCE_DIR, …) uses a local tree as-is.
• CI: pre-warm the cache or accept the configure-time download; there is no submodule step anymore.
• Static aria_http additionally requires the Mira package at consumer configure time (find_package(aria) pulls it in via find_dependency(Mira)). Shared builds absorb Mira into the aria_http dylib and need nothing extra.