openssl-static

Seamless stdlib networking from raw threads: the real stdlib HTTP::Client, TCPSocket and OpenSSL::SSL::Socket::Client work as-is from pthreads that Crystal never started — e.g. the egui/sokol frame loop and its worker threads in Android apps. On such threads Fiber::ExecutionContext.current is nil, so every stdlib IO call dies (NilAssertionError "Thread#scheduler cannot be nil", or a segfault in the Boehm GC when stdlib tries to auto-create the missing ::Thread).

The shard patches the failure points and nothing else:

• Crystal::EventLoop.current — when the running thread has no execution context, returns a stateless blocking implementation of the same abstract interface (poll/recv/send/connect over libc): the thread simply blocks, no fibers involved. Scheduler-equipped threads keep their io_uring/epoll loop untouched. Fiber.syscall (DNS getaddrinfo offload) likewise runs inline on raw threads.
• Crystal::System::Thread.current_thread — hands a raw thread a stand-in ::Thread (pre-created at require time) instead of lazily running ::Thread.new, which dies in GC_get_my_stackbottom on a thread the GC never registered (Fiber.current reaches it from everywhere, e.g. Crystal::FdLock on every socket close). The main thread keeps the stdlib lazy create-and-store behavior.
• GC.malloc / GC.malloc_atomic / GC.realloc — a raw thread that triggers a Boehm collection aborts the process with "Collecting from unknown thread"; the hooks register the running pthread (GC_register_my_thread, true stack bounds via pthread_getattr_np) at its first allocation. Per-thread cost is one zero-initialized TLS flag read.

The result — no shim API to learn:

require "openssl-static"

# from any thread, raw or scheduled:
body = HTTP::Client.get("https://example.com")

ctx = OpenSSL::SSL::Context::Client.new
ctx.ca_certificates = "/etc/ssl/certs/ca-certificates.crt"
HTTP::Client.new("api.example.com", tls: ctx) do |client|
  client.post("/v1/thing", form: {"q" => "hi"})
end

Linking

The shard uses the stdlib OpenSSL bindings — there is no C shim to compile anymore (the old OpenSSL::HTTPS micro-client is gone). Consumers must link libssl/libcrypto:

• Desktop — the system shared libraries, nothing to configure.

• Android/iOS — a static OpenSSL build linked into the app binary together with the Crystal code, e.g. for Android:

  # link: ... -L"$OPENSSL_ANDROID/lib" -lssl -lcrypto

That static-mobile, seamless-desktop combination is what the shard name says.

Tests

crystal spec    # local TLS oracle: python3 https server on 127.0.0.1

The raw-thread spec runs a real HTTP::Client + TLS handshake (verified against a self-signed SAN IP:127.0.0.1 cert) on a genuine pthread_create thread, plus failure cases with a wrong CA.