From OpenBSD:

https://cvsweb.openbsd.org/cgi-bin/cvsweb/ports/lang/ruby/3.0/patches/patch-ext_openssl_ossl_ocsp_c

Fix build with opaque OCSP_BASICRESP in LibreSSL 3.5.
The bug this works around should be fixed since LibreSSL 2.4.2
as far as I can tell.

Index: ext/openssl/ossl_ocsp.c
--- a/ext/openssl/ossl_ocsp.c.orig
+++ b/ext/openssl/ossl_ocsp.c
@@ -1093,7 +1093,7 @@ ossl_ocspbres_verify(int argc, VALUE *argv, VALUE self
      * exists in LibreSSL 2.1.10, 2.2.9, 2.3.6, 2.4.1.
      */
     if (!(flg & (OCSP_NOCHAIN | OCSP_NOVERIFY)) &&
-	sk_X509_num(x509s) && sk_X509_num(bs->certs)) {
+	sk_X509_num(x509s) && sk_X509_num(OCSP_resp_get0_certs(bs))) {
 	int i;
 
 	bs = ASN1_item_dup(ASN1_ITEM_rptr(OCSP_BASICRESP), bs);
From OpenBSD:

https://cvsweb.openbsd.org/cgi-bin/cvsweb/ports/lang/ruby/3.0/patches/patch-ext_openssl_extconf_rb

Make sure the TS_VERIFY_CTS_set_certs() macro gets picked up correctly.
It is a function in OpenSSL 1.1 and a macro in LibreSSL and OpenSSL 3.

Index: ext/openssl/extconf.rb
--- a/ext/openssl/extconf.rb.orig
+++ b/ext/openssl/extconf.rb
@@ -176,7 +176,7 @@ have_func("SSL_SESSION_get_protocol_version")
 have_func("TS_STATUS_INFO_get0_status")
 have_func("TS_STATUS_INFO_get0_text")
 have_func("TS_STATUS_INFO_get0_failure_info")
-have_func("TS_VERIFY_CTS_set_certs")
+have_func("TS_VERIFY_CTS_set_certs(NULL, NULL)", "openssl/ts.h")
 have_func("TS_VERIFY_CTX_set_store")
 have_func("TS_VERIFY_CTX_add_flags")
 have_func("TS_RESP_CTX_set_time_cb")
From OpenBSD:

https://github.com/openbsd/ports/commit/42d3003b55a9ace1f489aa93297aafaf7d03e8c4#diff-8c76a3fac72e780ffe364114da7bc68a1e78cb6b825d51795ca5e02bdde95cc8

LibreSSL 3.8 dropped support for EC_GFp_nist_method()

Index: ext/openssl/ossl_pkey_ec.c
--- a/ext/openssl/ossl_pkey_ec.c.orig
+++ b/ext/openssl/ossl_pkey_ec.c
@@ -743,7 +743,7 @@ static VALUE ossl_ec_group_initialize(int argc, VALUE 
             } else if (id == s_GFp_mont) {
                 method = EC_GFp_mont_method();
             } else if (id == s_GFp_nist) {
-                method = EC_GFp_nist_method();
+                method = NULL;
 #if !defined(OPENSSL_NO_EC2M)
             } else if (id == s_GF2m_simple) {
                 method = EC_GF2m_simple_method();