diff --git a/Cargo.toml b/Cargo.toml
index 8fd3835e..ab7df09f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -8,7 +8,7 @@ members = [
 resolver = "2"
 
 [workspace.package]
-version = "4.19.0"
+version = "5.0.0"
 repository = "https://github.com/cloudflare/boring"
 edition = "2021"
 
@@ -19,9 +19,9 @@ tag-prefix = ""
 publish = false
 
 [workspace.dependencies]
-boring-sys = { version = "4.19.0", path = "./boring-sys" }
-boring = { version = "4.19.0", path = "./boring" }
-tokio-boring = { version = "4.19.0", path = "./tokio-boring" }
+boring-sys = { version = "5.0.0", path = "./boring-sys" }
+boring = { version = "5.0.0", path = "./boring" }
+tokio-boring = { version = "5.0.0", path = "./tokio-boring" }
 
 bindgen = { version = "0.72.0", default-features = false, features = ["runtime"] }
 bitflags = "2.9"
diff --git a/boring-sys/Cargo.toml b/boring-sys/Cargo.toml
index ce49709d..fc74ec4b 100644
--- a/boring-sys/Cargo.toml
+++ b/boring-sys/Cargo.toml
@@ -64,6 +64,15 @@ rpk = []
 # `BORING_BSSL{,_FIPS}_SOURCE_PATH`.
 underscore-wildcards = []
 
+# UNSUPPORTED. Do not use. Fails the build.
+fips-link-precompiled = []
+
+# UNSUPPORTED. Do not use. Fails the build.
+fips-precompiled = []
+
+# UNSUPPORTED. Do not use. Fails the build.
+pq-experimental = []
+
 [build-dependencies]
 bindgen = { workspace = true }
 cmake = { workspace = true }
diff --git a/boring-sys/build/main.rs b/boring-sys/build/main.rs
index 41789cee..f1b43c0c 100644
--- a/boring-sys/build/main.rs
+++ b/boring-sys/build/main.rs
@@ -723,3 +723,12 @@ fn ensure_err_lib_enum_is_named(source_code: &mut Vec<u8>) {
             .as_bytes(),
     );
 }
+
+#[cfg(feature = "pq-experimental")]
+compile_error!("boring-sys v5 has removed the `pq-experimental` Cargo feature. Unset it.");
+
+#[cfg(feature = "fips-precompiled")]
+compile_error!("boring-sys v5 has removed the `fips-precompiled` Cargo feature. Unset it, and use the `fips` feature instead.");
+
+#[cfg(feature = "fips-link-precompiled")]
+compile_error!("boring-sys v5 has removed the `fips-link-precompiled` Cargo feature. Unset it, and use the `fips` feature instead.");