diff --git a/apollo-federation/src/lib.rs b/apollo-federation/src/lib.rs
index 99d340e881..6ce5b82a08 100644
--- a/apollo-federation/src/lib.rs
+++ b/apollo-federation/src/lib.rs
@@ -59,6 +59,19 @@ use crate::subgraph::ValidSubgraph;
 pub use crate::supergraph::ValidFederationSubgraph;
 pub use crate::supergraph::ValidFederationSubgraphs;
 
+/// Part of the key for distributed query plan cache.
+///
+/// Update this every time the cache key or the query plan format has to change,
+/// specifically if an old serialized query plan cannot always be deserialized and used correctly
+/// in the current Router version.
+///
+/// When changed it MUST BE CALLED OUT PROMINENTLY IN THE CHANGELOG.
+///
+/// Historically this was based in part on the federation version extracted from the build metadata
+/// in the router-bridge crate version number (e.g. `0.6.4+v2.9.3`) but any arbitrary string works.
+/// The next version can be "2", and this paragraph removed.
+pub const CACHE_KEY_VERSION: &str = "1:federation:v2.9.3";
+
 pub(crate) type SupergraphSpecs = (&'static LinkSpecDefinition, &'static JoinSpecDefinition);
 
 pub(crate) fn validate_supergraph_for_query_planning(
diff --git a/apollo-router/build/main.rs b/apollo-router/build/main.rs
index 763d894df0..b323c668bb 100644
--- a/apollo-router/build/main.rs
+++ b/apollo-router/build/main.rs
@@ -1,37 +1,5 @@
-use std::fs;
-use std::path::PathBuf;
-
 mod studio;
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
-    let cargo_manifest: serde_json::Value = basic_toml::from_str(
-        &fs::read_to_string(PathBuf::from(&env!("CARGO_MANIFEST_DIR")).join("Cargo.toml"))
-            .expect("could not read Cargo.toml"),
-    )
-    .expect("could not parse Cargo.toml");
-
-    let router_bridge = cargo_manifest
-        .get("dependencies")
-        .expect("Cargo.toml does not contain dependencies")
-        .as_object()
-        .expect("Cargo.toml dependencies key is not an object")
-        .get("router-bridge")
-        .expect("Cargo.toml dependencies does not have an entry for router-bridge");
-    let router_bridge_version = router_bridge
-        .as_str()
-        .or_else(|| {
-            router_bridge
-                .as_object()
-                .and_then(|o| o.get("version"))
-                .and_then(|version| version.as_str())
-        })
-        .expect("router-bridge does not have a version");
-
-    let mut it = router_bridge_version.split('+');
-    let _ = it.next();
-    let fed_version = it.next().expect("invalid router-bridge version format");
-
-    println!("cargo:rustc-env=FEDERATION_VERSION={fed_version}");
-
     studio::main()
 }
diff --git a/apollo-router/src/query_planner/bridge_query_planner.rs b/apollo-router/src/query_planner/bridge_query_planner.rs
index cc058b5555..bbe4314ca2 100644
--- a/apollo-router/src/query_planner/bridge_query_planner.rs
+++ b/apollo-router/src/query_planner/bridge_query_planner.rs
@@ -859,9 +859,6 @@ pub(crate) fn metric_rust_qp_init(init_error_kind: Option<&'static str>) {
 
 #[cfg(test)]
 mod tests {
-    use std::fs;
-    use std::path::PathBuf;
-
     use serde_json::json;
     use test_log::test;
     use tower::Service;
@@ -1405,28 +1402,6 @@ mod tests {
             .await
     }
 
-    #[test]
-    fn router_bridge_dependency_is_pinned() {
-        let cargo_manifest: serde_json::Value = basic_toml::from_str(
-            &fs::read_to_string(PathBuf::from(&env!("CARGO_MANIFEST_DIR")).join("Cargo.toml"))
-                .expect("could not read Cargo.toml"),
-        )
-        .expect("could not parse Cargo.toml");
-        let router_bridge_version = cargo_manifest
-            .get("dependencies")
-            .expect("Cargo.toml does not contain dependencies")
-            .as_object()
-            .expect("Cargo.toml dependencies key is not an object")
-            .get("router-bridge")
-            .expect("Cargo.toml dependencies does not have an entry for router-bridge")
-            .as_str()
-            .unwrap_or_default();
-        assert!(
-            router_bridge_version.contains('='),
-            "router-bridge in Cargo.toml is not pinned with a '=' prefix"
-        );
-    }
-
     #[tokio::test]
     async fn test_both_mode() {
         let mut harness = crate::TestHarness::builder()
diff --git a/apollo-router/src/query_planner/caching_query_planner.rs b/apollo-router/src/query_planner/caching_query_planner.rs
index 209adcc856..09837909c0 100644
--- a/apollo-router/src/query_planner/caching_query_planner.rs
+++ b/apollo-router/src/query_planner/caching_query_planner.rs
@@ -5,6 +5,9 @@ use std::sync::Arc;
 use std::task;
 
 use apollo_compiler::validation::Valid;
+/// Update this key every time the cache key or the query plan format has to change.
+/// When changed it MUST BE CALLED OUT PROMINENTLY IN THE CHANGELOG.
+use apollo_federation::CACHE_KEY_VERSION;
 use futures::future::BoxFuture;
 use indexmap::IndexMap;
 use query_planner::QueryPlannerPlugin;
@@ -632,11 +635,6 @@ pub(crate) struct CachingQueryKey {
     pub(crate) config_mode: Arc<QueryHash>,
 }
 
-// Update this key every time the cache key or the query plan format has to change.
-// When changed it MUST BE CALLED OUT PROMINENTLY IN THE CHANGELOG.
-const CACHE_KEY_VERSION: usize = 1;
-const FEDERATION_VERSION: &str = std::env!("FEDERATION_VERSION");
-
 impl std::fmt::Display for CachingQueryKey {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let mut hasher = Sha256::new();
@@ -654,8 +652,8 @@ impl std::fmt::Display for CachingQueryKey {
 
         write!(
             f,
-            "plan:cache:{}:federation:{}:{}:opname:{}:metadata:{}",
-            CACHE_KEY_VERSION, FEDERATION_VERSION, self.hash, operation, metadata,
+            "plan:cache:{}:{}:opname:{}:metadata:{}",
+            CACHE_KEY_VERSION, self.hash, operation, metadata,
         )
     }
 }