diff --git a/src/github/matrix.rs b/src/github/matrix.rs
index 11c2197..66929dc 100644
--- a/src/github/matrix.rs
+++ b/src/github/matrix.rs
@@ -3,7 +3,7 @@ use itertools::iproduct;
 use nix_rs::flake::system::System;
 use serde::{Deserialize, Serialize};
 
-use crate::config::Config;
+use crate::config::{Config, SubFlakish};
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct GitHubMatrixRow {
@@ -29,9 +29,25 @@ pub(crate) async fn dump_github_actions_matrix(
     cfg: &Config,
     systems: Vec<System>,
 ) -> anyhow::Result<()> {
-    // TODO: Should take into account systems whitelist
-    // Ref: https://github.com/srid/nixci/blob/efc77c8794e5972617874edd96afa8dd4f1a75b2/src/config.rs#L104-L105
-    let matrix = GitHubMatrix::new(systems, cfg.subflakes.0.keys().cloned().collect());
+    let include = iproduct!(
+        systems,
+        cfg.subflakes
+            .0
+            .iter()
+            .collect::<Vec<(&String, &SubFlakish)>>()
+    )
+    .flat_map(|(system, (k, v))| {
+        if v.can_build_on(&vec![system.clone()]) {
+            Some(GitHubMatrixRow {
+                system,
+                subflake: k.to_string(),
+            })
+        } else {
+            None
+        }
+    })
+    .collect();
+    let matrix = GitHubMatrix { include };
     println!("{}", serde_json::to_string(&matrix)?);
     Ok(())
 }