diff --git a/satrs-core/Cargo.toml b/satrs-core/Cargo.toml
index 19948e4..0c6c2eb 100644
--- a/satrs-core/Cargo.toml
+++ b/satrs-core/Cargo.toml
@@ -8,11 +8,14 @@ edition = "2021"
 [dependencies]
 delegate = "0.8"
 hashbrown = "0.13"
-heapless = "0.7"
 paste = "1.0"
 dyn-clone = "1.0"
 embed-doc-image = "0.1"
 
+[dependencies.heapless]
+version = "0.7"
+optional = true
+
 [dependencies.num-traits]
 version = "0.2"
 default-features = false
@@ -54,7 +57,7 @@ std = ["downcast-rs/std", "alloc", "bus", "postcard/use-std", "crossbeam-channel
 alloc = ["serde/alloc", "spacepackets/alloc"]
 serde = ["dep:serde", "spacepackets/serde"]
 crossbeam = ["crossbeam-channel"]
-heapless = []
+heapless = ["dep:heapless"]
 doc-images = []
 
 [package.metadata.docs.rs]