diff --git a/Cargo.lock b/Cargo.lock
index 40df819..4e59e6a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2083,11 +2083,12 @@ dependencies = [
 
 [[package]]
 name = "card_game"
-version = "0.4.0"
-source = "git+https://git.aleshym.co/Quaternions/card_game?rev=99b49e62#99b49e629e2372962b082325503c33e20a458818"
+version = "0.4.1"
+source = "git+https://git.aleshym.co/Quaternions/card_game?rev=fb01881f#fb01881f629647eb649d044a63a145cc1da54599"
 dependencies = [
  "arrayvec 0.7.6 (sparse+https://git.aleshym.co/api/packages/Quaternions/cargo/)",
  "serde",
+ "serde_derive",
 ]
 
 [[package]]
@@ -4599,12 +4600,13 @@ dependencies = [
 
 [[package]]
 name = "klondike"
-version = "0.3.0"
-source = "git+https://git.aleshym.co/Quaternions/card_game?rev=99b49e62#99b49e629e2372962b082325503c33e20a458818"
+version = "0.4.0"
+source = "git+https://git.aleshym.co/Quaternions/card_game?rev=fb01881f#fb01881f629647eb649d044a63a145cc1da54599"
 dependencies = [
  "card_game",
  "rand 0.10.1",
  "serde",
+ "serde_derive",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index e25c800..f33d476 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -38,8 +38,8 @@ solitaire_core   = { path = "solitaire_core" }
 solitaire_sync   = { path = "solitaire_sync" }
 solitaire_data   = { path = "solitaire_data" }
 solitaire_engine = { path = "solitaire_engine" }
-klondike         = { git = "https://git.aleshym.co/Quaternions/card_game", rev = "99b49e62", features = ["serde"] }
-card_game        = { git = "https://git.aleshym.co/Quaternions/card_game", rev = "99b49e62", features = ["serde"] }
+klondike         = { git = "https://git.aleshym.co/Quaternions/card_game", rev = "fb01881f", features = ["serde"] }
+card_game        = { git = "https://git.aleshym.co/Quaternions/card_game", rev = "fb01881f", features = ["serde"] }
 
 # Bevy with `default-features = false` to avoid the unused
 # `bevy_audio → rodio + symphonia + cpal 0.15 + alsa 0.9` chain.
diff --git a/solitaire_core/src/klondike_adapter.rs b/solitaire_core/src/klondike_adapter.rs
index 3db8362..e364050 100644
--- a/solitaire_core/src/klondike_adapter.rs
+++ b/solitaire_core/src/klondike_adapter.rs
@@ -211,8 +211,9 @@ pub fn skip_cards_from_count(skip: usize) -> Option<SkipCards> {
 // ── Legacy serde mirror types (kept for backward compatibility) ───────────────
 //
 // These types were introduced when upstream `klondike` had no serde feature.
-// At rev 99b49e62, upstream provides full serde support, and `GameState`
-// serialises `saved_moves` directly as `Vec<KlondikeInstruction>` (schema v4).
+// Mainline `klondike` now provides full serde support (with a hand-written
+// compact `KlondikeInstruction` impl), and `GameState` serialises
+// `saved_moves` directly as `Vec<KlondikeInstruction>` (schema v4).
 //
 // The mirror types are retained for three reasons:
 //   1. Schema v3 migration: `AnyInstruction` in `game_state.rs` uses
diff --git a/solitaire_engine/src/feedback_anim_plugin.rs b/solitaire_engine/src/feedback_anim_plugin.rs
index a168a28..20fb5f1 100644
--- a/solitaire_engine/src/feedback_anim_plugin.rs
+++ b/solitaire_engine/src/feedback_anim_plugin.rs
@@ -199,7 +199,7 @@ fn card_to_id(card: &Card) -> u32 {
         Suit::Hearts => 2,
         Suit::Spades => 3,
     };
-    suit_index * 13 + (card.rank().value() as u32 - 1)
+    suit_index * 13 + (card.rank() as u32 - 1)
 }
 
 // ---------------------------------------------------------------------------
diff --git a/solitaire_engine/src/radial_menu.rs b/solitaire_engine/src/radial_menu.rs
index 0ba9827..131e190 100644
--- a/solitaire_engine/src/radial_menu.rs
+++ b/solitaire_engine/src/radial_menu.rs
@@ -361,7 +361,7 @@ fn pile_cards(game: &GameState, pile: &KlondikePile) -> Vec<(Card, bool)> {
 
 /// Maps a `card_game::Card` to a stable `u32` identity used by `CardEntity`
 /// and systems that still track cards by numeric ID.
-/// Encoding: `suit_index * 13 + (rank.value() - 1)`, range 0..=51.
+/// Encoding: `suit_index * 13 + (rank as u8 - 1)`, range 0..=51.
 fn card_to_id(card: &Card) -> u32 {
     use solitaire_core::card::Suit;
     let suit_index: u32 = match card.suit() {
@@ -370,7 +370,7 @@ fn card_to_id(card: &Card) -> u32 {
         Suit::Hearts => 2,
         Suit::Spades => 3,
     };
-    suit_index * 13 + (card.rank().value() as u32 - 1)
+    suit_index * 13 + (card.rank() as u32 - 1)
 }
 
 const fn foundations() -> [Foundation; 4] {
diff --git a/solitaire_engine/src/theme/mod.rs b/solitaire_engine/src/theme/mod.rs
index 877ed3b..86fde60 100644
--- a/solitaire_engine/src/theme/mod.rs
+++ b/solitaire_engine/src/theme/mod.rs
@@ -43,11 +43,11 @@ pub use registry::{
 
 /// Hashable lookup key into [`CardTheme::faces`].
 ///
-/// Distinct from `solitaire_core::Card`: the core type carries an `id`
-/// and a `face_up` flag that vary per deal, neither of which is
-/// relevant to image lookup. `CardKey` is just the (suit, rank) pair
-/// that uniquely identifies which artwork to draw.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Serialize, Deserialize)]
+/// Distinct from `card_game::Card`, which also encodes a deck id: `CardKey`
+/// is just the (suit, rank) pair that uniquely identifies which artwork to
+/// draw. Serialised theme manifests address faces by
+/// [`CardKey::manifest_name`] strings, not by serialising `CardKey` itself.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct CardKey {
     pub suit: Suit,
     pub rank: Rank,
diff --git a/solitaire_wasm/src/lib.rs b/solitaire_wasm/src/lib.rs
index 70d895b..f6a814e 100644
--- a/solitaire_wasm/src/lib.rs
+++ b/solitaire_wasm/src/lib.rs
@@ -97,7 +97,7 @@ fn card_to_id(card: &solitaire_core::card::Card) -> u32 {
         Suit::Hearts => 2,
         Suit::Spades => 3,
     };
-    suit_index * 13 + (card.rank().value() as u32 - 1)
+    suit_index * 13 + (card.rank() as u32 - 1)
 }
 
 impl From<&(solitaire_core::card::Card, bool)> for CardSnapshot {
@@ -110,7 +110,7 @@ impl From<&(solitaire_core::card::Card, bool)> for CardSnapshot {
                 Suit::Hearts => "hearts",
                 Suit::Spades => "spades",
             },
-            rank: card.rank().value(),
+            rank: card.rank() as u8,
             face_up: *face_up,
         }
     }