diff --git a/src/Demo/Lib.hs b/src/Demo/Lib.hs
index a4420e9..d08929b 100644
--- a/src/Demo/Lib.hs
+++ b/src/Demo/Lib.hs
@@ -16,7 +16,7 @@ elts (x:xs) = singleton x `union` elts xs
 
 {-@ rev :: xs:_ -> {v:_ | elts v == elts xs} @-}
 rev :: [a] -> [a]
-rev = go [] 
+rev = go []
   where
     {-@ go :: acc:_ -> xs:_ -> {v:_ | elts v == union (elts acc) (elts xs)} @-}
     go acc []     = acc
diff --git a/stack.yaml b/stack.yaml
index 597751b..986a4b3 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -1,20 +1,23 @@
-resolver: lts-20.1
+# resolver: lts-20.1
+resolver: nightly-2024-01-26
+
 packages:
   - .
 extra-deps:
-  - hashable-1.3.5.0
-  - rest-rewrite-0.4.1
-  - smtlib-backends-0.3
-  - smtlib-backends-process-0.3
+  - store-0.7.18@sha256:af32079e0d31413b97a1759f8ad8555507857cd4ac4015e195fb5b0a27a3ce9f,8159
+  - store-core-0.4.4.7@sha256:a2ea427ff0dde30252474dcb0641cb6928cb8a93cd5ee27d4c22adba8e729683,1489
+  - rest-rewrite-0.4.3
+  - smtlib-backends-0.3@rev:2
+  - smtlib-backends-process-0.3@rev:2
   - git: https://github.com/ucsd-progsys/liquidhaskell
-    commit: fc4a89b91fad8b7a02b72901381d4358a470e230
+    commit: 4b20537529b2143cab0214564422c94fb93df9d9
     subdirs:
       - .
       - liquidhaskell-boot
       - liquid-prelude
       - liquid-vector
   - git: https://github.com/ucsd-progsys/liquid-fixpoint
-    commit: eb339f9abdf073f8d9f0c446c309006fdf49ed42
+    commit: 5b39f1a3c49190f9e438f9cdefd7d2635c5bf7f2
 
 nix:
   packages: [cacert, git, hostname, z3]
diff --git a/stack.yaml.lock b/stack.yaml.lock
index 9aa3590..b176c39 100644
--- a/stack.yaml.lock
+++ b/stack.yaml.lock
@@ -5,95 +5,106 @@
 
 packages:
 - completed:
-    subdir: .
-    name: liquidhaskell
-    version: 0.8.10.7.1
-    git: https://github.com/ucsd-progsys/liquidhaskell
+    hackage: store-0.7.18@sha256:af32079e0d31413b97a1759f8ad8555507857cd4ac4015e195fb5b0a27a3ce9f,8159
     pantry-tree:
-      size: 327940
-      sha256: f4ed5616abda8f6d2367efa18841907cf0ac0ac55a78a811918f7286a0de3c14
-    commit: a4f2198f894810a729feb0f8d06301790ee8d1fb
+      sha256: 6e9fb2c1c59a9f2fb62abd0016841417b57b9a3e045088d48d65cc740cb1eeb9
+      size: 1292
   original:
-    subdir: .
-    git: https://github.com/ucsd-progsys/liquidhaskell
-    commit: a4f2198f894810a729feb0f8d06301790ee8d1fb
+    hackage: store-0.7.18@sha256:af32079e0d31413b97a1759f8ad8555507857cd4ac4015e195fb5b0a27a3ce9f,8159
+- completed:
+    hackage: store-core-0.4.4.7@sha256:a2ea427ff0dde30252474dcb0641cb6928cb8a93cd5ee27d4c22adba8e729683,1489
+    pantry-tree:
+      sha256: 67828df739695d14f81cd572a3085c76f65ac75f8417095afef8dfb2815f523e
+      size: 271
+  original:
+    hackage: store-core-0.4.4.7@sha256:a2ea427ff0dde30252474dcb0641cb6928cb8a93cd5ee27d4c22adba8e729683,1489
 - completed:
-    subdir: liquid-base
-    name: liquid-base
-    version: 4.14.3.0
+    hackage: rest-rewrite-0.4.3@sha256:915fb98b8c0a0f518c1a4b75bcf3ae27a3ebd5b10d60cc16a216c2fca2148ab0,3929
+    pantry-tree:
+      sha256: 4de44fbeb7bd655caeafe605406c0bc5fe1788d9cf37cdac2f18b018ee4cf5e6
+      size: 4075
+  original:
+    hackage: rest-rewrite-0.4.3
+- completed:
+    hackage: smtlib-backends-0.3@sha256:a947aead99f6a314833bddca9b502d5faea8d3bd2fc76ffb53c34d5c5b7557bc,1211
+    pantry-tree:
+      sha256: 97b88a647ac996808a93b2eab62e9e8574d9b9a451ee37a9103e209b63be012d
+      size: 275
+  original:
+    hackage: smtlib-backends-0.3@rev:2
+- completed:
+    hackage: smtlib-backends-process-0.3@sha256:caf131d3d6f6825e3a3182713130a8e14d0bd6530eeda643e8a511b546ff1a26,1676
+    pantry-tree:
+      sha256: 7147fef29b4270275168a285fc0c68784329d1276ab9e44e9a45f8d79b526220
+      size: 461
+  original:
+    hackage: smtlib-backends-process-0.3@rev:2
+- completed:
+    commit: 4b20537529b2143cab0214564422c94fb93df9d9
     git: https://github.com/ucsd-progsys/liquidhaskell
+    name: liquidhaskell
     pantry-tree:
-      size: 15057
-      sha256: ec6292884597585ab0a007b242bf5c711466a9b91fd5f3b2fbcac3602594f140
-    commit: a4f2198f894810a729feb0f8d06301790ee8d1fb
+      sha256: 9211c87ebc9f044a017c7ea04b81f391fed0d5ac02813c226a2540b5ed5086cb
+      size: 326126
+    subdir: .
+    version: 0.9.8.1
   original:
-    subdir: liquid-base
+    commit: 4b20537529b2143cab0214564422c94fb93df9d9
     git: https://github.com/ucsd-progsys/liquidhaskell
-    commit: a4f2198f894810a729feb0f8d06301790ee8d1fb
+    subdir: .
 - completed:
-    subdir: liquid-prelude
-    name: liquid-prelude
-    version: 0.8.10.2
+    commit: 4b20537529b2143cab0214564422c94fb93df9d9
     git: https://github.com/ucsd-progsys/liquidhaskell
+    name: liquidhaskell-boot
     pantry-tree:
-      size: 1029
-      sha256: c7f41d6fe87cb7d02944834ff59c5d3c7f29b1bd0c83dec5095fed21362c2546
-    commit: a4f2198f894810a729feb0f8d06301790ee8d1fb
+      sha256: f187ea8674d6e8ccdfcc49500b0dac0a9ad87b952bb0f567c842557787cd9da3
+      size: 8175
+    subdir: liquidhaskell-boot
+    version: 0.9.8.1
   original:
-    subdir: liquid-prelude
+    commit: 4b20537529b2143cab0214564422c94fb93df9d9
     git: https://github.com/ucsd-progsys/liquidhaskell
-    commit: a4f2198f894810a729feb0f8d06301790ee8d1fb
+    subdir: liquidhaskell-boot
 - completed:
-    subdir: liquid-ghc-prim
-    name: liquid-ghc-prim
-    version: 0.6.1
+    commit: 4b20537529b2143cab0214564422c94fb93df9d9
     git: https://github.com/ucsd-progsys/liquidhaskell
+    name: liquid-prelude
     pantry-tree:
-      size: 912
-      sha256: a1b1fbc8fda0d355f390bfe8ec3036e935b9d4c244217cce6e24363472cd66bd
-    commit: a4f2198f894810a729feb0f8d06301790ee8d1fb
+      sha256: e0b5d3b89feec11451cc17f17fb4712e7eff48ca200f1ce6ea1aba45c0aa8f98
+      size: 882
+    subdir: liquid-prelude
+    version: 0.9.2.8
   original:
-    subdir: liquid-ghc-prim
+    commit: 4b20537529b2143cab0214564422c94fb93df9d9
     git: https://github.com/ucsd-progsys/liquidhaskell
-    commit: a4f2198f894810a729feb0f8d06301790ee8d1fb
+    subdir: liquid-prelude
 - completed:
-    subdir: liquid-containers
-    name: liquid-containers
-    version: 0.6.2.1
+    commit: 4b20537529b2143cab0214564422c94fb93df9d9
     git: https://github.com/ucsd-progsys/liquidhaskell
+    name: liquid-vector
     pantry-tree:
-      size: 2143
-      sha256: 64ab781aea3b709196876c58ec418a1e8ef93418c71ba7f373658641beabdc7b
-    commit: a4f2198f894810a729feb0f8d06301790ee8d1fb
+      sha256: bafea6cf606205b60695b6cdfa6b64c60c7cc8f9054b7fa5ed460d4c633ac39c
+      size: 231
+    subdir: liquid-vector
+    version: 0.13.1.0
   original:
-    subdir: liquid-containers
+    commit: 4b20537529b2143cab0214564422c94fb93df9d9
     git: https://github.com/ucsd-progsys/liquidhaskell
-    commit: a4f2198f894810a729feb0f8d06301790ee8d1fb
+    subdir: liquid-vector
 - completed:
-    name: liquid-fixpoint
-    version: 0.8.10.7.1
+    commit: 5b39f1a3c49190f9e438f9cdefd7d2635c5bf7f2
     git: https://github.com/ucsd-progsys/liquid-fixpoint
+    name: liquid-fixpoint
     pantry-tree:
-      size: 22311
-      sha256: 08c682e475986bae0560d92c115eff6561aea261be0a358a1aab72aa221aa4f4
-    commit: 08fa6b6e0001c2da6b96a135523ca56107a3c0d6
+      sha256: f703433c37df88b1c1264cc3d5ff33f7cd1ee98a2b4381870ab8b3690be9eef8
+      size: 23600
+    version: 0.9.6.3
   original:
+    commit: 5b39f1a3c49190f9e438f9cdefd7d2635c5bf7f2
     git: https://github.com/ucsd-progsys/liquid-fixpoint
-    commit: 08fa6b6e0001c2da6b96a135523ca56107a3c0d6
-- completed:
-    name: rest-rewrite
-    version: 0.2.0
-    git: https://github.com/facundominguez/rest
-    pantry-tree:
-      size: 4013
-      sha256: 2a91674ccab6b0bd43dcc41fa5e2cb60cbfd35ad585df8293c2884466091d0c0
-    commit: 31e974979c90e910efe5199ee0d3721b791667f6
-  original:
-    git: https://github.com/facundominguez/rest
-    commit: 31e974979c90e910efe5199ee0d3721b791667f6
 snapshots:
 - completed:
-    size: 590102
-    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/18/27.yaml
-    sha256: 79a786674930a89301b0e908fad2822a48882f3d01486117693c377b8edffdbe
-  original: lts-18.27
+    sha256: 876a5c75d90718add42e1ad36d66000bf35050ce1c66748119897a32df613186
+    size: 563963
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/nightly/2024/1/26.yaml
+  original: nightly-2024-01-26