diff --git a/CHANGELOG.md b/CHANGELOG.md
index 66af655..577e445 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ Breaking changes:
 
 New features:
 - Add `ifolded` and `imapped` (#146 by @twhitehead)
+- Add `at`/`index` instances for `purescript-unordered-collections` (HashSet & HashMap)
 
 Bugfixes:
 
diff --git a/packages.dhall b/packages.dhall
index 188382b..508f7dc 100644
--- a/packages.dhall
+++ b/packages.dhall
@@ -1,4 +1,5 @@
 let upstream =
       https://raw.githubusercontent.com/purescript/package-sets/psc-0.15.15-20240829/src/packages.dhall
+        sha256:5bab5469c75bd8c7bac517385e6dd66cca0b2651676b4a99b357753c80bbe673
 
 in  upstream
diff --git a/spago.dhall b/spago.dhall
index 4f60f2a..a96d64c 100644
--- a/spago.dhall
+++ b/spago.dhall
@@ -24,6 +24,7 @@
   , "safe-coerce"
   , "transformers"
   , "tuples"
+  , "unordered-collections"
   ]
 , packages = ./packages.dhall
 , sources = [ "src/**/*.purs", "test/**/*.purs" ]
diff --git a/src/Data/Lens/At.purs b/src/Data/Lens/At.purs
index 9149367..cc26593 100644
--- a/src/Data/Lens/At.purs
+++ b/src/Data/Lens/At.purs
@@ -6,13 +6,16 @@ module Data.Lens.At
 
 import Prelude
 
+import Data.Hashable (class Hashable)
 import Data.Identity (Identity(..))
 import Data.Lens (Lens', lens, set)
 import Data.Lens.Index (class Index)
 import Data.Map as M
+import Data.HashMap as HM
 import Data.Maybe (Maybe(..), maybe, maybe')
 import Data.Newtype (unwrap)
 import Data.Set as S
+import Data.HashSet as HS
 import Foreign.Object as FO
 
 -- | `At` is a type class whose instances let you add
@@ -50,11 +53,25 @@ instance atSet :: Ord v => At (S.Set v) v Unit where
     update Nothing = S.delete x
     update (Just _) = S.insert x
 
+instance atHashSet :: Hashable v => At (HS.HashSet v) v Unit where
+  at x = lens get (flip update)
+    where
+    get xs =
+      if HS.member x xs then Just unit
+      else Nothing
+    update Nothing = HS.delete x
+    update (Just _) = HS.insert x
+
 instance atMap :: Ord k => At (M.Map k v) k v where
   at k =
     lens (M.lookup k) \m ->
       maybe' (\_ -> M.delete k m) \v -> M.insert k v m
 
+instance atHashMap :: Hashable k => At (HM.HashMap k v) k v where
+  at k =
+    lens (HM.lookup k) \m ->
+      maybe' (\_ -> HM.delete k m) \v -> HM.insert k v m
+
 instance atForeignObject :: At (FO.Object v) String v where
   at k =
     lens (FO.lookup k) \m ->
diff --git a/src/Data/Lens/Index.purs b/src/Data/Lens/Index.purs
index 2d9d7ef..b98353c 100644
--- a/src/Data/Lens/Index.purs
+++ b/src/Data/Lens/Index.purs
@@ -5,6 +5,7 @@ module Data.Lens.Index
 
 import Prelude
 
+import Data.Hashable (class Hashable)
 import Data.Array as A
 import Data.Array.NonEmpty as NEA
 import Data.Either (Either(..))
@@ -14,8 +15,10 @@ import Data.Lens.AffineTraversal (AffineTraversal', affineTraversal)
 import Data.Lens.Iso.Newtype (_Newtype)
 import Data.List as L
 import Data.Map as M
+import Data.HashMap as HM
 import Data.Maybe (Maybe(..), fromMaybe, maybe)
 import Data.Set as S
+import Data.HashSet as HS
 import Foreign.Object as FO
 
 -- | `Index` is a type class whose instances are optics used when:
@@ -95,6 +98,15 @@ instance indexSet :: Ord a => Index (S.Set a) a Unit where
     pre :: S.Set a -> Either (S.Set a) Unit
     pre xs = if S.member x xs then Right unit else Left xs
 
+instance indexHashSet :: Hashable a => Index (HS.HashSet a) a Unit where
+  ix x = affineTraversal set pre
+    where
+    set :: HS.HashSet a -> Unit -> HS.HashSet a
+    set xs _ = xs
+
+    pre :: HS.HashSet a -> Either (HS.HashSet a) Unit
+    pre xs = if HS.member x xs then Right unit else Left xs
+
 instance indexMap :: Ord k => Index (M.Map k v) k v where
   ix k = affineTraversal set pre
     where
@@ -104,6 +116,15 @@ instance indexMap :: Ord k => Index (M.Map k v) k v where
     pre :: M.Map k v -> Either (M.Map k v) v
     pre s = maybe (Left s) Right $ M.lookup k s
 
+instance indexHashMap :: Hashable k => Index (HM.HashMap k v) k v where
+  ix k = affineTraversal set pre
+    where
+    set :: HM.HashMap k v -> v -> HM.HashMap k v
+    set s b = HM.update (\_ -> Just b) k s
+
+    pre :: HM.HashMap k v -> Either (HM.HashMap k v) v
+    pre s = maybe (Left s) Right $ HM.lookup k s
+
 instance indexForeignObject :: Index (FO.Object v) String v where
   ix k = affineTraversal set pre
     where