diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Revision history for typelet
 
+## 0.1.6 -- 2025-07-19
+
+* Relax bounds [together with Gabriele Sales]
+* Use ghc-tcplugin-api 0.16
+
 ## 0.1.5 -- 2025-03-11
 
 * Use ghc-tcplugin-api 0.14 [Chan Siu Man]
diff --git a/src/TypeLet/Plugin/Constraints.hs b/src/TypeLet/Plugin/Constraints.hs
--- a/src/TypeLet/Plugin/Constraints.hs
+++ b/src/TypeLet/Plugin/Constraints.hs
@@ -147,7 +147,7 @@
 -- stuff out of scope...? (the whole "coercions cannot simply be zapped" thing)
 -- See also https://gitlab.haskell.org/ghc/ghc/-/issues/8095#note_108189 .
 evidenceEqual :: ResolvedNames -> CEqual -> EvTerm
-evidenceEqual ResolvedNames{..} (CEqual k a b) =
+evidenceEqual ResolvedNames{..} (CEqual k a b) = EvExpr $
     evDataConApp
       (classDataCon clsEqual)
       [k, a, b]
diff --git a/src/TypeLet/UserAPI.hs b/src/TypeLet/UserAPI.hs
--- a/src/TypeLet/UserAPI.hs
+++ b/src/TypeLet/UserAPI.hs
@@ -1,5 +1,7 @@
 {-# LANGUAGE TypeApplications #-}
 
+{-# OPTIONS_GHC -Wno-redundant-constraints #-}
+
 module TypeLet.UserAPI (
     -- * Main classes
     Let
diff --git a/test/Test/Sanity.hs b/test/Test/Sanity.hs
--- a/test/Test/Sanity.hs
+++ b/test/Test/Sanity.hs
@@ -31,7 +31,7 @@
         ]
     ]
 
-castIsId :: (Eq a, Show a, Arbitrary a) => (a -> a) -> a -> Property
+castIsId :: (Eq a, Show a) => (a -> a) -> a -> Property
 castIsId f x = x === f x
 
 testHList :: HList '[A, B, C] -> Assertion
diff --git a/typelet.cabal b/typelet.cabal
--- a/typelet.cabal
+++ b/typelet.cabal
@@ -1,7 +1,7 @@
 cabal-version:      2.4
 build-type:         Simple
 name:               typelet
-version:            0.1.5
+version:            0.1.6
 synopsis:           Plugin to faciliate type-level let
 description:        For a certain class of programs, type-level let is essential
                     in order to be able to write these programs in such a way
@@ -20,8 +20,10 @@
 tested-with:        GHC ==8.10.7
                     GHC ==9.2.8
                     GHC ==9.4.8
-                    GHC ==9.6.6
-                    GHC ==9.8.2
+                    GHC ==9.6.7
+                    GHC ==9.8.4
+                    GHC ==9.10.2
+                    GHC ==9.12.2
 
 source-repository head
   type:     git
@@ -38,10 +40,10 @@
         TypeLet.Plugin.NameResolution
         TypeLet.Plugin.Substitution
     build-depends:
-      , base             >= 4.14 && < 4.20
-      , containers       >= 0.6  && < 0.7
-      , ghc              >= 8.10 && < 9.9
-      , ghc-tcplugin-api >= 0.14 && < 0.15
+      , base             >= 4.14   && < 4.22
+      , containers       >= 0.6    && < 0.9
+      , ghc              >= 8.10   && < 9.13
+      , ghc-tcplugin-api >= 0.16.1 && < 0.17
     hs-source-dirs:
         src
     default-language:
@@ -63,6 +65,8 @@
         CPP
     ghc-options:
         -Wall
+        -Wunused-packages
+        -Wredundant-constraints
 
 test-suite test-typelet
     default-language:
@@ -100,3 +104,5 @@
       , tasty-quickcheck
     ghc-options:
         -Wall
+        -Wunused-packages
+        -Wredundant-constraints