diff --git a/stack8.10.yaml b/stack8.10.yaml
index 8c512d8ff..822cace0a 100644
--- a/stack8.10.yaml
+++ b/stack8.10.yaml
@@ -51,10 +51,6 @@ nix:
   pure: false
   packages: [perl gmp ncurses zlib]
 
-flags:
-  encoding:
-    systemEncoding: false # See https://github.com/dmwit/encoding/issues/26
-
 # ghc-options:
 #   "$locals": -fplugin Debug.Breakpoint
 
diff --git a/stack9.0.yaml b/stack9.0.yaml
index 69352dd8f..b5cf8b40b 100644
--- a/stack9.0.yaml
+++ b/stack9.0.yaml
@@ -40,10 +40,6 @@ nix:
   pure: false
   packages: [perl gmp ncurses zlib]
 
-flags:
-  encoding:
-    systemEncoding: false # See https://github.com/dmwit/encoding/issues/26
-
 # ghc-options:
 #   "$locals": -fplugin Debug.Breakpoint
 
diff --git a/stack9.12.yaml b/stack9.12.yaml
index 4cdecdbf2..509bd5fb6 100644
--- a/stack9.12.yaml
+++ b/stack9.12.yaml
@@ -41,10 +41,6 @@ nix:
   pure: false
   packages: [perl gmp ncurses zlib]
 
-flags:
-  encoding:
-    systemEncoding: false # See https://github.com/dmwit/encoding/issues/26
-
 # ghc-options:
 #   "$locals": -Wno-x-partial
 #   "$locals": -fplugin Debug.Breakpoint
diff --git a/stack9.2.yaml b/stack9.2.yaml
index 322b1f6d3..70cee3351 100644
--- a/stack9.2.yaml
+++ b/stack9.2.yaml
@@ -30,10 +30,6 @@ nix:
   pure: false
   packages: [perl gmp ncurses zlib]
 
-flags:
-  encoding:
-    systemEncoding: false # See https://github.com/dmwit/encoding/issues/26
-
 # ghc-options:
 #   "$locals": -fplugin Debug.Breakpoint
 
diff --git a/stack9.4.yaml b/stack9.4.yaml
index 313d64516..9a832dc1d 100644
--- a/stack9.4.yaml
+++ b/stack9.4.yaml
@@ -22,9 +22,6 @@ nix:
   pure: false
   packages: [perl gmp ncurses zlib]
 
-flags:
-  encoding:
-    systemEncoding: false # See https://github.com/dmwit/encoding/issues/26
 
 # ghc-options:
 #   "$locals": -fplugin Debug.Breakpoint
diff --git a/stack9.6.yaml b/stack9.6.yaml
index 653547b02..90aa39239 100644
--- a/stack9.6.yaml
+++ b/stack9.6.yaml
@@ -17,10 +17,6 @@ nix:
   pure: false
   packages: [perl gmp ncurses zlib]
 
-flags:
-  encoding:
-    systemEncoding: false # See https://github.com/dmwit/encoding/issues/26
-
 # ghc-options:
 #   "$locals": -fplugin Debug.Breakpoint
 
diff --git a/stack9.8.yaml b/stack9.8.yaml
index 893081b29..4a794f6eb 100644
--- a/stack9.8.yaml
+++ b/stack9.8.yaml
@@ -16,10 +16,6 @@ nix:
   pure: false
   packages: [perl gmp ncurses zlib]
 
-flags:
-  encoding:
-    systemEncoding: false # See https://github.com/dmwit/encoding/issues/26
-
 # ghc-options:
 #   "$locals": -Wno-x-partial
 #   "$locals": -fplugin Debug.Breakpoint