diff --git a/Makefile b/Makefile
index 873199d0..15bafcbb 100644
--- a/Makefile
+++ b/Makefile
@@ -213,8 +213,8 @@ nfibtest: bin/mhs bin/mhseval
 
 ######
 
-VERSION=0.11.0.0
-HVERSION=0,11,0,0
+VERSION=0.11.1.0
+HVERSION=0,11,1,0
 MCABAL=$(HOME)/.mcabal
 MCABALMHS=$(MCABAL)/mhs-$(VERSION)
 MDATA=$(MCABALMHS)/packages/mhs-$(VERSION)/data
diff --git a/MicroHs.cabal b/MicroHs.cabal
index 32c11d0d..3728000e 100644
--- a/MicroHs.cabal
+++ b/MicroHs.cabal
@@ -1,6 +1,6 @@
 cabal-version:       3.0
 name:                MicroHs
-version:             0.11.0.0
+version:             0.11.1.0
                      -- *** When changing the version number, also
                      -- *** run 'sh updateversion.sh'
                      -- *** Yeah, it stinks.
diff --git a/generated/mhs.c b/generated/mhs.c
index 21eb4406..ddd95e4e 100644
--- a/generated/mhs.c
+++ b/generated/mhs.c
@@ -4914,7 +4914,7 @@ static unsigned char data[] = {
 52,161,18,1,95,50,77,232,1,58,50,77,255,96,190,237,208,5,237,220,
 16,160,174,140,229,224,135,1,8,118,55,46,48,92,49,48,38,34,96,83,
 209,16,0,53,96,144,111,75,64,116,128,19,0,57,66,8,0,48,174,237,
-96,6,128,12,0,48,226,25,0,0,58,96,51,128,45,79,156,0,53,130,
+128,6,96,5,0,48,226,25,0,0,58,96,51,128,45,79,156,0,53,130,
 14,0,85,64,10,193,109,65,231,0,53,65,202,239,36,3,66,148,128,67,
 3,95,50,48,48,65,77,89,128,225,100,0,0,53,208,196,96,60,123,42,
 2,50,53,53,64,157,0,53,129,126,130,99,67,17,162,77,179,202,116,142,
@@ -4923,83 +4923,83 @@ static unsigned char data[] = {
 178,146,241,0,53,110,208,243,50,8,191,12,0,58,96,51,242,242,0,2,
 111,117,116,65,26,208,194,163,4,242,241,0,241,125,35,178,52,177,124,0,
 58,64,140,192,84,85,95,0,80,64,169,64,28,145,11,1,95,52,96,44,
-1,54,32,119,232,88,42,96,15,80,127,0,58,96,98,154,111,96,17,111,
-37,4,97,108,108,111,99,64,16,162,238,0,51,83,37,64,165,147,37,64,
-82,239,159,1,3,95,50,52,51,131,200,1,52,50,222,246,0,58,65,50,
-128,145,1,95,50,68,136,192,207,97,67,64,47,96,153,193,2,64,25,64,
-54,64,13,66,6,121,35,96,69,178,2,3,112,117,116,98,64,130,194,157,
-3,51,55,32,79,64,6,0,56,66,79,147,8,98,80,0,58,96,71,83,
-13,0,50,99,227,0,58,96,26,64,15,111,160,0,58,96,49,96,150,0,
-83,246,125,0,0,90,160,7,128,9,160,10,242,62,3,213,47,230,57,1,
-225,0,5,175,176,1,50,50,66,37,130,99,64,26,81,208,0,51,161,33,
-240,154,4,3,66,97,100,32,157,142,3,32,109,111,100,254,222,0,116,152,
-162,147,0,51,196,151,113,14,0,90,160,4,151,89,241,48,2,100,161,1,
-50,51,66,233,98,214,119,110,241,33,7,64,85,65,52,0,55,84,32,64,
-32,115,117,1,50,112,64,13,162,224,1,52,57,64,193,185,246,224,5,0,
-69,22,127,3,211,25,123,213,1,49,50,166,8,224,6,9,224,42,2,64,
-15,128,48,224,42,30,160,28,224,49,10,224,42,15,224,49,10,224,42,22,
-224,49,3,214,28,97,161,0,58,96,6,227,149,2,70,255,97,145,0,49,
-98,52,130,133,97,96,117,190,66,15,0,58,96,28,194,226,117,137,64,28,
-128,16,67,213,0,50,149,164,87,229,0,58,96,32,228,100,0,0,50,132,
-100,128,52,64,38,3,10,65,32,82,161,95,0,58,96,28,160,138,89,93,
-132,21,0,80,161,226,64,171,67,48,146,242,225,145,2,0,58,96,179,96,
-55,0,85,131,141,66,2,0,73,128,48,198,60,102,251,96,17,163,129,243,
-214,1,0,58,98,228,224,119,2,249,10,2,0,80,158,31,0,49,128,79,
-162,240,179,168,128,148,147,199,2,64,64,64,99,66,0,58,67,242,194,88,
-1,95,50,85,43,161,109,71,146,64,30,129,40,7,115,101,113,117,97,108,
-32,58,96,33,64,46,162,217,3,95,50,49,54,227,47,2,5,77,72,83,
-68,73,82,99,38,0,80,64,78,97,60,226,227,0,1,58,50,191,63,224,
-19,0,230,97,2,0,58,96,45,165,5,195,55,96,203,104,27,150,10,245,
-129,19,247,177,5,1,95,50,127,110,224,126,1,245,135,1,223,171,1,50,
-49,67,102,191,93,11,112,101,101,107,67,65,83,116,114,105,110,103,64,21,
-163,110,1,57,50,103,70,0,58,96,102,227,127,0,133,227,255,191,1,1,
-95,50,104,220,192,6,129,64,96,159,0,58,96,6,6,10,65,32,116,111,
-73,110,70,83,191,135,6,94,103,101,116,101,110,118,64,16,167,152,225,80,
-0,0,52,159,20,225,2,2,245,207,0,166,133,225,81,1,1,95,50,95,
-119,64,102,191,139,65,117,228,193,4,3,116,97,105,108,97,143,0,65,64,
-197,191,165,64,71,65,238,95,141,64,67,98,204,191,180,70,93,191,179,2,
-95,51,48,128,80,96,151,95,106,64,219,69,58,128,56,0,49,75,213,224,
-11,0,224,80,0,0,58,96,6,129,230,0,52,73,33,89,245,160,61,0,
-50,224,155,3,0,101,91,20,0,58,138,40,169,95,96,38,0,58,96,6,
-96,128,251,89,15,6,67,111,110,116,114,111,108,251,87,11,96,18,2,67,
-97,108,128,246,166,107,191,187,102,74,230,73,3,64,7,189,5,190,225,2,
-39,32,95,68,68,138,99,97,109,0,57,100,175,71,174,168,140,137,10,0,
-50,200,152,131,105,0,58,64,165,64,99,118,108,64,14,196,115,232,233,8,
-163,138,232,220,2,0,58,100,123,96,160,0,85,225,193,7,16,109,100,53,
-67,111,109,98,105,110,101,58,32,101,109,112,116,121,134,133,64,143,68,106,
-74,79,160,169,101,32,70,118,185,43,0,56,73,171,64,88,1,64,89,96,
-127,65,11,103,17,68,52,228,25,1,196,176,233,106,2,224,253,3,120,251,
-96,54,72,200,0,49,92,159,98,160,2,52,49,32,157,102,0,95,88,156,
-1,95,49,123,187,160,0,0,58,97,52,66,231,9,109,100,53,65,114,114,
-97,121,32,58,96,57,130,124,194,235,0,55,192,160,1,95,49,92,95,99,
-224,231,175,4,231,67,3,3,95,49,57,53,224,46,5,163,136,251,33,1,
-0,56,129,184,227,32,1,1,95,49,93,9,160,145,226,223,0,96,20,186,
-123,65,0,137,39,67,105,1,53,56,204,223,140,87,151,226,224,106,0,225,
-58,3,192,25,168,133,191,24,0,67,127,5,172,16,94,82,97,34,3,95,
-49,55,55,100,71,128,0,229,148,3,191,91,202,56,232,48,0,64,186,171,
-22,224,44,0,96,95,0,66,133,225,1,51,54,161,125,106,40,255,36,4,
-232,86,4,224,43,10,194,134,229,26,2,96,16,0,58,65,96,226,193,0,
-204,165,0,58,96,135,99,205,99,134,93,141,225,251,0,129,245,0,35,101,
-3,77,160,0,58,97,152,5,10,65,32,35,49,54,65,103,172,182,1,49,
-48,65,232,124,6,92,90,1,95,49,130,49,0,56,78,246,126,30,2,95,
-49,56,192,91,64,11,64,45,160,11,1,57,48,224,11,1,91,48,0,58,
-96,12,255,184,2,137,4,137,7,66,47,160,2,225,58,6,97,170,128,50,
-161,237,165,193,134,58,111,15,159,252,96,15,96,164,125,231,174,160,93,173,
-64,33,131,66,224,33,7,192,139,0,95,77,167,224,38,16,224,71,25,6,
-64,64,83,32,73,32,64,142,242,192,84,224,194,0,67,167,0,83,162,121,
-96,60,74,46,224,76,16,128,22,99,169,66,135,224,40,16,130,155,195,248,
-97,40,67,83,0,53,224,167,21,129,43,97,172,72,209,65,166,162,57,239,
-179,2,96,27,224,21,1,96,49,0,58,96,140,224,42,2,160,20,221,11,
-239,32,4,0,58,96,113,160,44,64,13,194,159,224,37,7,130,161,225,253,
-0,65,41,74,61,0,50,64,180,76,71,0,58,66,83,195,242,131,183,1,
-95,49,94,140,71,21,66,123,224,27,11,128,114,252,65,6,160,174,220,56,
-1,48,52,69,215,99,10,99,243,65,43,93,231,130,172,1,64,58,98,244,
-137,190,0,49,71,21,225,109,1,0,58,96,39,101,242,128,117,113,155,129,
-218,164,73,79,93,228,136,1,204,84,64,34,1,64,95,78,70,136,134,0,
-48,69,165,1,55,50,230,49,2,27,92,51,52,38,108,105,98,47,68,97,
-116,97,47,73,110,116,101,103,101,114,95,84,121,112,101,46,104,115,64,27,
-4,44,50,56,58,49,241,227,0,96,178,99,159,97,78,0,85,161,215,224,
-18,0,240,78,3,3,79,32,35,50,244,14,2,224,60,3,105,109,96,60,
+0,54,97,194,67,26,115,232,85,88,64,38,129,170,2,73,32,58,96,17,
+111,37,4,97,108,108,111,99,64,16,162,238,0,51,83,37,64,165,147,37,
+64,82,239,159,1,3,95,50,52,51,131,200,1,52,50,222,246,0,58,65,
+50,128,145,1,95,50,68,136,192,207,97,67,64,47,96,153,193,2,64,25,
+64,54,64,13,66,6,121,35,96,69,178,2,3,112,117,116,98,64,130,194,
+157,3,51,55,32,79,64,6,0,56,66,79,147,8,98,80,0,58,96,71,
+83,13,0,50,99,227,0,58,96,26,64,15,111,160,0,58,96,49,96,150,
+0,83,246,125,0,0,90,160,7,128,9,160,10,242,62,3,213,47,230,57,
+1,225,0,5,175,176,1,50,50,66,37,130,99,64,26,81,208,0,51,161,
+33,240,154,4,3,66,97,100,32,157,142,3,32,109,111,100,254,222,0,116,
+152,162,147,0,51,196,151,113,14,0,90,160,4,151,89,241,48,2,100,161,
+1,50,51,66,233,98,214,119,110,241,33,7,64,85,65,52,0,55,84,32,
+64,32,115,117,1,50,112,64,13,162,224,1,52,57,64,193,185,246,224,5,
+0,69,22,127,3,211,25,123,213,1,49,50,166,8,224,6,9,224,42,2,
+64,15,128,48,224,42,30,160,28,224,49,10,224,42,15,224,49,10,224,42,
+22,224,49,3,214,28,97,161,0,58,96,6,227,149,2,70,255,97,145,0,
+49,98,52,130,133,97,96,117,190,66,15,0,58,96,28,194,226,117,137,64,
+28,128,16,67,213,0,50,149,164,87,229,0,58,96,32,228,100,0,0,50,
+132,100,128,52,64,38,3,10,65,32,82,161,95,0,58,96,28,160,138,89,
+93,132,21,0,80,161,226,64,171,67,48,146,242,225,145,2,0,58,96,179,
+96,55,0,85,131,141,66,2,0,73,128,48,198,60,102,251,96,17,163,129,
+243,214,1,0,58,98,228,224,119,2,249,10,2,0,80,158,31,0,49,128,
+79,162,240,179,168,128,148,147,199,2,64,64,64,99,66,0,58,67,242,194,
+88,1,95,50,85,43,161,109,71,146,64,30,129,40,7,115,101,113,117,97,
+108,32,58,96,33,64,46,162,217,3,95,50,49,54,227,47,2,5,77,72,
+83,68,73,82,99,38,0,80,64,78,97,60,226,227,0,1,58,50,191,63,
+224,19,0,230,97,2,0,58,96,45,165,5,195,55,96,203,104,27,150,10,
+245,129,19,247,177,5,1,95,50,127,110,224,126,1,245,135,1,223,171,1,
+50,49,67,102,191,93,11,112,101,101,107,67,65,83,116,114,105,110,103,64,
+21,163,110,1,57,50,103,70,0,58,96,102,227,127,0,133,227,255,191,1,
+1,95,50,104,220,192,6,129,64,96,159,0,58,96,6,6,10,65,32,116,
+111,73,110,70,83,191,135,6,94,103,101,116,101,110,118,64,16,167,152,225,
+80,0,0,52,159,20,225,2,2,245,207,0,166,133,225,81,1,1,95,50,
+95,119,64,102,191,139,65,117,228,193,4,3,116,97,105,108,97,143,0,65,
+64,197,191,165,64,71,65,238,95,141,64,67,98,204,191,180,70,93,191,179,
+2,95,51,48,128,80,96,151,95,106,64,219,69,58,128,56,0,49,75,213,
+224,11,0,224,80,0,0,58,96,6,129,230,0,52,73,33,89,245,160,61,
+0,50,224,155,3,0,101,91,20,0,58,138,40,169,95,96,38,0,58,96,
+6,96,128,251,89,15,6,67,111,110,116,114,111,108,251,87,11,96,18,2,
+67,97,108,128,246,166,107,191,187,102,74,230,73,3,64,7,189,5,190,225,
+2,39,32,95,68,68,138,99,97,109,0,57,100,175,71,174,168,140,137,10,
+0,50,200,152,131,105,0,58,64,165,64,99,118,108,64,14,196,115,232,233,
+8,163,138,232,220,2,0,58,100,123,96,160,0,85,225,193,7,16,109,100,
+53,67,111,109,98,105,110,101,58,32,101,109,112,116,121,134,133,64,143,68,
+106,74,79,160,169,101,32,70,118,185,43,0,56,73,171,64,88,1,64,89,
+96,127,65,11,103,17,68,52,228,25,1,196,176,233,106,2,224,253,3,120,
+251,96,54,72,200,0,49,92,159,98,160,2,52,49,32,157,102,0,95,88,
+156,1,95,49,123,187,160,0,0,58,97,52,66,231,9,109,100,53,65,114,
+114,97,121,32,58,96,57,130,124,194,235,0,55,192,160,1,95,49,92,95,
+99,224,231,175,4,231,67,3,3,95,49,57,53,224,46,5,163,136,251,33,
+1,0,56,129,184,227,32,1,1,95,49,93,9,160,145,226,223,0,96,20,
+186,123,65,0,137,39,67,105,1,53,56,204,223,140,87,151,226,224,106,0,
+225,58,3,192,25,168,133,191,24,0,67,127,5,172,16,94,82,97,34,3,
+95,49,55,55,100,71,128,0,229,148,3,191,91,202,56,232,48,0,64,186,
+171,22,224,44,0,96,95,0,66,133,225,1,51,54,161,125,106,40,255,36,
+4,232,86,4,224,43,10,194,134,229,26,2,96,16,0,58,65,96,226,193,
+0,204,165,0,58,96,135,99,205,99,134,93,141,225,251,0,129,245,0,35,
+101,3,77,160,0,58,97,152,5,10,65,32,35,49,54,65,103,172,182,1,
+49,48,65,232,124,6,92,90,1,95,49,130,49,0,56,78,246,126,30,2,
+95,49,56,192,91,64,11,64,45,160,11,1,57,48,224,11,1,91,48,0,
+58,96,12,255,184,2,137,4,137,7,66,47,160,2,225,58,6,97,170,128,
+50,161,237,165,193,134,58,111,15,159,252,96,15,96,164,125,231,174,160,93,
+173,64,33,131,66,224,33,7,192,139,0,95,77,167,224,38,16,224,71,25,
+6,64,64,83,32,73,32,64,142,242,192,84,224,194,0,67,167,0,83,162,
+121,96,60,74,46,224,76,16,128,22,99,169,66,135,224,40,16,130,155,195,
+248,97,40,67,83,0,53,224,167,21,129,43,97,172,72,209,65,166,162,57,
+239,179,2,96,27,224,21,1,96,49,0,58,96,140,224,42,2,160,20,221,
+11,239,32,4,0,58,96,113,160,44,64,13,194,159,224,37,7,130,161,225,
+253,0,65,41,74,61,0,50,64,180,76,71,0,58,66,83,195,242,131,183,
+1,95,49,94,140,71,21,66,123,224,27,11,128,114,252,65,6,160,174,220,
+56,1,48,52,69,215,99,10,99,243,65,43,93,231,130,172,1,64,58,98,
+244,137,190,0,49,71,21,225,109,1,0,58,96,39,101,242,128,117,113,155,
+129,218,164,73,79,93,228,136,1,204,84,64,34,1,64,95,78,70,136,134,
+0,48,69,165,1,55,50,230,49,2,27,92,51,52,38,108,105,98,47,68,
+97,116,97,47,73,110,116,101,103,101,114,95,84,121,112,101,46,104,115,64,
+27,4,44,50,56,58,49,241,227,0,96,178,99,159,97,78,0,85,161,215,
+224,18,0,240,91,0,128,5,0,50,244,14,2,224,60,3,105,109,96,60,
 0,89,160,208,67,155,64,197,0,48,192,197,158,168,100,166,65,15,100,4,
 146,3,196,214,98,102,128,18,228,167,1,3,64,95,52,52,133,61,0,58,
 97,85,7,10,65,32,114,101,109,32,58,96,64,110,48,0,58,96,126,79,
diff --git a/lib/AllOfLib.hs b/lib/AllOfLib.hs
index d68818e5..a21164e8 100644
--- a/lib/AllOfLib.hs
+++ b/lib/AllOfLib.hs
@@ -23,6 +23,7 @@ import Data.Bounded
 import Data.ByteString
 import Data.Char
 import Data.Char_Type
+import Data.Coerce
 import Data.Complex
 import Data.Constraint
 import Data.Dynamic
diff --git a/lib/libs.cabal b/lib/libs.cabal
index b8970ca3..9504c9d3 100644
--- a/lib/libs.cabal
+++ b/lib/libs.cabal
@@ -1,6 +1,6 @@
 cabal-version:  3.0
 name:           libs
-version:        0.11.0.0
+version:        0.11.1.0
 license:        Apache
 license-file:   LICENSE
 maintainer:     lennart@augustsson.net
@@ -34,6 +34,7 @@ library base
         Data.Bounded
         Data.ByteString
         Data.Char
+        Data.Coerce
         Data.Complex
         Data.Constraint
         Data.Data
diff --git a/paths/Paths_MicroHs.hs b/paths/Paths_MicroHs.hs
index 86cf5488..3a5e8f01 100644
--- a/paths/Paths_MicroHs.hs
+++ b/paths/Paths_MicroHs.hs
@@ -10,4 +10,4 @@ getDataDir :: IO FilePath
 getDataDir = return "."
 
 version :: Version
-version = makeVersion [0,11,0,0]
+version = makeVersion [0,11,1,0]
diff --git a/src/MicroHs/TypeCheck.hs b/src/MicroHs/TypeCheck.hs
index 9abe9ade..0d5451f2 100644
--- a/src/MicroHs/TypeCheck.hs
+++ b/src/MicroHs/TypeCheck.hs
@@ -3018,8 +3018,12 @@ extNewtypeSyns :: T ()
 extNewtypeSyns = do
   dt <- gets dataTable
   mn <- gets moduleName
-  let ext (Newtype (i, vs) (Constr _ _ _ et) _) = extSyn (qualIdent mn i) (EForall True vs t)
-          where t = either (snd . head) (snd . snd . head) et
+  let ext (Newtype (i, vs) (Constr _ _ _c et) _) = do
+          -- XXX We should check that the constructor name (_c) is visible.
+          -- But this is tricky since we don't know under what qualified name it
+          -- it should be visible.
+          let t = either (snd . head) (snd . snd . head) et
+          extSyn (qualIdent mn i) (EForall True vs t)  -- extend synonym table
       ext _ = return ()
   mapM_ ext $ M.elems dt