diff --git a/.hlint.yaml b/.hlint.yaml
index a41958d886d..d9532dcc200 100644
--- a/.hlint.yaml
+++ b/.hlint.yaml
@@ -27,3 +27,4 @@
 - ignore: {name: Use first, within: [UntypedPlutusCore.Evaluation.Machine.Cek]}
 - ignore: {name: Redundant if, within: [PlutusLedgerApi.V1.Value, PlutusLedgerApi.V1.Data.Value]}
 - ignore: {name: Replace case with maybe, within: [PlutusLedgerApi.V1.Value, PlutusLedgerApi.V1.Data.Value]}
+- ignore: {name: Use bimap, within: [PlutusTx.Builtins.HasOpaque]}
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/bls12_381_G1_scalarMul/mul-neg-one/mul-neg-one.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/bls12_381_G1_scalarMul/mul-neg-one/mul-neg-one.uplc.budget.expected
new file mode 100644
index 00000000000..1f875e2ed21
--- /dev/null
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/bls12_381_G1_scalarMul/mul-neg-one/mul-neg-one.uplc.budget.expected
@@ -0,0 +1,2 @@
+({cpu: 76521974
+| mem: 618})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/bls12_381_G1_scalarMul/mul-neg-one/mul-neg-one.uplc.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/bls12_381_G1_scalarMul/mul-neg-one/mul-neg-one.uplc.expected
new file mode 100644
index 00000000000..c53839615ce
--- /dev/null
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/bls12_381_G1_scalarMul/mul-neg-one/mul-neg-one.uplc.expected
@@ -0,0 +1,7 @@
+(program
+  1.0.0
+  (con
+    bls12_381_G1_element
+    0x8bd61864f519748032551e42e0ac417fd828f079454e3e3c9891c5c29ed7f10bdecc046854e3931cb7002779bd76d71f
+  )
+)
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/replicateByte/case-07/case-07.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/replicateByte/case-07/case-07.uplc.budget.expected
index c87df86098c..efb388a633c 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/replicateByte/case-07/case-07.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/replicateByte/case-07/case-07.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 260294
-| mem: 601})
\ No newline at end of file
+({cpu: 260453
+| mem: 602})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/replicateByte/case-09/case-09.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/replicateByte/case-09/case-09.uplc.budget.expected
index cf9145bf677..efb388a633c 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/replicateByte/case-09/case-09.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/replicateByte/case-09/case-09.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 423110
-| mem: 1625})
\ No newline at end of file
+({cpu: 260453
+| mem: 602})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-11/case-11.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-11/case-11.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-11/case-11.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-11/case-11.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-12/case-12.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-12/case-12.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-12/case-12.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-12/case-12.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-13/case-13.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-13/case-13.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-13/case-13.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-13/case-13.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-14/case-14.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-14/case-14.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-14/case-14.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-14/case-14.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-15/case-15.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-15/case-15.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-15/case-15.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-15/case-15.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-16/case-16.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-16/case-16.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-16/case-16.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-16/case-16.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-17/case-17.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-17/case-17.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-17/case-17.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-17/case-17.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-18/case-18.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-18/case-18.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-18/case-18.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-18/case-18.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-20/case-20.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-20/case-20.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-20/case-20.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-20/case-20.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-21/case-21.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-21/case-21.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-21/case-21.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-21/case-21.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-22/case-22.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-22/case-22.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-22/case-22.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-22/case-22.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-23/case-23.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-23/case-23.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-23/case-23.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-23/case-23.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-24/case-24.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-24/case-24.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-24/case-24.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-24/case-24.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-25/case-25.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-25/case-25.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-25/case-25.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-25/case-25.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-26/case-26.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-26/case-26.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-26/case-26.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-26/case-26.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-27/case-27.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-27/case-27.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-27/case-27.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-27/case-27.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-29/case-29.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-29/case-29.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-29/case-29.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-29/case-29.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-30/case-30.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-30/case-30.uplc.budget.expected
index 30dac2d1008..a1c5da50f2b 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-30/case-30.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-30/case-30.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 430941
+({cpu: 562877
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-31/case-31.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-31/case-31.uplc.budget.expected
index 30dac2d1008..a1c5da50f2b 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-31/case-31.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-31/case-31.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 430941
+({cpu: 562877
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-32/case-32.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-32/case-32.uplc.budget.expected
index 1abc268e00a..859038aac2b 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-32/case-32.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-32/case-32.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 732509
+({cpu: 1769149
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-33/case-33.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-33/case-33.uplc.budget.expected
index 1abc268e00a..859038aac2b 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-33/case-33.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-33/case-33.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 732509
+({cpu: 1769149
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-34/case-34.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-34/case-34.uplc.budget.expected
index d51c314bbff..dc3bad8c412 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-34/case-34.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-34/case-34.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 808086
+({cpu: 958870
 | mem: 1402})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-35/case-35.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-35/case-35.uplc.budget.expected
index d51c314bbff..dc3bad8c412 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-35/case-35.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-35/case-35.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 808086
+({cpu: 958870
 | mem: 1402})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-36/case-36.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-36/case-36.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-36/case-36.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-36/case-36.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-37/case-37.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-37/case-37.uplc.budget.expected
index 927839980d3..4ef433525a7 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-37/case-37.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-37/case-37.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 412093
+({cpu: 487485
 | mem: 801})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-38/case-38.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-38/case-38.uplc.budget.expected
index c6aac0b723f..d454b574d76 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-38/case-38.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-38/case-38.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 449789
+({cpu: 638269
 | mem: 806})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-39/case-39.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-39/case-39.uplc.budget.expected
index 07b22130740..244947ff0d0 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-39/case-39.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-39/case-39.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 940022
+({cpu: 1486614
 | mem: 1412})
\ No newline at end of file
diff --git a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-40/case-40.uplc.budget.expected b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-40/case-40.uplc.budget.expected
index c6aac0b723f..d454b574d76 100644
--- a/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-40/case-40.uplc.budget.expected
+++ b/plutus-conformance/test-cases/uplc/evaluation/builtin/semantics/writeBits/case-40/case-40.uplc.budget.expected
@@ -1,2 +1,2 @@
-({cpu: 449789
+({cpu: 638269
 | mem: 806})
\ No newline at end of file
diff --git a/plutus-core/cost-model/test/TH.hs b/plutus-core/cost-model/test/TH.hs
index ea849584b16..e193400d399 100644
--- a/plutus-core/cost-model/test/TH.hs
+++ b/plutus-core/cost-model/test/TH.hs
@@ -3,17 +3,14 @@
    restrictions.
 -}
 
-{-# LANGUAGE TemplateHaskell #-}
-
-module TH (genTest)
-where
+module TH (genTest) where
 
 import Data.Char (toUpper)
 import Language.Haskell.TH
 
 toUpper1 :: String -> String
 toUpper1 []     = error "empty string in toUpper1"
-toUpper1 (c:cs) = (toUpper c):cs
+toUpper1 (c:cs) = toUpper c : cs
 
 mkIterApp :: Exp -> [Exp] -> Exp
 mkIterApp = foldl AppE
diff --git a/plutus-tx-plugin/plutus-tx-plugin.cabal b/plutus-tx-plugin/plutus-tx-plugin.cabal
index b5d191b589c..f36056070ef 100644
--- a/plutus-tx-plugin/plutus-tx-plugin.cabal
+++ b/plutus-tx-plugin/plutus-tx-plugin.cabal
@@ -124,6 +124,7 @@ test-suite plutus-tx-plugin-tests
     Budget.Spec
     Budget.WithGHCOptimisations
     Budget.WithoutGHCOptimisations
+    ByteStringLiterals.Spec
     IntegerLiterals.NoStrict.NegativeLiterals.Spec
     IntegerLiterals.NoStrict.NoNegativeLiterals.Spec
     IntegerLiterals.Strict.NegativeLiterals.Spec
diff --git a/plutus-tx-plugin/src/PlutusTx/Compiler/Expr.hs b/plutus-tx-plugin/src/PlutusTx/Compiler/Expr.hs
index 86f64e3a6b6..d9430093b8b 100644
--- a/plutus-tx-plugin/src/PlutusTx/Compiler/Expr.hs
+++ b/plutus-tx-plugin/src/PlutusTx/Compiler/Expr.hs
@@ -1,8 +1,10 @@
 -- editorconfig-checker-disable-file
+{-# LANGUAGE BangPatterns          #-}
 {-# LANGUAGE CPP                   #-}
 {-# LANGUAGE ConstraintKinds       #-}
 {-# LANGUAGE FlexibleContexts      #-}
 {-# LANGUAGE LambdaCase            #-}
+{-# LANGUAGE MagicHash             #-}
 {-# LANGUAGE MultiWayIf            #-}
 {-# LANGUAGE OverloadedStrings     #-}
 {-# LANGUAGE PartialTypeSignatures #-}
@@ -12,6 +14,7 @@
 {-# LANGUAGE TypeFamilies          #-}
 {-# LANGUAGE TypeOperators         #-}
 {-# LANGUAGE ViewPatterns          #-}
+
 {-# OPTIONS_GHC -Wno-partial-type-signatures #-}
 
 -- | Functions for compiling GHC Core expressions into Plutus Core terms.
@@ -24,6 +27,7 @@ import GHC.Core qualified as GHC
 import GHC.Core.Class qualified as GHC
 import GHC.Core.Multiplicity qualified as GHC
 import GHC.Core.TyCo.Rep qualified as GHC
+import GHC.Num.Integer qualified
 import GHC.Plugins qualified as GHC
 import GHC.Types.CostCentre qualified as GHC
 import GHC.Types.Id.Make qualified as GHC
@@ -76,12 +80,13 @@ import Data.ByteString qualified as BS
 import Data.Generics.Uniplate.Data (transform, universeBi)
 import Data.List (elemIndex, isPrefixOf, isSuffixOf)
 import Data.Map qualified as Map
-import Data.Maybe
+import Data.Maybe (mapMaybe)
 import Data.Set qualified as Set
 import Data.Text qualified as T
 import Data.Text.Encoding qualified as TE
-import Data.Traversable
-import GHC.Num.Integer qualified
+import Data.Traversable (for)
+import Data.Word (Word8)
+
 
 {- Note [System FC and System FW]
 Haskell uses system FC, which includes type equalities and coercions.
@@ -136,23 +141,51 @@ compileLiteral = \case
 -- do different things to the inner expression. This one assumes it's a literal, the other one keeps compiling
 -- through it.
 
--- | Get the bytestring content of a string expression, if possible. Follows (Haskell) variable references!
-stringExprContent :: GHC.CoreExpr -> Maybe BS.ByteString
-stringExprContent = \case
-  GHC.Lit (GHC.LitString bs) -> Just bs
-  -- unpackCString# / unpackCStringUtf8# are just wrappers around a literal
-  GHC.Var n `GHC.App` expr
-    | let name = GHC.getName n
-    , name == GHC.unpackCStringName || name == GHC.unpackCStringUtf8Name ->
-      stringExprContent expr
+data StringExprContentAs = AsBytes | AsText
+
+-- | Get the bytestring content of a string expression, if possible.
+-- Follows (Haskell) variable references!
+stringExprContent :: StringExprContentAs -> GHC.CoreExpr -> Maybe BS.ByteString
+stringExprContent contentAs coreExpr = case coreExpr of
+  GHC.Lit (GHC.LitString bytes) ->
+    Just bytes
+  GHC.Var isUnpackCString `GHC.App` GHC.Lit (GHC.LitString bytes)
+    | GHC.getName isUnpackCString == GHC.unpackCStringName ->
+        Just bytes
+  GHC.Var isUnpackCStringUtf8 `GHC.App` GHC.Lit (GHC.LitString bytes)
+    | GHC.getName isUnpackCStringUtf8 == GHC.unpackCStringUtf8Name ->
+    case contentAs of
+      AsText -> Just bytes
+      AsBytes ->
+        -- GHC stores bytestring literals UTF-8 encoded, decoding them at runtime.
+        -- In Plinth we decode such bytestrings in compile-time.
+        BS.pack <$> fromUtf8 (BS.unpack bytes)
   -- See Note [unpackFoldrCString#]
   GHC.Var build `GHC.App` _ `GHC.App` GHC.Lam _ (GHC.Var unpack `GHC.App` _ `GHC.App` expr)
-    | GHC.getName build == GHC.buildName && GHC.getName unpack == GHC.unpackCStringFoldrName -> stringExprContent expr
+    | GHC.getName build == GHC.buildName && GHC.getName unpack == GHC.unpackCStringFoldrName ->
+      stringExprContent contentAs expr
   -- GHC helpfully generates an empty list for the empty string literal instead of a 'LitString'
   GHC.Var nil `GHC.App` GHC.Type (GHC.tyConAppTyCon_maybe -> Just tc)
-    | nil == GHC.dataConWorkId GHC.nilDataCon, GHC.getName tc == GHC.charTyConName -> Just mempty
-  -- Chase variable references! GHC likes to lift string constants to variables, that is not good for us!
-  GHC.Var (GHC.maybeUnfoldingTemplate . GHC.realIdUnfolding -> Just unfolding) -> stringExprContent unfolding
+    | nil == GHC.dataConWorkId GHC.nilDataCon, GHC.getName tc == GHC.charTyConName ->
+      Just mempty
+  -- Chase variable references! GHC likes to lift string constants to variables,
+  -- that is not good for us!
+  GHC.Var (GHC.maybeUnfoldingTemplate . GHC.realIdUnfolding -> Just unfolding) ->
+    stringExprContent contentAs unfolding
+  _ -> Nothing
+
+{- | Decoding that undoes GHC's UTF-8 encoding of bytestring literals:
+
+This isn't a full UTF-8 decoder: it only decodes the subset of UTF-8 that
+is expected to be found in bytestring literals: 0x00 - 0xFF
+-}
+fromUtf8 :: [Word8] -> Maybe [Word8]
+fromUtf8 = \case
+  [] -> Just []
+  192 : 128 : rest -> (0x00 :) <$> fromUtf8 rest
+  194 : b : rest | b > 127 && b < 192 -> (b :) <$> fromUtf8 rest
+  195 : b : rest | b > 127 && b < 192 -> ((b + 64) :) <$> fromUtf8 rest
+  b : rest | b > 0 && b < 128 -> (b :) <$> fromUtf8 rest
   _ -> Nothing
 
 {- | Strip off irrelevant things when we're trying to match a particular pattern in the code. Mostly ticks.
@@ -699,13 +732,21 @@ compileExpr e = traceCompilation 2 ("Compiling expr:" GHC.<+> GHC.ppr e) $ do
     _                             -> throwPlain $ CompilationError "No info for Pair builtin"
 
   -- TODO: Maybe share this to avoid repeated lookups. Probably cheap, though.
-  (stringTyName, sbsName) <- case (Map.lookup ''Builtins.BuiltinString nameInfo, Map.lookup 'Builtins.stringToBuiltinString nameInfo) of
+  (stringTyName, sbsName) <-
+    case
+      ( Map.lookup ''Builtins.BuiltinString nameInfo
+      , Map.lookup 'Builtins.stringToBuiltinString nameInfo
+      ) of
     (Just t1, Just t2) -> pure (GHC.getName t1, GHC.getName t2)
     _                  -> throwPlain $ CompilationError "No info for String builtin"
 
-  (bsTyName, sbbsName) <- case (Map.lookup ''Builtins.BuiltinByteString nameInfo, Map.lookup 'Builtins.stringToBuiltinByteString nameInfo) of
-    (Just t1, Just t2) -> pure (GHC.getName t1, GHC.getName t2)
-    _                  -> throwPlain $ CompilationError "No info for ByteString builtin"
+  (builtinByteStringTyName, sbbsName) <-
+    case
+      ( Map.lookup ''Builtins.BuiltinByteString nameInfo
+      , Map.lookup 'Builtins.stringToBuiltinByteString nameInfo
+      ) of
+      (Just t1, Just t2) -> pure (GHC.getName t1, GHC.getName t2)
+      _                  -> throwPlain $ CompilationError "No info for ByteString builtin"
 
   useToOpaqueName <- GHC.getName <$> getThing 'Builtins.useToOpaque
   useFromOpaqueName <- GHC.getName <$> getThing 'Builtins.useFromOpaque
@@ -730,39 +771,54 @@ compileExpr e = traceCompilation 2 ("Compiling expr:" GHC.<+> GHC.ppr e) $ do
     -- to know we're looking at fromString.
     -- We can safely commit to this match as soon as we've seen fromString - we won't accept
     -- any applications of fromString that aren't creating literals of our builtin types.
-    (strip -> GHC.Var (GHC.idDetails -> GHC.ClassOpId cls)) `GHC.App` GHC.Type ty `GHC.App` _ `GHC.App` content
+    (strip -> GHC.Var (GHC.idDetails -> GHC.ClassOpId cls))
+      `GHC.App` GHC.Type ty `GHC.App` _dict `GHC.App` content
       | GHC.getName cls == GHC.isStringClassName ->
-          case GHC.tyConAppTyCon_maybe ty of
-            Just tc -> case stringExprContent (strip content) of
-              Just bs ->
-                if
-                    | GHC.getName tc == bsTyName -> pure $ PIR.Constant annMayInline $ PLC.someValue bs
-                    | GHC.getName tc == stringTyName -> case TE.decodeUtf8' bs of
-                        Right t -> pure $ PIR.Constant annMayInline $ PLC.someValue t
-                        Left err ->
-                          throwPlain . CompilationError $
-                            "Text literal with invalid UTF-8 content: " <> (T.pack $ show err)
-                    | otherwise ->
-                        throwSd UnsupportedError $
-                          "Use of fromString on type other than builtin strings or bytestrings:" GHC.<+> GHC.ppr ty
-              Nothing ->
-                throwSd CompilationError $
-                  "Use of fromString with inscrutable content:" GHC.<+> GHC.ppr content
+          case GHC.tyConAppTyCon_maybe ty of -- extract Type constructor without arguments
+            Just tc ->
+              if
+                | GHC.getName tc == builtinByteStringTyName ->
+                    case stringExprContent AsBytes (strip content) of
+                      Nothing ->
+                        throwSd CompilationError $
+                          "Use of fromString @BuiltinByteString with inscrutable content:"
+                            GHC.<+> GHC.ppr content
+                      Just bs ->
+                        pure $ PIR.Constant annMayInline $ PLC.someValue bs
+                | GHC.getName tc == stringTyName ->
+                    case stringExprContent AsText (strip content) of
+                      Nothing ->
+                        throwSd CompilationError $
+                          "Use of fromString @BuiltinString with inscrutable content:"
+                            GHC.<+> GHC.ppr content
+                      Just bs ->
+                        case TE.decodeUtf8' bs of
+                          Right t -> pure $ PIR.Constant annMayInline $ PLC.someValue t
+                          Left err ->
+                            throwPlain . CompilationError $
+                              "Text literal with invalid UTF-8 content: " <> T.pack (show err)
+                | otherwise ->
+                    throwSd UnsupportedError $
+                      "Use of fromString on type other than builtin strings or bytestrings:"
+                        GHC.<+> GHC.ppr ty
             Nothing ->
               throwSd UnsupportedError $
-                "Use of fromString on type other than builtin strings or bytestrings:" GHC.<+> GHC.ppr ty
+                "Use of fromString on type other than builtin strings or bytestrings:"
+                  GHC.<+> GHC.ppr ty
+
     -- 'stringToBuiltinByteString' invocation
-    (strip -> GHC.Var n) `GHC.App` (strip -> stringExprContent -> Just bs)
+    (strip -> GHC.Var n) `GHC.App` (strip -> stringExprContent AsBytes -> Just bs)
       | GHC.getName n == sbbsName ->
           pure $ PIR.Constant annMayInline $ PLC.someValue bs
     -- 'stringToBuiltinString' invocation
-    (strip -> GHC.Var n) `GHC.App` (strip -> stringExprContent -> Just bs) | GHC.getName n == sbsName ->
-      case TE.decodeUtf8' bs of
-        Right t -> pure $ PIR.Constant annMayInline $ PLC.someValue t
-        Left err ->
-          throwPlain $
-            CompilationError $
-              "Text literal with invalid UTF-8 content: " <> (T.pack $ show err)
+    (strip -> GHC.Var n) `GHC.App` (strip -> stringExprContent AsText -> Just bs)
+      | GHC.getName n == sbsName ->
+        case TE.decodeUtf8' bs of
+          Right t -> pure $ PIR.Constant annMayInline $ PLC.someValue t
+          Left err ->
+            throwPlain $
+              CompilationError $
+                "Text literal with invalid UTF-8 content: " <> (T.pack $ show err)
     -- See Note [Literals]
     GHC.Lit lit -> compileLiteral lit
     -- These are all wrappers around string and char literals, but keeping them allows us to give better errors
diff --git a/plutus-tx-plugin/test/AssocMap/Spec.hs b/plutus-tx-plugin/test/AssocMap/Spec.hs
index 04e4f2604c2..228b18bae87 100644
--- a/plutus-tx-plugin/test/AssocMap/Spec.hs
+++ b/plutus-tx-plugin/test/AssocMap/Spec.hs
@@ -91,21 +91,23 @@ map2 =
         \n ->
           let m1 =
                 Data.AssocMap.unsafeFromList
-                  [ (n PlutusTx.+ 1, "one")
-                  , (n PlutusTx.+ 2, "two")
-                  , (n PlutusTx.+ 3, "three")
-                  , (n PlutusTx.+ 4, "four")
-                  , (n PlutusTx.+ 5, "five")
+                  [ (n PlutusTx.+ 1, "\1")
+                  , (n PlutusTx.+ 2, "\2")
+                  , (n PlutusTx.+ 3, "\3")
+                  , (n PlutusTx.+ 4, "\4")
+                  , (n PlutusTx.+ 5, "\5")
                   ]
               m2 =
                 Data.AssocMap.unsafeFromList
-                  [ (n PlutusTx.+ 3, "THREE")
-                  , (n PlutusTx.+ 4, "FOUR")
-                  , (n PlutusTx.+ 6, "SIX")
-                  , (n PlutusTx.+ 7, "SEVEN")
+                  [ (n PlutusTx.+ 3, "\33")
+                  , (n PlutusTx.+ 4, "\44")
+                  , (n PlutusTx.+ 6, "\66")
+                  , (n PlutusTx.+ 7, "\77")
                   ]
               m = Data.AssocMap.unionWith PlutusTx.appendByteString m1 m2
-           in PlutusTx.fmap (\(k, v) -> (k, PlutusTx.decodeUtf8 v)) (Data.AssocMap.toList m)
+           in PlutusTx.fmap
+                (\(k, v) -> (k, PlutusTx.decodeUtf8 v))
+                (Data.AssocMap.toList m)
         ||]
     )
 
diff --git a/plutus-tx-plugin/test/Budget/9.6/map2-budget.budget.golden b/plutus-tx-plugin/test/Budget/9.6/map2-budget.budget.golden
index 432791a44b6..99d8f785118 100644
--- a/plutus-tx-plugin/test/Budget/9.6/map2-budget.budget.golden
+++ b/plutus-tx-plugin/test/Budget/9.6/map2-budget.budget.golden
@@ -1,2 +1,2 @@
-({cpu: 138097368
-| mem: 465626})
\ No newline at end of file
+({cpu: 138096599
+| mem: 465624})
\ No newline at end of file
diff --git a/plutus-tx-plugin/test/Budget/9.6/map2.eval.golden b/plutus-tx-plugin/test/Budget/9.6/map2.eval.golden
index e8e3b12565c..ca61111946b 100644
--- a/plutus-tx-plugin/test/Budget/9.6/map2.eval.golden
+++ b/plutus-tx-plugin/test/Budget/9.6/map2.eval.golden
@@ -1,24 +1,22 @@
 (constr
   1
-  (constr 0 (con integer 105) (con string "five"))
+  (constr 0 (con integer 105) (con string "\ENQ"))
   (constr
     1
-    (constr 0 (con integer 104) (con string "fourFOUR"))
+    (constr 0 (con integer 104) (con string "\EOT,"))
     (constr
       1
-      (constr 0 (con integer 103) (con string "threeTHREE"))
+      (constr 0 (con integer 103) (con string "\ETX!"))
       (constr
         1
-        (constr 0 (con integer 102) (con string "two"))
+        (constr 0 (con integer 102) (con string "\STX"))
         (constr
           1
-          (constr 0 (con integer 101) (con string "one"))
+          (constr 0 (con integer 101) (con string "\SOH"))
           (constr
             1
-            (constr 0 (con integer 106) (con string "SIX"))
-            (constr
-              1 (constr 0 (con integer 107) (con string "SEVEN")) (constr 0)
-            )
+            (constr 0 (con integer 106) (con string "B"))
+            (constr 1 (constr 0 (con integer 107) (con string "M")) (constr 0))
           )
         )
       )
diff --git a/plutus-tx-plugin/test/Budget/9.6/map2.pir.golden b/plutus-tx-plugin/test/Budget/9.6/map2.pir.golden
index 2a8e73cb7e8..42c57b4efc6 100644
--- a/plutus-tx-plugin/test/Budget/9.6/map2.pir.golden
+++ b/plutus-tx-plugin/test/Budget/9.6/map2.pir.golden
@@ -123,25 +123,17 @@ in
              (/\a ->
                 \(c : Tuple2 integer bytestring -> a -> a) (n : a) ->
                   c
-                    (Tuple2 {integer} {bytestring} (addInteger 3 n) #5448524545)
+                    (Tuple2 {integer} {bytestring} (addInteger 3 n) #21)
                     (c
-                       (Tuple2
-                          {integer}
-                          {bytestring}
-                          (addInteger 4 n)
-                          #464f5552)
+                       (Tuple2 {integer} {bytestring} (addInteger 4 n) #2c)
                        (c
-                          (Tuple2
-                             {integer}
-                             {bytestring}
-                             (addInteger 6 n)
-                             #534958)
+                          (Tuple2 {integer} {bytestring} (addInteger 6 n) #42)
                           (c
                              (Tuple2
                                 {integer}
                                 {bytestring}
                                 (addInteger 7 n)
-                                #534556454e)
+                                #4d)
                              n)))))
   in
   letrec
@@ -205,27 +197,23 @@ in
              (/\a ->
                 \(c : Tuple2 integer bytestring -> a -> a) (n : a) ->
                   c
-                    (Tuple2 {integer} {bytestring} (addInteger 1 n) #6f6e65)
+                    (Tuple2 {integer} {bytestring} (addInteger 1 n) #01)
                     (c
-                       (Tuple2 {integer} {bytestring} (addInteger 2 n) #74776f)
+                       (Tuple2 {integer} {bytestring} (addInteger 2 n) #02)
                        (c
-                          (Tuple2
-                             {integer}
-                             {bytestring}
-                             (addInteger 3 n)
-                             #7468726565)
+                          (Tuple2 {integer} {bytestring} (addInteger 3 n) #03)
                           (c
                              (Tuple2
                                 {integer}
                                 {bytestring}
                                 (addInteger 4 n)
-                                #666f7572)
+                                #04)
                              (c
                                 (Tuple2
                                    {integer}
                                    {bytestring}
                                    (addInteger 5 n)
-                                   #66697665)
+                                   #05)
                                 n))))))
   in
   letrec
diff --git a/plutus-tx-plugin/test/Budget/9.6/map2.uplc.golden b/plutus-tx-plugin/test/Budget/9.6/map2.uplc.golden
index 140bc4e7dae..77b4753ceea 100644
--- a/plutus-tx-plugin/test/Budget/9.6/map2.uplc.golden
+++ b/plutus-tx-plugin/test/Budget/9.6/map2.uplc.golden
@@ -97,22 +97,19 @@
                                  (\i -> iData i)
                                  bData
                                  (constr 1
-                                    [ (constr 0 [(addInteger 1 n), #6f6e65])
+                                    [ (constr 0 [(addInteger 1 n), #01])
                                     , (constr 1
-                                         [ (constr 0
-                                              [(addInteger 2 n), #74776f])
+                                         [ (constr 0 [(addInteger 2 n), #02])
                                          , (constr 1
                                               [ (constr 0
-                                                   [ (addInteger 3 n)
-                                                   , #7468726565 ])
+                                                   [(addInteger 3 n), #03])
                                               , (constr 1
                                                    [ (constr 0
-                                                        [ (addInteger 4 n)
-                                                        , #666f7572 ])
+                                                        [(addInteger 4 n), #04])
                                                    , (constr 1
                                                         [ (constr 0
                                                              [ (addInteger 5 n)
-                                                             , #66697665 ])
+                                                             , #05 ])
                                                         , (constr 0
                                                              [  ]) ]) ]) ]) ]) ])))
                            (fix1
@@ -195,15 +192,14 @@
                            (\i -> iData i)
                            bData
                            (constr 1
-                              [ (constr 0 [(addInteger 3 n), #5448524545])
+                              [ (constr 0 [(addInteger 3 n), #21])
                               , (constr 1
-                                   [ (constr 0 [(addInteger 4 n), #464f5552])
+                                   [ (constr 0 [(addInteger 4 n), #2c])
                                    , (constr 1
-                                        [ (constr 0 [(addInteger 6 n), #534958])
+                                        [ (constr 0 [(addInteger 6 n), #42])
                                         , (constr 1
                                              [ (constr 0
-                                                  [ (addInteger 7 n)
-                                                  , #534556454e ])
+                                                  [(addInteger 7 n), #4d])
                                              , (constr 0 []) ]) ]) ]) ])))
                      (\`$dToData` `$dToData` ->
                         (\go eta -> goList (go eta))
diff --git a/plutus-tx-plugin/test/Budget/9.6/map3-budget.budget.golden b/plutus-tx-plugin/test/Budget/9.6/map3-budget.budget.golden
index 432791a44b6..99d8f785118 100644
--- a/plutus-tx-plugin/test/Budget/9.6/map3-budget.budget.golden
+++ b/plutus-tx-plugin/test/Budget/9.6/map3-budget.budget.golden
@@ -1,2 +1,2 @@
-({cpu: 138097368
-| mem: 465626})
\ No newline at end of file
+({cpu: 138096599
+| mem: 465624})
\ No newline at end of file
diff --git a/plutus-tx-plugin/test/Budget/9.6/map3.eval.golden b/plutus-tx-plugin/test/Budget/9.6/map3.eval.golden
index e8e3b12565c..ca61111946b 100644
--- a/plutus-tx-plugin/test/Budget/9.6/map3.eval.golden
+++ b/plutus-tx-plugin/test/Budget/9.6/map3.eval.golden
@@ -1,24 +1,22 @@
 (constr
   1
-  (constr 0 (con integer 105) (con string "five"))
+  (constr 0 (con integer 105) (con string "\ENQ"))
   (constr
     1
-    (constr 0 (con integer 104) (con string "fourFOUR"))
+    (constr 0 (con integer 104) (con string "\EOT,"))
     (constr
       1
-      (constr 0 (con integer 103) (con string "threeTHREE"))
+      (constr 0 (con integer 103) (con string "\ETX!"))
       (constr
         1
-        (constr 0 (con integer 102) (con string "two"))
+        (constr 0 (con integer 102) (con string "\STX"))
         (constr
           1
-          (constr 0 (con integer 101) (con string "one"))
+          (constr 0 (con integer 101) (con string "\SOH"))
           (constr
             1
-            (constr 0 (con integer 106) (con string "SIX"))
-            (constr
-              1 (constr 0 (con integer 107) (con string "SEVEN")) (constr 0)
-            )
+            (constr 0 (con integer 106) (con string "B"))
+            (constr 1 (constr 0 (con integer 107) (con string "M")) (constr 0))
           )
         )
       )
diff --git a/plutus-tx-plugin/test/Budget/9.6/map3.pir.golden b/plutus-tx-plugin/test/Budget/9.6/map3.pir.golden
index 2a8e73cb7e8..42c57b4efc6 100644
--- a/plutus-tx-plugin/test/Budget/9.6/map3.pir.golden
+++ b/plutus-tx-plugin/test/Budget/9.6/map3.pir.golden
@@ -123,25 +123,17 @@ in
              (/\a ->
                 \(c : Tuple2 integer bytestring -> a -> a) (n : a) ->
                   c
-                    (Tuple2 {integer} {bytestring} (addInteger 3 n) #5448524545)
+                    (Tuple2 {integer} {bytestring} (addInteger 3 n) #21)
                     (c
-                       (Tuple2
-                          {integer}
-                          {bytestring}
-                          (addInteger 4 n)
-                          #464f5552)
+                       (Tuple2 {integer} {bytestring} (addInteger 4 n) #2c)
                        (c
-                          (Tuple2
-                             {integer}
-                             {bytestring}
-                             (addInteger 6 n)
-                             #534958)
+                          (Tuple2 {integer} {bytestring} (addInteger 6 n) #42)
                           (c
                              (Tuple2
                                 {integer}
                                 {bytestring}
                                 (addInteger 7 n)
-                                #534556454e)
+                                #4d)
                              n)))))
   in
   letrec
@@ -205,27 +197,23 @@ in
              (/\a ->
                 \(c : Tuple2 integer bytestring -> a -> a) (n : a) ->
                   c
-                    (Tuple2 {integer} {bytestring} (addInteger 1 n) #6f6e65)
+                    (Tuple2 {integer} {bytestring} (addInteger 1 n) #01)
                     (c
-                       (Tuple2 {integer} {bytestring} (addInteger 2 n) #74776f)
+                       (Tuple2 {integer} {bytestring} (addInteger 2 n) #02)
                        (c
-                          (Tuple2
-                             {integer}
-                             {bytestring}
-                             (addInteger 3 n)
-                             #7468726565)
+                          (Tuple2 {integer} {bytestring} (addInteger 3 n) #03)
                           (c
                              (Tuple2
                                 {integer}
                                 {bytestring}
                                 (addInteger 4 n)
-                                #666f7572)
+                                #04)
                              (c
                                 (Tuple2
                                    {integer}
                                    {bytestring}
                                    (addInteger 5 n)
-                                   #66697665)
+                                   #05)
                                 n))))))
   in
   letrec
diff --git a/plutus-tx-plugin/test/Budget/9.6/map3.uplc.golden b/plutus-tx-plugin/test/Budget/9.6/map3.uplc.golden
index 140bc4e7dae..77b4753ceea 100644
--- a/plutus-tx-plugin/test/Budget/9.6/map3.uplc.golden
+++ b/plutus-tx-plugin/test/Budget/9.6/map3.uplc.golden
@@ -97,22 +97,19 @@
                                  (\i -> iData i)
                                  bData
                                  (constr 1
-                                    [ (constr 0 [(addInteger 1 n), #6f6e65])
+                                    [ (constr 0 [(addInteger 1 n), #01])
                                     , (constr 1
-                                         [ (constr 0
-                                              [(addInteger 2 n), #74776f])
+                                         [ (constr 0 [(addInteger 2 n), #02])
                                          , (constr 1
                                               [ (constr 0
-                                                   [ (addInteger 3 n)
-                                                   , #7468726565 ])
+                                                   [(addInteger 3 n), #03])
                                               , (constr 1
                                                    [ (constr 0
-                                                        [ (addInteger 4 n)
-                                                        , #666f7572 ])
+                                                        [(addInteger 4 n), #04])
                                                    , (constr 1
                                                         [ (constr 0
                                                              [ (addInteger 5 n)
-                                                             , #66697665 ])
+                                                             , #05 ])
                                                         , (constr 0
                                                              [  ]) ]) ]) ]) ]) ])))
                            (fix1
@@ -195,15 +192,14 @@
                            (\i -> iData i)
                            bData
                            (constr 1
-                              [ (constr 0 [(addInteger 3 n), #5448524545])
+                              [ (constr 0 [(addInteger 3 n), #21])
                               , (constr 1
-                                   [ (constr 0 [(addInteger 4 n), #464f5552])
+                                   [ (constr 0 [(addInteger 4 n), #2c])
                                    , (constr 1
-                                        [ (constr 0 [(addInteger 6 n), #534958])
+                                        [ (constr 0 [(addInteger 6 n), #42])
                                         , (constr 1
                                              [ (constr 0
-                                                  [ (addInteger 7 n)
-                                                  , #534556454e ])
+                                                  [(addInteger 7 n), #4d])
                                              , (constr 0 []) ]) ]) ]) ])))
                      (\`$dToData` `$dToData` ->
                         (\go eta -> goList (go eta))
diff --git a/plutus-tx-plugin/test/ByteStringLiterals/Spec.hs b/plutus-tx-plugin/test/ByteStringLiterals/Spec.hs
new file mode 100644
index 00000000000..dbf9197d07d
--- /dev/null
+++ b/plutus-tx-plugin/test/ByteStringLiterals/Spec.hs
@@ -0,0 +1,114 @@
+{-# LANGUAGE BlockArguments    #-}
+{-# LANGUAGE DataKinds         #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE TemplateHaskell   #-}
+{-# LANGUAGE TypeApplications  #-}
+
+module ByteStringLiterals.Spec (tests) where
+
+import Data.ByteString (ByteString)
+import Data.Char (chr)
+import Data.Foldable (for_)
+import Data.String (fromString)
+import PlutusPrelude (display)
+import PlutusTx (CompiledCode, getPlcNoAnn)
+import PlutusTx.Builtins (BuiltinByteString, fromBuiltin)
+import PlutusTx.Builtins.HasOpaque (stringToBuiltinByteString)
+import PlutusTx.TH (compile)
+import Test.Tasty (TestTree, testGroup)
+import Test.Tasty.HUnit (testCase, (@?=))
+import UntypedPlutusCore (Program (_progTerm))
+
+tests :: TestTree
+tests =
+  testGroup
+    "ByteStringLiterals"
+    [ test_FromString
+    , testGroup
+        "Compile BuiltinByteString Literal"
+        [ test_CompileBuiltinByteStringLiteral_IsString
+        , test_CompileBuiltinByteStringLiteral_StringToBuiltinByteString
+        ]
+    ]
+
+test_FromString :: TestTree
+test_FromString = testCase "fromString" do
+  for_ [0x00 .. 0xFF] \(i :: Int) -> do
+    let s :: String = [chr i]
+    fromBuiltin (fromString @BuiltinByteString s) @?= fromString @ByteString s
+
+test_CompileBuiltinByteStringLiteral_IsString :: TestTree
+test_CompileBuiltinByteStringLiteral_IsString =
+  testCase "OverloadedStrings" do
+    display (_progTerm (getPlcNoAnn compiledLiteral)) @?= expectedUplc
+  where
+    compiledLiteral :: CompiledCode BuiltinByteString =
+      $$( compile
+            [||
+            "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F\
+            \\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1A\x1B\x1C\x1D\x1E\x1F\
+            \\x20\x21\x22\x23\x24\x25\x26\x27\x28\x29\x2A\x2B\x2C\x2D\x2E\x2F\
+            \\x30\x31\x32\x33\x34\x35\x36\x37\x38\x39\x3A\x3B\x3C\x3D\x3E\x3F\
+            \\x40\x41\x42\x43\x44\x45\x46\x47\x48\x49\x4A\x4B\x4C\x4D\x4E\x4F\
+            \\x50\x51\x52\x53\x54\x55\x56\x57\x58\x59\x5A\x5B\x5C\x5D\x5E\x5F\
+            \\x60\x61\x62\x63\x64\x65\x66\x67\x68\x69\x6A\x6B\x6C\x6D\x6E\x6F\
+            \\x70\x71\x72\x73\x74\x75\x76\x77\x78\x79\x7A\x7B\x7C\x7D\x7E\x7F\
+            \\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8A\x8B\x8C\x8D\x8E\x8F\
+            \\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9A\x9B\x9C\x9D\x9E\x9F\
+            \\xA0\xA1\xA2\xA3\xA4\xA5\xA6\xA7\xA8\xA9\xAA\xAB\xAC\xAD\xAE\xAF\
+            \\xB0\xB1\xB2\xB3\xB4\xB5\xB6\xB7\xB8\xB9\xBA\xBB\xBC\xBD\xBE\xBF\
+            \\xC0\xC1\xC2\xC3\xC4\xC5\xC6\xC7\xC8\xC9\xCA\xCB\xCC\xCD\xCE\xCF\
+            \\xD0\xD1\xD2\xD3\xD4\xD5\xD6\xD7\xD8\xD9\xDA\xDB\xDC\xDD\xDE\xDF\
+            \\xE0\xE1\xE2\xE3\xE4\xE5\xE6\xE7\xE8\xE9\xEA\xEB\xEC\xED\xEE\xEF\
+            \\xF0\xF1\xF2\xF3\xF4\xF5\xF6\xF7\xF8\xF9\xFA\xFB\xFC\xFD\xFE\xFF"
+            ||]
+        )
+
+test_CompileBuiltinByteStringLiteral_StringToBuiltinByteString :: TestTree
+test_CompileBuiltinByteStringLiteral_StringToBuiltinByteString =
+  testCase "stringToBuiltinByteString" do
+    display (_progTerm (getPlcNoAnn compiledLiteral)) @?= expectedUplc
+  where
+    compiledLiteral :: CompiledCode BuiltinByteString =
+      $$( compile
+            [||
+            stringToBuiltinByteString
+              "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F\
+              \\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1A\x1B\x1C\x1D\x1E\x1F\
+              \\x20\x21\x22\x23\x24\x25\x26\x27\x28\x29\x2A\x2B\x2C\x2D\x2E\x2F\
+              \\x30\x31\x32\x33\x34\x35\x36\x37\x38\x39\x3A\x3B\x3C\x3D\x3E\x3F\
+              \\x40\x41\x42\x43\x44\x45\x46\x47\x48\x49\x4A\x4B\x4C\x4D\x4E\x4F\
+              \\x50\x51\x52\x53\x54\x55\x56\x57\x58\x59\x5A\x5B\x5C\x5D\x5E\x5F\
+              \\x60\x61\x62\x63\x64\x65\x66\x67\x68\x69\x6A\x6B\x6C\x6D\x6E\x6F\
+              \\x70\x71\x72\x73\x74\x75\x76\x77\x78\x79\x7A\x7B\x7C\x7D\x7E\x7F\
+              \\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8A\x8B\x8C\x8D\x8E\x8F\
+              \\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9A\x9B\x9C\x9D\x9E\x9F\
+              \\xA0\xA1\xA2\xA3\xA4\xA5\xA6\xA7\xA8\xA9\xAA\xAB\xAC\xAD\xAE\xAF\
+              \\xB0\xB1\xB2\xB3\xB4\xB5\xB6\xB7\xB8\xB9\xBA\xBB\xBC\xBD\xBE\xBF\
+              \\xC0\xC1\xC2\xC3\xC4\xC5\xC6\xC7\xC8\xC9\xCA\xCB\xCC\xCD\xCE\xCF\
+              \\xD0\xD1\xD2\xD3\xD4\xD5\xD6\xD7\xD8\xD9\xDA\xDB\xDC\xDD\xDE\xDF\
+              \\xE0\xE1\xE2\xE3\xE4\xE5\xE6\xE7\xE8\xE9\xEA\xEB\xEC\xED\xEE\xEF\
+              \\xF0\xF1\xF2\xF3\xF4\xF5\xF6\xF7\xF8\xF9\xFA\xFB\xFC\xFD\xFE\xFF"
+            ||]
+        )
+
+expectedUplc :: String
+expectedUplc =
+  "(con\n  bytestring\n  #\
+  \000102030405060708090a0b0c0d0e0f\
+  \101112131415161718191a1b1c1d1e1f\
+  \202122232425262728292a2b2c2d2e2f\
+  \303132333435363738393a3b3c3d3e3f\
+  \404142434445464748494a4b4c4d4e4f\
+  \505152535455565758595a5b5c5d5e5f\
+  \606162636465666768696a6b6c6d6e6f\
+  \707172737475767778797a7b7c7d7e7f\
+  \808182838485868788898a8b8c8d8e8f\
+  \909192939495969798999a9b9c9d9e9f\
+  \a0a1a2a3a4a5a6a7a8a9aaabacadaeaf\
+  \b0b1b2b3b4b5b6b7b8b9babbbcbdbebf\
+  \c0c1c2c3c4c5c6c7c8c9cacbcccdcecf\
+  \d0d1d2d3d4d5d6d7d8d9dadbdcdddedf\
+  \e0e1e2e3e4e5e6e7e8e9eaebecedeeef\
+  \f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff\
+  \\n)"
diff --git a/plutus-tx-plugin/test/Spec.hs b/plutus-tx-plugin/test/Spec.hs
index 6e7e74d74b6..9a9b63dd44b 100644
--- a/plutus-tx-plugin/test/Spec.hs
+++ b/plutus-tx-plugin/test/Spec.hs
@@ -4,6 +4,7 @@ import AsData.Budget.Spec qualified as AsData.Budget
 import AssocMap.Spec qualified as AssocMap
 import Blueprint.Tests qualified
 import Budget.Spec qualified as Budget
+import ByteStringLiterals.Spec qualified as ByteStringLiterals
 import IntegerLiterals.NoStrict.NegativeLiterals.Spec qualified
 import IntegerLiterals.NoStrict.NoNegativeLiterals.Spec qualified
 import IntegerLiterals.Strict.NegativeLiterals.Spec qualified
@@ -25,12 +26,14 @@ main = defaultMain tests
 
 tests :: TestTree
 tests =
-  runTestNested ["test"]
+  runTestNested
+    ["test"]
     [ Plugin.tests
     , IntegerLiterals.NoStrict.NegativeLiterals.Spec.tests
     , IntegerLiterals.NoStrict.NoNegativeLiterals.Spec.tests
     , IntegerLiterals.Strict.NegativeLiterals.Spec.tests
     , IntegerLiterals.Strict.NoNegativeLiterals.Spec.tests
+    , embed ByteStringLiterals.tests
     , IsData.tests
     , Lift.tests
     , TH.tests
diff --git a/plutus-tx/src/PlutusTx/Builtins/HasOpaque.hs b/plutus-tx/src/PlutusTx/Builtins/HasOpaque.hs
index ed784740a52..3ce21e91bad 100644
--- a/plutus-tx/src/PlutusTx/Builtins/HasOpaque.hs
+++ b/plutus-tx/src/PlutusTx/Builtins/HasOpaque.hs
@@ -13,7 +13,7 @@
 
 module PlutusTx.Builtins.HasOpaque where
 
-import PlutusTx.Base (id, ($))
+import PlutusTx.Base (id)
 import PlutusTx.Bool (Bool (..))
 import PlutusTx.Builtins.Internal
 
@@ -43,7 +43,7 @@ an unfolding.
 -}
 
 stringToBuiltinByteString :: Haskell.String -> BuiltinByteString
-stringToBuiltinByteString str = encodeUtf8 $ stringToBuiltinString str
+stringToBuiltinByteString str = BuiltinByteString (fromString str)
 {-# OPAQUE stringToBuiltinByteString #-}
 
 stringToBuiltinString :: Haskell.String -> BuiltinString
@@ -226,7 +226,7 @@ instance HasToOpaque (BuiltinData, BuiltinData) (BuiltinPair BuiltinData Builtin
     {-# INLINABLE toOpaque #-}
 instance (HasFromOpaque arep a, HasFromOpaque brep b) =>
         HasFromOpaque (BuiltinPair arep brep) (a, b) where
-    fromOpaque p = (fromOpaque $ fst p, fromOpaque $ snd p)
+    fromOpaque p = (fromOpaque (fst p), fromOpaque (snd p))
     {-# INLINABLE fromOpaque #-}
 
 instance HasToOpaque BuiltinData BuiltinData