diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 288ceea..d771f6f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -7,10 +7,10 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        nim: [1.6.14]
+        nim: [stable, 1.6.20]
     steps:
     - uses: actions/checkout@v2
-    - uses: iffy/install-nim@v3
+    - uses: iffy/install-nim@v5
       with:
         version: ${{ matrix.nim }}
     - name: Build
diff --git a/poseidon2.nim b/poseidon2.nim
index 694f12b..6fd7229 100644
--- a/poseidon2.nim
+++ b/poseidon2.nim
@@ -15,6 +15,6 @@ export toF
 export elements
 export types
 
-# workaround for "undeclared identifier: 'getCurveOrder'"
-import constantine/math/config/curves
-export curves
+# workaround for "undeclared identifier: 'getModulus'"
+import constantine/named/algebras
+export algebras
diff --git a/poseidon2.nimble b/poseidon2.nimble
index 131eac7..4e3f4b8 100644
--- a/poseidon2.nimble
+++ b/poseidon2.nimble
@@ -3,4 +3,4 @@ author = "nim-poseidon2 authors"
 description = "Poseidon2 hash function"
 license = "MIT"
 
-requires "https://github.com/mratsim/constantine#ab6fa6ae1bbbd1b10071a92ec209b381b5d82511"
+requires "https://github.com/mratsim/constantine == 0.1.0"
diff --git a/poseidon2/io.nim b/poseidon2/io.nim
index 68d7157..4ca3f30 100644
--- a/poseidon2/io.nim
+++ b/poseidon2/io.nim
@@ -2,10 +2,10 @@ import std/options
 import constantine/math/arithmetic
 import constantine/math/io/io_bigints
 import constantine/math/io/io_fields
-import constantine/math/config/curves
+import constantine/named/algebras
 import ./types
 
-export curves
+export algebras
 
 func fromOpenArray(_: type F, bytes: openArray[byte]): F =
   F.fromBig(B.unmarshal(bytes, littleEndian))
@@ -19,7 +19,7 @@ func fromBytes*(_: type F, bytes: array[32, byte]): Option[F] =
   ## Converts bytes into a field element. The byte array is interpreted as a
   ## canonical little-endian big integer.
   let big = B.unmarshal(bytes, littleEndian)
-  if bool(big < F.fieldMod()):
+  if bool(big < F.getModulus()):
     return some(F.fromBig(big))
 
 func toBytes*(element: F): array[32, byte] =
diff --git a/poseidon2/roundfun.nim b/poseidon2/roundfun.nim
index 7e9d5a0..dc087aa 100644
--- a/poseidon2/roundfun.nim
+++ b/poseidon2/roundfun.nim
@@ -1,6 +1,6 @@
 import
   constantine/math/arithmetic,
-  constantine/math/config/curves
+  constantine/named/algebras
 
 import ./types
 import ./roundconst
diff --git a/poseidon2/types.nim b/poseidon2/types.nim
index 2c9fa52..4920ec9 100644
--- a/poseidon2/types.nim
+++ b/poseidon2/types.nim
@@ -3,7 +3,7 @@ import
   constantine/math/arithmetic,
   constantine/math/io/io_fields,
   constantine/math/io/io_bigints,
-  constantine/math/config/curves
+  constantine/named/algebras
 
 #-------------------------------------------------------------------------------
 
diff --git a/tests/poseidon2/testSponge.nim b/tests/poseidon2/testSponge.nim
index edd931a..44f0558 100644
--- a/tests/poseidon2/testSponge.nim
+++ b/tests/poseidon2/testSponge.nim
@@ -2,7 +2,6 @@ import std/unittest
 import std/sequtils
 
 import constantine/math/io/io_fields
-import constantine/math/arithmetic
 
 import poseidon2/types
 import poseidon2/io