diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 4810a32..b7a27b5 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -1,13 +1,12 @@
 [versions]
-agp = "8.2.0"
+agp = "8.2.2"
 android-compileSdk = "34"
 android-minSdk = "26"
 android-targetSdk = "34"
-androidx-activityCompose = "1.8.2"
-composeCompiler = "1.5.12"
+androidx-activityCompose = "1.9.0"
 composeBom = "2024.04.01"
+composeCompiler = "1.5.12"
 coroutines = "1.8.0"
-cryptography = "0.3.0"
 kotlin = "1.9.23"
 ktor = "2.3.9"
 multiplatform-settings = "1.1.1"
@@ -25,7 +24,6 @@ compose-ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-mani
 compose-ui-tooling = { group = "androidx.compose.ui", name = "ui-tooling" }
 compose-ui-tooling-preview = { group = "androidx.compose.ui", name = "ui-tooling-preview" }
 coroutines-core = { group = "org.jetbrains.kotlinx", name = "kotlinx-coroutines-core", version.ref = "coroutines" }
-cryptography-bigint = { group = "dev.whyoleg.cryptography", name = "cryptography-bigint", version.ref = "cryptography" }
 kotlin-test = { group = "org.jetbrains.kotlin", name = "kotlin-test", version.ref = "kotlin" }
 ktor-client-cio = { group = "io.ktor", name = "ktor-client-cio", version.ref = "ktor" }
 ktor-client-core = { group = "io.ktor", name = "ktor-client-core", version.ref = "ktor" }
diff --git a/library/crypto/build.gradle.kts b/library/crypto/build.gradle.kts
index e199814..a0e08fe 100644
--- a/library/crypto/build.gradle.kts
+++ b/library/crypto/build.gradle.kts
@@ -3,7 +3,5 @@ plugins {
 }
 
 dependencies {
-    implementation(libs.cryptography.bigint)
-
     testImplementation(libs.kotlin.test)
 }
diff --git a/library/crypto/src/main/kotlin/net/agorise/shared/crypto/BigIntegerKtx.kt b/library/crypto/src/main/kotlin/net/agorise/shared/crypto/BigIntegerKtx.kt
new file mode 100644
index 0000000..6d1de13
--- /dev/null
+++ b/library/crypto/src/main/kotlin/net/agorise/shared/crypto/BigIntegerKtx.kt
@@ -0,0 +1,11 @@
+package net.agorise.shared.crypto
+
+import java.math.BigInteger
+
+@OptIn(ExperimentalStdlibApi::class)
+fun BigInteger.toHexString(format: HexFormat = HexFormat.Default): String =
+    toByteArray().toHexString(format)
+
+@OptIn(ExperimentalStdlibApi::class)
+fun String.hexToBigInteger(format: HexFormat = HexFormat.Default): BigInteger =
+    BigInteger(hexToByteArray(format))
diff --git a/library/stargate/build.gradle.kts b/library/stargate/build.gradle.kts
index 103b826..c3576b9 100644
--- a/library/stargate/build.gradle.kts
+++ b/library/stargate/build.gradle.kts
@@ -6,7 +6,6 @@ dependencies {
     implementation(projects.library.crypto)
 
     implementation(libs.coroutines.core)
-    implementation(libs.cryptography.bigint)
     implementation(libs.ktor.client.cio)
     implementation(libs.ktor.client.core)
     implementation(libs.ktor.client.websockets)
diff --git a/library/stargate/src/main/kotlin/net/agorise/shared/stargate/mnemonics/Mnemonics.kt b/library/stargate/src/main/kotlin/net/agorise/shared/stargate/mnemonics/Mnemonics.kt
index 4ed891c..20f16ea 100644
--- a/library/stargate/src/main/kotlin/net/agorise/shared/stargate/mnemonics/Mnemonics.kt
+++ b/library/stargate/src/main/kotlin/net/agorise/shared/stargate/mnemonics/Mnemonics.kt
@@ -1,9 +1,8 @@
 package net.agorise.shared.stargate.mnemonics
 
-import dev.whyoleg.cryptography.bigint.BigInt
-import dev.whyoleg.cryptography.bigint.decodeToBigInt
 import io.ktor.utils.io.core.toByteArray
 import net.agorise.shared.crypto.Crc32
+import java.math.BigInteger
 
 /**
  * Provides functionality to create and validate mnemonics.
@@ -40,7 +39,7 @@ class Mnemonics {
     /**
      * Given a list of words, returns the associated key if the words are valid or an exception otherwise
      */
-    fun getKeyAndLanguageFromWords(words: List<String>): Result<Pair<BigInt, String>> {
+    fun getKeyAndLanguageFromWords(words: List<String>): Result<Pair<BigInteger, String>> {
         // The list must contain SEED_LENGTH + 1 words. The SEED_LENGTH + 1 word is the checksum
         if (words.size != (SEED_LENGTH + 1)) {
             return Result.failure(Exception("Invalid seed"))
@@ -79,7 +78,7 @@ class Mnemonics {
 
         val languageName = languages[languageIndex].name
 
-        return Result.success(Pair(key.decodeToBigInt(), languageName))
+        return Result.success(Pair(BigInteger(key), languageName))
     }
 
     /**
diff --git a/library/stargate/src/test/kotlin/net/agorise/shared/stargate/mnemonics/MnemonicsTest.kt b/library/stargate/src/test/kotlin/net/agorise/shared/stargate/mnemonics/MnemonicsTest.kt
index 0670c0c..a65f105 100644
--- a/library/stargate/src/test/kotlin/net/agorise/shared/stargate/mnemonics/MnemonicsTest.kt
+++ b/library/stargate/src/test/kotlin/net/agorise/shared/stargate/mnemonics/MnemonicsTest.kt
@@ -1,10 +1,10 @@
 package net.agorise.shared.stargate.mnemonics
 
-import dev.whyoleg.cryptography.bigint.toHexString
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
 import kotlin.test.assertTrue
+import net.agorise.shared.crypto.toHexString
 
 class MnemonicsTest {
     private val mnemonics = Mnemonics()