diff --git a/build.gradle.kts b/build.gradle.kts
index f66ba3c..f88218d 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -45,7 +45,7 @@ plugins {
     idea
     kotlin("jvm") version "1.9.0"
     id("org.jetbrains.intellij") version "1.15.0"
-    id("org.jetbrains.grammarkit") version "2022.3.1"
+    id("org.jetbrains.grammarkit") version "2021.2.2"
 }
 
 allprojects {
@@ -176,7 +176,7 @@ project(":") {
     }
 
     val generateRegoLexer = task<GenerateLexerTask>("generateRegoLexer") {
-        sourceFile.set(file("src/main/grammar/RegoLexer.flex"))
+        source.set("src/main/grammar/RegoLexer.flex")
         targetDir.set("src/main/gen/org/openpolicyagent/ideaplugin/lang/lexer")
         targetClass.set("_RegoLexer")
         purgeOldFiles.set(true)
@@ -184,7 +184,7 @@ project(":") {
 
 
     val generateRegoParser = task<GenerateParserTask>("generateRegoParser") {
-        sourceFile.set(file("src/main/grammar/Rego.bnf"))
+        source.set("src/main/grammar/Rego.bnf")
         targetRoot.set("src/main/gen")
         pathToParser.set("/org/openpolicyagent/ideaplugin/lang/parser/RegoParser.java")
         pathToPsiRoot.set("/org/openpolicyagent/ideaplugin/lang/psi")
diff --git a/gradle.properties b/gradle.properties
index 1f4bc2d..38f2328 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -9,13 +9,13 @@ kotlin.code.style=official
 baseIDE=idea
 
 # if you change the version of ide, also change psiViewerPluginVersion accordingly (cf https://plugins.jetbrains.com/plugin/227-psiviewer/versions)
-ideaVersion=IC-2023.2
-pycharmCommunityVersion=PC-2023.2
-psiViewerPluginVersion=232.2
+ideaVersion=IC-2023.1
+pycharmCommunityVersion=PC-2023.1
+psiViewerPluginVersion=231-SNAPSHOT
 
 # see https://www.jetbrains.org/intellij/sdk/docs/basics/getting_started/build_number_ranges.html for more information
-sinceBuild=232
-untilBuild=233.*
+sinceBuild=231
+untilBuild=232.*
 
 # these two variables will be overwritten by the release process (i.e. the GitHub action) thanks to the env variables:
 #   - ORG_GRADLE_PROJECT_publishToken