diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 0c5d0b8eb0..ef276532fb 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -28,7 +28,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        scala-version: [213, 3]
+        scala-version: [212, 213, 3]
         postgres-version: [12, 16]
     steps:
       - uses: actions/checkout@v4
@@ -49,6 +49,20 @@ jobs:
           bleep compile jvm${{ matrix.scala-version }}
           bleep test jvm${{ matrix.scala-version }}
 
+  build-scala212:
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+    if: "!contains(github.event.head_commit.message, 'ci skip')"
+    steps:
+      - uses: actions/checkout@v4
+      - uses: bleep-build/bleep-setup-action@0.0.1
+      - uses: coursier/cache-action@v6
+        with:
+          extraFiles: bleep.yaml
+
+      - name: Compile for 2.12
+        run: bleep compile typo@jvm212
+
   build-docs:
     timeout-minutes: 20
     runs-on: ubuntu-latest
diff --git a/bleep.yaml b/bleep.yaml
index a7b29719d7..918af0ae1d 100644
--- a/bleep.yaml
+++ b/bleep.yaml
@@ -11,6 +11,12 @@ projects:
     isTestProject: true
   # main project
   typo:
+    cross:
+      jvm212:
+        scala:
+          strict: false
+          options: -Xsource:3 -language:higherKinds -language:implicitConversions
+          version: 2.12.19
     dependencies:
     - com.typesafe.play::play-json:2.10.6
     - org.playframework.anorm::anorm:2.7.0
diff --git a/typo/src/scala/typo/ProjectGraph.scala b/typo/src/scala/typo/ProjectGraph.scala
index 44725411a4..90f3fea959 100644
--- a/typo/src/scala/typo/ProjectGraph.scala
+++ b/typo/src/scala/typo/ProjectGraph.scala
@@ -1,5 +1,7 @@
 package typo
 
+import typo.internal.compat.*
+
 import java.nio.file.Path
 import scala.concurrent.{ExecutionContext, Future}
 
@@ -11,7 +13,7 @@ import scala.concurrent.{ExecutionContext, Future}
   */
 final case class ProjectGraph[T, S](name: String, target: Path, testTarget: Option[Path], value: T, scripts: S, downstream: List[ProjectGraph[T, S]]) {
   def toList: List[ProjectGraph[T, S]] =
-    (this :: downstream.flatMap(_.toList)).distinctBy(_.target)
+    (this :: downstream.flatMap(_.toList)).distinctByCompat(_.target)
 
   def valueFromProject[TT, SS](f: ProjectGraph[T, S] => (TT, SS)): ProjectGraph[TT, SS] = {
     val (tt, ss) = f(this)
diff --git a/typo/src/scala/typo/internal/ComputedTestInserts.scala b/typo/src/scala/typo/internal/ComputedTestInserts.scala
index 435130383a..2372a3125c 100644
--- a/typo/src/scala/typo/internal/ComputedTestInserts.scala
+++ b/typo/src/scala/typo/internal/ComputedTestInserts.scala
@@ -3,6 +3,7 @@ package internal
 
 import typo.db.Type
 import typo.internal.codegen.*
+import typo.internal.compat.*
 
 case class ComputedTestInserts(tpe: sc.Type.Qualified, methods: List[ComputedTestInserts.InsertMethod], maybeDomainMethods: Option[ComputedTestInserts.GenerateDomainMethods])
 
@@ -223,7 +224,7 @@ object ComputedTestInserts {
         }
       } yield GenerateDomainMethod(domain)
 
-      NonEmptyList.fromList(all.toList.distinctBy(_.dom.tpe).sortBy(_.dom.tpe))
+      NonEmptyList.fromList(all.toList.distinctByCompat(_.dom.tpe).sortBy(_.dom.tpe))
     }
   }
 }
diff --git a/typo/src/scala/typo/internal/FkAnalysis.scala b/typo/src/scala/typo/internal/FkAnalysis.scala
index 7ef9ad00ad..be061be655 100644
--- a/typo/src/scala/typo/internal/FkAnalysis.scala
+++ b/typo/src/scala/typo/internal/FkAnalysis.scala
@@ -2,6 +2,7 @@ package typo
 package internal
 
 import typo.internal.codegen.*
+import typo.internal.compat.*
 
 class FkAnalysis(table: ComputedTable, candidateFks: List[FkAnalysis.CandidateFk]) {
   lazy val createWithFkIdsRow: Option[FkAnalysis.CreateWithFkIds] =
@@ -44,7 +45,8 @@ object FkAnalysis {
     lazy val exprsForColumn: Map[sc.Ident, List[sc.Code]] =
       byFks.toList
         .flatMap(colsFromFk => colsFromFk.colPairs.map { case (_, col) => (col.name, colsFromFk.expr(col.name)) })
-        .groupMap { case (colName, _) => colName } { case (_, expr) => expr }
+        .groupBy { case (colName, _) => colName }
+        .map { case (k, tuples) => (k, tuples.map { case (_, expr) => expr }) }
 
     /** reduce the potentially multiple values in [[exprsForColumn]] down to one expression, with `require` to assert that the others contain the same value */
     lazy val exprForColumn: Map[sc.Ident, sc.Code] =
@@ -164,7 +166,7 @@ object FkAnalysis {
         .toList
         // consider longest first, plus disambiguate for consistency
         .sortBy(x => (-x.colPairs.length, x.name))
-        .distinctBy(_.name)
+        .distinctByCompat(_.name)
   }
 
   case class CandidateFk(thisFk: db.ForeignKey, otherTable: ComputedTable, otherId: IdComputed.Composite)
diff --git a/typo/src/scala/typo/internal/IdComputed.scala b/typo/src/scala/typo/internal/IdComputed.scala
index 186eccabca..fa9744a01a 100644
--- a/typo/src/scala/typo/internal/IdComputed.scala
+++ b/typo/src/scala/typo/internal/IdComputed.scala
@@ -1,6 +1,8 @@
 package typo
 package internal
 
+import typo.internal.compat.*
+
 sealed trait IdComputed {
   def paramName: sc.Ident
   def cols: NonEmptyList[ComputedColumn]
@@ -8,7 +10,7 @@ sealed trait IdComputed {
   final def param: sc.Param = sc.Param(paramName, tpe, None)
 
   final lazy val userDefinedColTypes: List[sc.Type] =
-    cols.toList.collect { case x if sc.Type.containsUserDefined(x.tpe) => x }.map(_.tpe).distinctBy(sc.Type.base)
+    cols.toList.collect { case x if sc.Type.containsUserDefined(x.tpe) => x }.map(_.tpe).distinctByCompat(sc.Type.base)
 }
 
 object IdComputed {
diff --git a/typo/src/scala/typo/internal/analysis/DecomposedSql.scala b/typo/src/scala/typo/internal/analysis/DecomposedSql.scala
index 10067376cb..853ea083e0 100644
--- a/typo/src/scala/typo/internal/analysis/DecomposedSql.scala
+++ b/typo/src/scala/typo/internal/analysis/DecomposedSql.scala
@@ -1,6 +1,7 @@
 package typo.internal.analysis
 
 import typo.internal.codegen.CodeOps
+import typo.internal.compat.*
 import typo.{db, sc}
 
 case class DecomposedSql(frags: List[DecomposedSql.Fragment]) {
@@ -42,7 +43,7 @@ case class DecomposedSql(frags: List[DecomposedSql.Fragment]) {
       paramsWithIndex.collect { case (DecomposedSql.NamedParam(parsedName), i) if parsedName.name == name => i }
 
     paramsWithIndex
-      .distinctBy {
+      .distinctByCompat {
         case (DecomposedSql.NotNamedParam, idx)        => idx.toString
         case (DecomposedSql.NamedParam(parsedName), _) => parsedName.name
       }
diff --git a/typo/src/scala/typo/internal/codegen/FilesRelation.scala b/typo/src/scala/typo/internal/codegen/FilesRelation.scala
index 55e571ae4d..df3ca11350 100644
--- a/typo/src/scala/typo/internal/codegen/FilesRelation.scala
+++ b/typo/src/scala/typo/internal/codegen/FilesRelation.scala
@@ -3,6 +3,7 @@ package internal
 package codegen
 
 import play.api.libs.json.Json
+import typo.internal.compat.*
 
 case class FilesRelation(
     naming: Naming,
@@ -33,7 +34,7 @@ case class FilesRelation(
                      |  ${args.mkCode(",\n")}
                      |)""".stripMargin
 
-          sc.Value(Nil, extractFkId.name.prepended("extract"), Nil, Nil, extractFkId.otherCompositeIdType, body)
+          sc.Value(Nil, extractFkId.name.prepended("extract"), Nil, Nil, extractFkId.otherCompositeIdType, body).code
         },
         maybeUnsavedRow.map { case (unsaved, defaults) =>
           val (partOfId, rest) = unsaved.defaultCols.toList.partition { case (col, _) => names.isIdColumn(col.dbName) }
@@ -182,7 +183,7 @@ case class FilesRelation(
                        |    ${columnPairs.mkCode("\n")}""".stripMargin
                 (fkName, body)
               }
-              .distinctBy(_._1)
+              .distinctByCompat(_._1)
               .map(_._2)
           case Source.SqlFile(_) => Nil
         }
diff --git a/typo/src/scala/typo/internal/compat.scala b/typo/src/scala/typo/internal/compat.scala
new file mode 100644
index 0000000000..a02e4e3599
--- /dev/null
+++ b/typo/src/scala/typo/internal/compat.scala
@@ -0,0 +1,23 @@
+package typo.internal
+
+import scala.collection.mutable
+
+object compat {
+  // compat with scala 2.12
+  implicit class ListOps[A](as: List[A]) {
+    def distinctByCompat[B, C](f: A => B): List[A] = {
+      if (as.lengthCompare(1) <= 0) as
+      else {
+        val builder = List.newBuilder[A]
+        val seen = mutable.HashSet.empty[B]
+        val it = as.iterator
+        var different = false
+        while (it.hasNext) {
+          val next = it.next()
+          if (seen.add(f(next))) builder += next else different = true
+        }
+        if (different) builder.result() else as
+      }
+    }
+  }
+}
diff --git a/typo/src/scala/typo/internal/findTypeFromFk.scala b/typo/src/scala/typo/internal/findTypeFromFk.scala
index 0184fa31b2..fc13bf5ab7 100644
--- a/typo/src/scala/typo/internal/findTypeFromFk.scala
+++ b/typo/src/scala/typo/internal/findTypeFromFk.scala
@@ -2,6 +2,7 @@ package typo
 package internal
 
 import typo.internal.rewriteDependentData.EvalMaybe
+import typo.internal.compat.*
 
 // we let types flow through constraints down to this column, the point is to reuse id types downstream
 object findTypeFromFk {
@@ -25,7 +26,7 @@ object findTypeFromFk {
           } yield Right(otherCol.tpe)
       }
 
-    all.distinctBy { e => sc.Type.base(e.merge) } match {
+    all.distinctByCompat { e => sc.Type.base(e.merge) } match {
       case Nil      => None
       case e :: Nil => Some(e.merge)
       case all =>
diff --git a/typo/src/scala/typo/internal/forget.scala b/typo/src/scala/typo/internal/forget.scala
new file mode 100644
index 0000000000..7fffdc32a8
--- /dev/null
+++ b/typo/src/scala/typo/internal/forget.scala
@@ -0,0 +1,5 @@
+package typo.internal
+
+object forget {
+  def apply[T](t: T): Unit = (t, ())._2
+}
diff --git a/typo/src/scala/typo/internal/generate.scala b/typo/src/scala/typo/internal/generate.scala
index 7bdcabac6e..24648dbc89 100644
--- a/typo/src/scala/typo/internal/generate.scala
+++ b/typo/src/scala/typo/internal/generate.scala
@@ -4,7 +4,6 @@ package internal
 import typo.internal.codegen.*
 import typo.internal.sqlfiles.SqlFile
 
-import scala.annotation.nowarn
 import scala.collection.immutable
 import scala.collection.immutable.SortedMap
 
@@ -77,8 +76,7 @@ object generate {
 
         computedLazyRelations.foreach { case (relName, lazyValue) =>
           if (selector.include(relName)) {
-            lazyValue.get: @nowarn
-            ()
+            forget(lazyValue.get)
           }
         }
 
diff --git a/typo/src/scala/typo/internal/quote.scala b/typo/src/scala/typo/internal/quote.scala
index 2e5a65a8da..8ec7b90347 100644
--- a/typo/src/scala/typo/internal/quote.scala
+++ b/typo/src/scala/typo/internal/quote.scala
@@ -1,6 +1,8 @@
 package typo.internal
 
 object quote {
-  def apply(str: String) = s"'$str'"
-  def double(str: String) = s"\"$str\""
+  val Quote = '\''
+  val DoubleQuote = '"'
+  def apply(str: String) = s"$Quote${str}$Quote"
+  def double(str: String) = s"$DoubleQuote${str}$DoubleQuote"
 }