diff --git a/build/build.sh b/build/build.sh
index 558ff3cea2..fccd7b5ad6 100755
--- a/build/build.sh
+++ b/build/build.sh
@@ -23,7 +23,7 @@ export CASSANDRA_DC=datacenter1
 export ORIENTDB_HOST=127.0.0.1
 export ORIENTDB_PORT=12424
 
-export JVM_OPTS="-Dquill.macro.log=false -Dquill.scala.version=$SCALA_VERSION -Xms1024m -Xmx3g -Xss5m -XX:ReservedCodeCacheSize=256m -XX:+TieredCompilation -XX:+CMSClassUnloadingEnabled -XX:+UseConcMarkSweepGC"
+export JVM_OPTS="-Dquill.macro.log=false -Dquill.quat.strict=true -Dquill.scala.version=$SCALA_VERSION -Xms1024m -Xmx3g -Xss5m -XX:ReservedCodeCacheSize=256m -XX:+TieredCompilation -XX:+CMSClassUnloadingEnabled -XX:+UseConcMarkSweepGC"
 
 modules=$1
 echo "Start build modules: $modules"
diff --git a/quill-core/src/main/scala/io/getquill/quotation/Parsing.scala b/quill-core/src/main/scala/io/getquill/quotation/Parsing.scala
index 351a68230b..16dd2277a0 100644
--- a/quill-core/src/main/scala/io/getquill/quotation/Parsing.scala
+++ b/quill-core/src/main/scala/io/getquill/quotation/Parsing.scala
@@ -320,17 +320,17 @@ trait Parsing extends ValueComputation with QuatMaking {
 
   val infixParser: Parser[Ast] = Parser[Ast] {
     case q"$infix.pure.asCondition" =>
-      combinedInfixParser(true, Quat.BooleanExpression)(infix)
+      Quat.improveInfixQuat(combinedInfixParser(true, Quat.BooleanExpression)(infix))
     case q"$infix.asCondition" =>
-      combinedInfixParser(false, Quat.BooleanExpression)(infix)
+      Quat.improveInfixQuat(combinedInfixParser(false, Quat.BooleanExpression)(infix))
     case q"$infix.generic.pure.as[$t]" =>
-      combinedInfixParser(true, Quat.Generic)(infix)
+      Quat.improveInfixQuat(combinedInfixParser(true, Quat.Generic)(infix))
     case q"$infix.pure.as[$t]" =>
-      combinedInfixParser(true, inferQuat(q"$t".tpe))(infix)
+      Quat.improveInfixQuat(combinedInfixParser(true, inferQuat(q"$t".tpe))(infix))
     case q"$infix.as[$t]" =>
-      combinedInfixParser(false, inferQuat(q"$t".tpe))(infix)
+      Quat.improveInfixQuat(combinedInfixParser(false, inferQuat(q"$t".tpe))(infix))
     case `impureInfixParser`(value) =>
-      value
+      Quat.improveInfixQuat(value)
   }
 
   val impureInfixParser = combinedInfixParser(false, Quat.Value) // TODO Verify Quat in what cases does this come up?
diff --git a/quill-core/src/test/scala/io/getquill/quat/QuatSpec.scala b/quill-core/src/test/scala/io/getquill/quat/QuatSpec.scala
index 169c1b4c42..7141626df3 100644
--- a/quill-core/src/test/scala/io/getquill/quat/QuatSpec.scala
+++ b/quill-core/src/test/scala/io/getquill/quat/QuatSpec.scala
@@ -1,7 +1,9 @@
 package io.getquill.quat
 
 import io.getquill._
+import io.getquill.norm.RepropagateQuats
 import io.getquill.quotation.QuatException
+
 import scala.language.reflectiveCalls
 
 class QuatSpec extends Spec {
@@ -30,6 +32,40 @@ class QuatSpec extends Spec {
     quote(query[MyPerson]).ast.quat mustEqual MyPersonQuat
   }
 
+  "should refine quats from generic infixes" - {
+    case class MyPerson(name: String, age: Int)
+    val MyPersonQuat = Quat.Product("name" -> Quat.Value, "age" -> Quat.Value)
+
+    "from extension methods" in {
+      implicit class QueryOps[Q <: Query[_]](q: Q) {
+        def appendFoo = quote(infix"$q APPEND FOO".pure.as[Q])
+      }
+      val q = quote(query[MyPerson].appendFoo)
+      q.ast.quat mustEqual MyPersonQuat // I.e ReifyLiftings runs RepropagateQuats to take care of this
+    }
+
+    "from extension methods - generic marker" in {
+      implicit class QueryOps[Q <: Query[_]](q: Q) {
+        def appendFoo = quote(infix"$q APPEND FOO".generic.pure.as[Q])
+      }
+      val q = quote(query[MyPerson].appendFoo)
+      q.ast.quat mustEqual MyPersonQuat // I.e ReifyLiftings runs RepropagateQuats to take care of this
+    }
+
+    "should support query-ops function" in {
+      def appendFooFun[Q <: Query[_]] = quote { (q: Q) => infix"$q APPEND FOO".pure.as[Q] }
+      val q = quote(appendFooFun(query[MyPerson]))
+      q.ast.quat mustEqual MyPersonQuat
+    }
+
+    "should support query-ops function - dynamic function" in {
+      def appendFooFun[Q <: Query[_]]: Quoted[Q => Q] = quote { (q: Q) => infix"$q APPEND FOO".pure.as[Q] }
+      val q = quote(appendFooFun(query[MyPerson]))
+      q.ast.quat mustEqual Quat.Unknown
+      println(io.getquill.util.Messages.qprint(testContext.run(q)))
+    }
+  }
+
   "should support multi-level embedded" in {
     case class MyName(first: String, last: String) extends Embedded
     case class MyId(name: MyName, memberNum: Int) extends Embedded
diff --git a/quill-engine/src/main/scala/io/getquill/AstPrinter.scala b/quill-engine/src/main/scala/io/getquill/AstPrinter.scala
index 7541f62b44..62b1ea72b5 100644
--- a/quill-engine/src/main/scala/io/getquill/AstPrinter.scala
+++ b/quill-engine/src/main/scala/io/getquill/AstPrinter.scala
@@ -53,6 +53,7 @@ class AstPrinter(traceOpinions: Boolean, traceAstSimple: Boolean, traceQuats: Qu
       }
     def withQuat(q: Quat): treemake = toContent.andWith(treemake.Quat(q))
     def withTree(t: pprint.Tree): treemake = toContent.andWith(treemake.Tree(t))
+    def withElem(a: Any): treemake = toContent.andWith(treemake.Elem(a))
     private def treeifyList: List[Tree] =
       toContent.list.flatMap {
         case e: treemake.Quat =>
@@ -61,11 +62,11 @@ class AstPrinter(traceOpinions: Boolean, traceAstSimple: Boolean, traceQuats: Qu
             case QuatTrace.Short                => List(Tree.Literal(e.q.shortString.take(10)))
             case QuatTrace.None                 => List()
           }
-        case treemake.Elem(value)   => List(pprint.treeify(value))
+        case treemake.Elem(value)   => List(treeify(value))
         case treemake.Tree(value)   => List(value)
         case treemake.Content(list) => list.flatMap(_.treeifyList)
       }
-    def treeify: Iterator[Tree] = treeifyList.iterator
+    def make: Iterator[Tree] = treeifyList.iterator
   }
   private object treemake {
     private case class Quat(q: io.getquill.quat.Quat) extends treemake
@@ -91,14 +92,17 @@ class AstPrinter(traceOpinions: Boolean, traceAstSimple: Boolean, traceQuats: Qu
         Tree.Literal("" + past) // Do not blow up if it is null
 
       case i: Ident =>
-        Tree.Apply("Id", treemake(i.name).withQuat(i.bestQuat).treeify)
+        Tree.Apply("Id", treemake(i.name).withQuat(i.bestQuat).make)
+
+      case i: Infix =>
+        Tree.Apply("Infix", treemake(i.parts).withElem(treemake(i.params)).withQuat(i.bestQuat).make)
 
       case e: Entity if (!traceOpinions) =>
-        Tree.Apply("Entity", treemake(e.name, e.properties).withQuat(e.bestQuat).treeify)
+        Tree.Apply("Entity", treemake(e.name, e.properties).withQuat(e.bestQuat).make)
 
       case q: Quat            => Tree.Literal(q.shortString)
 
-      case s: ScalarValueLift => Tree.Apply("ScalarValueLift", treemake("..." + s.name.reverse.take(15).reverse).withQuat(s.bestQuat).treeify)
+      case s: ScalarValueLift => Tree.Apply("ScalarValueLift", treemake("..." + s.name.reverse.take(15).reverse).withQuat(s.bestQuat).make)
 
       case p: Property if (traceOpinions) =>
         TreeApplyList("Property", l(treeify(p.ast)) ++ l(treeify(p.name)) ++
@@ -116,7 +120,7 @@ class AstPrinter(traceOpinions: Boolean, traceAstSimple: Boolean, traceQuats: Qu
             ))
 
       case e: Entity if (traceOpinions) =>
-        Tree.Apply("Entity", treemake(e.name, e.properties).withTree(printRenameable(e.renameable)).withQuat(e.bestQuat).treeify)
+        Tree.Apply("Entity", treemake(e.name, e.properties).withTree(printRenameable(e.renameable)).withQuat(e.bestQuat).make)
 
       case ast: Ast =>
         if (traceAllQuats)
diff --git a/quill-engine/src/main/scala/io/getquill/norm/RepropagateQuats.scala b/quill-engine/src/main/scala/io/getquill/norm/RepropagateQuats.scala
index 3e3a7ff247..435015e8fc 100644
--- a/quill-engine/src/main/scala/io/getquill/norm/RepropagateQuats.scala
+++ b/quill-engine/src/main/scala/io/getquill/norm/RepropagateQuats.scala
@@ -1,6 +1,6 @@
 package io.getquill.norm
 
-import io.getquill.ast.{ Action, Assignment, AssignmentDual, Ast, ConcatMap, Filter, FlatJoin, FlatMap, GroupBy, Ident, Insert, Join, Map, OnConflict, Property, Query, Returning, ReturningGenerated, SortBy, StatelessTransformer, Update }
+import io.getquill.ast.{ Action, Assignment, AssignmentDual, Ast, ConcatMap, Filter, FlatJoin, FlatMap, GroupBy, Ident, Infix, Insert, Join, Map, OnConflict, Property, Query, Returning, ReturningGenerated, SortBy, StatelessTransformer, Update }
 import io.getquill.quat.Quat
 import io.getquill.quat.Quat.Product
 import io.getquill.util.Interpolator
@@ -64,6 +64,14 @@ object RepropagateQuats extends StatelessTransformer {
     trace"Repropagate ${a.quat.suppress(msg)} from ${a} into:" andReturn f(ar, br, apply(cr))
   }
 
+  override def apply(e: Ast): Ast =
+    e match {
+      case Infix(parts, params, pure, quat) =>
+        val newParams = params.map(apply)
+        Quat.improveInfixQuat(Infix(parts, newParams, pure, quat))
+      case _ => super.apply(e)
+    }
+
   override def apply(e: Query): Query = {
     e match {
       case Filter(a, b, c) => applyBody(a, b, c)(Filter)
diff --git a/quill-engine/src/main/scala/io/getquill/quat/Quat.scala b/quill-engine/src/main/scala/io/getquill/quat/Quat.scala
index 3202293c50..9c1f0dcbfb 100644
--- a/quill-engine/src/main/scala/io/getquill/quat/Quat.scala
+++ b/quill-engine/src/main/scala/io/getquill/quat/Quat.scala
@@ -1,6 +1,6 @@
 package io.getquill.quat
 
-import io.getquill.ast.Ast
+import io.getquill.ast.{ Ast, Infix }
 import io.getquill.quotation.QuatException
 import io.getquill.util.Messages.TraceType
 
@@ -126,7 +126,7 @@ sealed trait Quat {
   def lookup(path: String, failNonExist: Boolean): Quat = (this, path) match {
     case (cc @ Quat.Product(fields), fieldName) =>
       fields.get(fieldName).getOrElse {
-        if (failNonExist)
+        if (failNonExist && cc.tpe == Quat.Product.Type.Concrete)
           throw new IllegalArgumentException(s"The field '${fieldName}' does not exist in an SQL-level type ${cc}")
         else {
           io.getquill.util.Messages.trace(s"The field '${fieldName}' does not exist in an SQL-level type ${cc}. Assuming it's type is Quat.Unknown", traceType = TraceType.Warning)
@@ -156,6 +156,21 @@ object Quat {
     def unapply(ast: Ast) = Some(ast.quat)
   }
 
+  def improveInfixQuat(ast: Ast) =
+    ast match {
+      case Infix(parts, params, pure, Quat.Generic | Quat.Unknown) =>
+        val possiblyBetterQuat = params.foldLeft(Quat.Generic: Quat)((currQuat, param) => currQuat.leastUpperType(param.quat).getOrElse(currQuat))
+        val bestQuat =
+          possiblyBetterQuat match {
+            case Quat.Unknown => Quat.Unknown
+            case Quat.Value   => Quat.Generic
+            case other        => other
+          }
+        Infix(parts, params, pure, bestQuat)
+      case _ =>
+        ast
+    }
+
   import LinkedHashMapOps._
 
   def fromSerializedJVM(serial: String): Quat = KryoQuatSerializer.deserialize(serial)
@@ -203,6 +218,7 @@ object Quat {
     }
 
     def leastUpperTypeProduct(other: Quat.Product): Option[Quat.Product] = {
+      val oneQuatIsAbstract = this.tpe == Product.Type.Abstract || other.tpe == Product.Type.Abstract
       val newFieldsIter =
         fields.zipWith(other.fields) {
           case (key, thisQuat, Some(otherQuat)) => (key, thisQuat.leastUpperType(otherQuat))
@@ -211,7 +227,7 @@ object Quat {
         }
       val newFields = mutable.LinkedHashMap(newFieldsIter.toList: _*)
       val newTpe =
-        if (this.tpe == Product.Type.Abstract || other.tpe == Product.Type.Abstract)
+        if (oneQuatIsAbstract)
           Product.Type.Abstract
         else
           Product.Type.Concrete
diff --git a/quill-sql/src/test/scala/io/getquill/quat/QuatRunSpec.scala b/quill-sql/src/test/scala/io/getquill/quat/QuatRunSpec.scala
new file mode 100644
index 0000000000..bd300dd153
--- /dev/null
+++ b/quill-sql/src/test/scala/io/getquill/quat/QuatRunSpec.scala
@@ -0,0 +1,66 @@
+package io.getquill.quat
+
+import io.getquill._
+
+class QuatRunSpec extends Spec {
+
+  val testContext = new SqlMirrorContext(PostgresDialect, Literal)
+  import testContext._
+
+  "should refine quats from generic infixes and express during execution" - {
+    case class MyPerson(name: String, age: Int)
+    val MyPersonQuat = Quat.Product("name" -> Quat.Value, "age" -> Quat.Value)
+
+    "from extension methods" in {
+      implicit class QueryOps[Q <: Query[_]](q: Q) {
+        def appendFoo = quote(infix"$q APPEND FOO".pure.as[Q])
+      }
+      val q = quote(query[MyPerson].appendFoo)
+      q.ast.quat mustEqual MyPersonQuat // I.e ReifyLiftings runs RepropagateQuats to take care of this
+      testContext.run(q).string mustEqual "SELECT x.name, x.age FROM MyPerson x APPEND FOO"
+    }
+
+    "from extension methods - generic marker" in {
+      implicit class QueryOps[Q <: Query[_]](q: Q) {
+        def appendFoo = quote(infix"$q APPEND FOO".generic.pure.as[Q])
+      }
+      val q = quote(query[MyPerson].appendFoo)
+      q.ast.quat mustEqual MyPersonQuat // I.e ReifyLiftings runs RepropagateQuats to take care of this
+      testContext.run(q).string mustEqual "SELECT x.name, x.age FROM MyPerson x APPEND FOO"
+    }
+
+    "should support query-ops function" in {
+      def appendFooFun[Q <: Query[_]]: Quoted[Q => Q] = quote { (q: Q) => infix"$q APPEND FOO".pure.as[Q] }
+      val q = quote(appendFooFun(query[MyPerson]))
+      q.ast.quat mustEqual Quat.Unknown
+      testContext.run(q).string mustEqual "SELECT x.name, x.age FROM MyPerson x APPEND FOO"
+    }
+
+    "should support query-ops function - dynamic function" in {
+      def appendFooFun[Q <: Query[_]] = quote { (q: Q) => infix"$q APPEND FOO".pure.as[Q] }
+      val q = quote(appendFooFun(query[MyPerson]))
+      q.ast.quat mustEqual MyPersonQuat
+      testContext.run(q).string mustEqual "SELECT x.name, x.age FROM MyPerson x APPEND FOO"
+    }
+
+    "merged with abstract quat" in {
+      trait AbstractPerson { def name: String }
+      case class MyPerson(name: String, age: Int) extends AbstractPerson
+      def filterPerson[P <: AbstractPerson] = quote {
+        (q: Query[P]) => q.filter(p => p.name == "Joe")
+      }
+      val p = quote(filterPerson(query[MyPerson]))
+      testContext.run(p).string mustEqual "SELECT p.name, p.age FROM MyPerson p WHERE p.name = 'Joe'"
+    }
+
+    "merged with abstract quat - dynamic" in {
+      trait AbstractPerson { def name: String }
+      case class MyPerson(name: String, age: Int) extends AbstractPerson
+      def filterPerson[P <: AbstractPerson]: Quoted[Query[P] => Query[P]] = quote {
+        (q: Query[P]) => q.filter(p => p.name == "Joe")
+      }
+      val p = quote(filterPerson(query[MyPerson]))
+      testContext.run(p) mustEqual "SELECT p.name, p.age FROM MyPerson p WHERE p.name = 'Joe'"
+    }
+  }
+}