diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/ATypeBase.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/ATypeBase.rsc
index 62e3fe12171..bda7c86441b 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/ATypeBase.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/ATypeBase.rsc
@@ -39,6 +39,7 @@ extend lang::rascal::\syntax::Rascal;
 import List;
 import Set;
 //import Node;
+import util::Memo;
 import String;
 
 data Keyword
@@ -89,7 +90,7 @@ data AType (str alabel = "")
      | avalue()
      ;
 
-@memo{expireAfter(minutes=5),maximumSize(1000)}
+@memo={expireAfter(minutes=5),maximumSize(1000)}
 AType overloadedAType(rel[loc, IdRole, AType] overloads){
     if(all(<loc _, IdRole _, AType t> <- overloads, aadt(_, _, _) := t)){
       str adtName = "";
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/ModuleLocations.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/ModuleLocations.rsc
index bf72bb487bd..228da061701 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/ModuleLocations.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/ModuleLocations.rsc
@@ -35,6 +35,7 @@ import util::Reflective;
 import util::FileSystem;
 import lang::rascalcore::check::BasicRascalConfig;
 import lang::rascalcore::check::LogicalLocations;
+import util::Memo;
 
 str makeFileName(str qualifiedModuleName, str extension = "rsc") {
     str qnameSlashes = replaceAll(qualifiedModuleName, "::", "/");
@@ -101,7 +102,7 @@ int commonPrefix(list[str] rdir, list[str] rm){
     }
     return size(rm);
 }
-@memo{expireAfter(minutes=5),maximumSize(500)}
+@memo={expireAfter(minutes=5),maximumSize(500)}
 @synopsis{Find the module name corresponding to a given module location via its (src, tpl or logical) location}
 str getRascalModuleName(loc moduleLoc,  PathConfig pcfg){
     modulePath = moduleLoc.path;
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/RascalConfig.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/RascalConfig.rsc
index e02a5287979..1fec2716c42 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/RascalConfig.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/RascalConfig.rsc
@@ -55,6 +55,7 @@ import Map;
 import Set;
 import Relation;
 import String;
+import util::Memo;
 
 str parserPackage = "org.rascalmpl.core.library.lang.rascalcore.grammar.tests.generated_parsers";
 
@@ -136,7 +137,7 @@ bool rascalMayOverload(set[loc] defs, map[loc, Define] defines){
 
 set[IdRole] defBeforeUseRoles = {variableId(), moduleVariableId(), formalId(), keywordFormalId(), patternVariableId()};
 
-@memo{expireAfter(minutes=5),maximumSize(1000)}
+@memo={expireAfter(minutes=5),maximumSize(1000)}
 Accept rascalIsAcceptableSimple(loc def, Use use, Solver s){
     //println("rascalIsAcceptableSimple: *** <use.id> *** def=<def>, use=<use>");
     Define d = s.getDefine(def);
@@ -577,7 +578,7 @@ loc rascalCreateLogicalLoc(Define def, str modelName, PathConfig pcfg){
      return def.defined;
 }
 
-@memo{expireAfter(minutes=5),maximumSize(1000)}
+@memo={expireAfter(minutes=5),maximumSize(1000)}
 rel[str shortName, str longName] getRascalModuleNames(PathConfig pcfg){
     longNames = {};
     for(srcdir <- pcfg.srcs){
diff --git a/src/org/rascalmpl/interpreter/result/NamedFunction.java b/src/org/rascalmpl/interpreter/result/NamedFunction.java
index 4323f410129..8e7d0a4ecc1 100644
--- a/src/org/rascalmpl/interpreter/result/NamedFunction.java
+++ b/src/org/rascalmpl/interpreter/result/NamedFunction.java
@@ -39,6 +39,7 @@
 import io.usethesource.vallang.IConstructor;
 import io.usethesource.vallang.IInteger;
 import io.usethesource.vallang.ISet;
+import io.usethesource.vallang.IString;
 import io.usethesource.vallang.IValue;
 import io.usethesource.vallang.type.Type;
 
@@ -73,6 +74,11 @@ public NamedFunction(AbstractAST ast, IEvaluator<Result<IValue>> eval, Type func
             IValue memoTag = tags.get("memo");
             if (memoTag != null) {
                 this.hasMemoization = true;
+                if (memoTag instanceof IString) {
+                    if (!((IString)memoTag).getValue().isBlank()) {
+                        eval.warning("Ignored memo configuration " + memoTag + ", in most cases `@memo={..}` is needed instead of `@memo{..}`", ((FunctionDeclaration)ast).getTags().getLocation());
+                    }
+                }
                 if (!(memoTag instanceof ISet)) {
                     memoTag = vf.set(memoTag);
                 }
diff --git a/src/org/rascalmpl/library/lang/rascal/tests/basic/Memoization.rsc b/src/org/rascalmpl/library/lang/rascal/tests/basic/Memoization.rsc
index e634d4f75f9..72d175b1cab 100644
--- a/src/org/rascalmpl/library/lang/rascal/tests/basic/Memoization.rsc
+++ b/src/org/rascalmpl/library/lang/rascal/tests/basic/Memoization.rsc
@@ -38,7 +38,7 @@ test bool memoCalledCorrectly2(set[value] x) {
 test bool memoExpire() {
     int callCount2 = 0;
 
-    @memo=maximumSize(10)
+    @memo={maximumSize(10)}
     int call2(int i) {
         callCount2 += 1;
         return callCount2;