diff --git a/ruby/ql/lib/codeql/ruby/ast/Constant.qll b/ruby/ql/lib/codeql/ruby/ast/Constant.qll
index a6658fb63c0..187295d443b 100644
--- a/ruby/ql/lib/codeql/ruby/ast/Constant.qll
+++ b/ruby/ql/lib/codeql/ruby/ast/Constant.qll
@@ -252,6 +252,20 @@ private class ConstantReadAccessSynth extends ConstantAccess, TConstantReadAcces
   final override predicate hasGlobalScope() { value.matches("::%") }
 }
 
+private class ConstantWriteAccessSynth extends ConstantAccess, TConstantWriteAccessSynth {
+  private string value;
+
+  ConstantWriteAccessSynth() { this = TConstantWriteAccessSynth(_, _, value) }
+
+  final override string getName() {
+    if this.hasGlobalScope() then result = value.suffix(2) else result = value
+  }
+
+  final override Expr getScopeExpr() { synthChild(this, 0, result) }
+
+  final override predicate hasGlobalScope() { value.matches("::%") }
+}
+
 /**
  * A use (read) of a constant.
  *
@@ -323,7 +337,9 @@ class ConstantReadAccess extends ConstantAccess {
  */
 class ConstantWriteAccess extends ConstantAccess {
   ConstantWriteAccess() {
-    explicitAssignmentNode(toGenerated(this), _) or this instanceof TNamespace
+    explicitAssignmentNode(toGenerated(this), _) or
+    this instanceof TNamespace or
+    this instanceof TConstantWriteAccessSynth
   }
 
   override string getAPrimaryQlClass() { result = "ConstantWriteAccess" }
diff --git a/ruby/ql/lib/codeql/ruby/ast/Expr.qll b/ruby/ql/lib/codeql/ruby/ast/Expr.qll
index 3468c733d0d..265190ca275 100644
--- a/ruby/ql/lib/codeql/ruby/ast/Expr.qll
+++ b/ruby/ql/lib/codeql/ruby/ast/Expr.qll
@@ -61,7 +61,7 @@ class ArgumentList extends Expr, TArgumentList {
 
 private class LhsExpr_ =
   TVariableAccess or TTokenConstantAccess or TScopeResolutionConstantAccess or TMethodCall or
-      TDestructuredLhsExpr;
+      TDestructuredLhsExpr or TConstantWriteAccessSynth;
 
 /**
  * A "left-hand-side" (LHS) expression. An `LhsExpr` can occur on the left-hand side of
diff --git a/ruby/ql/lib/codeql/ruby/ast/internal/AST.qll b/ruby/ql/lib/codeql/ruby/ast/internal/AST.qll
index 821656f1f5f..7b94df3b773 100644
--- a/ruby/ql/lib/codeql/ruby/ast/internal/AST.qll
+++ b/ruby/ql/lib/codeql/ruby/ast/internal/AST.qll
@@ -116,6 +116,9 @@ private module Cached {
     TConstantReadAccessSynth(Ast::AstNode parent, int i, string value) {
       mkSynthChild(ConstantReadAccessKind(value), parent, i)
     } or
+    TConstantWriteAccessSynth(Ast::AstNode parent, int i, string value) {
+      mkSynthChild(ConstantWriteAccessKind(value), parent, i)
+    } or
     TDefinedExpr(Ruby::Unary g) { g instanceof @ruby_unary_definedquestion } or
     TDelimitedSymbolLiteral(Ruby::DelimitedSymbol g) or
     TDestructuredLeftAssignment(Ruby::DestructuredLeftAssignment g) {
@@ -373,12 +376,13 @@ private module Cached {
   class TAstNodeSynth =
     TAddExprSynth or TAssignExprSynth or TBitwiseAndExprSynth or TBitwiseOrExprSynth or
         TBitwiseXorExprSynth or TBraceBlockSynth or TClassVariableAccessSynth or
-        TConstantReadAccessSynth or TDivExprSynth or TExponentExprSynth or
-        TGlobalVariableAccessSynth or TIfSynth or TInstanceVariableAccessSynth or
-        TIntegerLiteralSynth or TLShiftExprSynth or TLocalVariableAccessSynth or
-        TLogicalAndExprSynth or TLogicalOrExprSynth or TMethodCallSynth or TModuloExprSynth or
-        TMulExprSynth or TNilLiteralSynth or TRShiftExprSynth or TRangeLiteralSynth or TSelfSynth or
-        TSimpleParameterSynth or TSplatExprSynth or TStmtSequenceSynth or TSubExprSynth;
+        TConstantReadAccessSynth or TConstantWriteAccessSynth or TDivExprSynth or
+        TExponentExprSynth or TGlobalVariableAccessSynth or TIfSynth or
+        TInstanceVariableAccessSynth or TIntegerLiteralSynth or TLShiftExprSynth or
+        TLocalVariableAccessSynth or TLogicalAndExprSynth or TLogicalOrExprSynth or
+        TMethodCallSynth or TModuloExprSynth or TMulExprSynth or TNilLiteralSynth or
+        TRShiftExprSynth or TRangeLiteralSynth or TSelfSynth or TSimpleParameterSynth or
+        TSplatExprSynth or TStmtSequenceSynth or TSubExprSynth;
 
   /**
    * Gets the underlying TreeSitter entity for a given AST node. This does not
@@ -565,6 +569,8 @@ private module Cached {
     or
     result = TConstantReadAccessSynth(parent, i, _)
     or
+    result = TConstantWriteAccessSynth(parent, i, _)
+    or
     result = TDivExprSynth(parent, i)
     or
     result = TExponentExprSynth(parent, i)
@@ -672,7 +678,8 @@ class TMethodCall =
 class TSuperCall = TTokenSuperCall or TRegularSuperCall;
 
 class TConstantAccess =
-  TTokenConstantAccess or TScopeResolutionConstantAccess or TNamespace or TConstantReadAccessSynth;
+  TTokenConstantAccess or TScopeResolutionConstantAccess or TNamespace or
+      TConstantReadAccessSynth or TConstantWriteAccessSynth;
 
 class TControlExpr = TConditionalExpr or TCaseExpr or TCaseMatch or TLoop;
 
diff --git a/ruby/ql/lib/codeql/ruby/ast/internal/Synthesis.qll b/ruby/ql/lib/codeql/ruby/ast/internal/Synthesis.qll
index 1ab4435a85a..43f89740908 100644
--- a/ruby/ql/lib/codeql/ruby/ast/internal/Synthesis.qll
+++ b/ruby/ql/lib/codeql/ruby/ast/internal/Synthesis.qll
@@ -42,7 +42,8 @@ newtype SynthKind =
   StmtSequenceKind() or
   SelfKind(SelfVariable v) or
   SubExprKind() or
-  ConstantReadAccessKind(string value) { any(Synthesis s).constantReadAccess(value) }
+  ConstantReadAccessKind(string value) { any(Synthesis s).constantReadAccess(value) } or
+  ConstantWriteAccessKind(string value) { any(Synthesis s).constantWriteAccess(value) }
 
 /**
  * An AST child.
@@ -107,6 +108,11 @@ class Synthesis extends TSynthesis {
    */
   predicate constantReadAccess(string name) { none() }
 
+  /**
+   * Holds if a constant write access of `name` is needed.
+   */
+  predicate constantWriteAccess(string name) { none() }
+
   /**
    * Holds if `n` should be excluded from `ControlFlowTree` in the CFG construction.
    */
@@ -493,6 +499,231 @@ private module AssignOperationDesugar {
     }
   }
 
+  /**
+   * An assignment operation where the left-hand side is a constant
+   * without scope expression, such as`FOO` or `::Foo`.
+   */
+  private class ConstantAssignOperation extends AssignOperation {
+    string name;
+
+    pragma[nomagic]
+    ConstantAssignOperation() {
+      name =
+        any(Ruby::Constant constant | TTokenConstantAccess(constant) = this.getLeftOperand())
+            .getValue()
+      or
+      name =
+        "::" +
+          any(Ruby::Constant constant |
+            TScopeResolutionConstantAccess(any(Ruby::ScopeResolution g | not exists(g.getScope())),
+              constant) = this.getLeftOperand()
+          ).getValue()
+    }
+
+    final string getName() { result = name }
+  }
+
+  pragma[nomagic]
+  private predicate constantAssignOperationSynthesis(AstNode parent, int i, Child child) {
+    exists(ConstantAssignOperation cao |
+      parent = cao and
+      i = -1 and
+      child = SynthChild(AssignExprKind())
+      or
+      exists(AstNode assign | assign = TAssignExprSynth(cao, -1) |
+        parent = assign and
+        i = 0 and
+        child = childRef(cao.getLeftOperand())
+        or
+        parent = assign and
+        i = 1 and
+        child = SynthChild(getKind(cao))
+        or
+        parent = getSynthChild(assign, 1) and
+        (
+          i = 0 and
+          child = SynthChild(ConstantReadAccessKind(cao.getName()))
+          or
+          i = 1 and
+          child = childRef(cao.getRightOperand())
+        )
+      )
+    )
+  }
+
+  /**
+   * ```rb
+   * FOO += y
+   * ```
+   *
+   * desugars to
+   *
+   * ```rb
+   * FOO = FOO + y
+   * ```
+   */
+  private class ConstantAssignOperationSynthesis extends Synthesis {
+    final override predicate child(AstNode parent, int i, Child child) {
+      constantAssignOperationSynthesis(parent, i, child)
+    }
+
+    final override predicate constantReadAccess(string name) {
+      name = any(ConstantAssignOperation o).getName()
+    }
+
+    final override predicate location(AstNode n, Location l) {
+      exists(ConstantAssignOperation cao, BinaryOperation bo |
+        bo = cao.getDesugared().(AssignExpr).getRightOperand()
+      |
+        n = bo and
+        l = getAssignOperationLocation(cao)
+        or
+        n = bo.getLeftOperand() and
+        hasLocation(cao.getLeftOperand(), l)
+      )
+    }
+  }
+
+  /**
+   * An assignment operation where the left-hand side is a constant
+   * with scope expression, such as `expr::FOO`.
+   */
+  private class ScopeResolutionAssignOperation extends AssignOperation {
+    string name;
+    Expr scope;
+
+    pragma[nomagic]
+    ScopeResolutionAssignOperation() {
+      exists(Ruby::Constant constant, Ruby::ScopeResolution g |
+        TScopeResolutionConstantAccess(g, constant) = this.getLeftOperand() and
+        name = constant.getValue() and
+        toGenerated(scope) = g.getScope()
+      )
+    }
+
+    final string getName() { result = name }
+
+    final Expr getScopeExpr() { result = scope }
+  }
+
+  pragma[nomagic]
+  private predicate scopeResolutionAssignOperationSynthesis(AstNode parent, int i, Child child) {
+    exists(ScopeResolutionAssignOperation cao |
+      parent = cao and
+      i = -1 and
+      child = SynthChild(StmtSequenceKind())
+      or
+      exists(AstNode stmts | stmts = TStmtSequenceSynth(cao, -1) |
+        parent = stmts and
+        i = 0 and
+        child = SynthChild(AssignExprKind())
+        or
+        exists(AstNode assign | assign = TAssignExprSynth(stmts, 0) |
+          parent = assign and
+          i = 0 and
+          child = SynthChild(LocalVariableAccessSynthKind(TLocalVariableSynth(cao, 0)))
+          or
+          parent = assign and
+          i = 1 and
+          child = childRef(cao.getScopeExpr())
+        )
+        or
+        parent = stmts and
+        i = 1 and
+        child = SynthChild(AssignExprKind())
+        or
+        exists(AstNode assign | assign = TAssignExprSynth(stmts, 1) |
+          parent = assign and
+          i = 0 and
+          child = SynthChild(ConstantWriteAccessKind(cao.getName()))
+          or
+          exists(AstNode cwa | cwa = TConstantWriteAccessSynth(assign, 0, cao.getName()) |
+            parent = cwa and
+            i = 0 and
+            child = SynthChild(LocalVariableAccessSynthKind(TLocalVariableSynth(cao, 0)))
+          )
+          or
+          parent = assign and
+          i = 1 and
+          child = SynthChild(getKind(cao))
+          or
+          exists(AstNode op | op = getSynthChild(assign, 1) |
+            parent = op and
+            i = 0 and
+            child = SynthChild(ConstantReadAccessKind(cao.getName()))
+            or
+            exists(AstNode cra | cra = TConstantReadAccessSynth(op, 0, cao.getName()) |
+              parent = cra and
+              i = 0 and
+              child = SynthChild(LocalVariableAccessSynthKind(TLocalVariableSynth(cao, 0)))
+            )
+            or
+            parent = op and
+            i = 1 and
+            child = childRef(cao.getRightOperand())
+          )
+        )
+      )
+    )
+  }
+
+  /**
+   * ```rb
+   * expr::FOO += y
+   * ```
+   *
+   * desugars to
+   *
+   * ```rb
+   * __synth__0 = expr
+   * __synth__0::FOO = _synth__0::FOO + y
+   * ```
+   */
+  private class ScopeResolutionAssignOperationSynthesis extends Synthesis {
+    final override predicate child(AstNode parent, int i, Child child) {
+      scopeResolutionAssignOperationSynthesis(parent, i, child)
+    }
+
+    final override predicate constantReadAccess(string name) {
+      name = any(ScopeResolutionAssignOperation o).getName()
+    }
+
+    final override predicate localVariable(AstNode n, int i) {
+      n instanceof ScopeResolutionAssignOperation and
+      i = 0
+    }
+
+    final override predicate constantWriteAccess(string name) { this.constantReadAccess(name) }
+
+    final override predicate location(AstNode n, Location l) {
+      exists(ScopeResolutionAssignOperation cao, StmtSequence stmts | stmts = cao.getDesugared() |
+        n = stmts.getStmt(0) and
+        hasLocation(cao.getScopeExpr(), l)
+        or
+        exists(AssignExpr assign | assign = stmts.getStmt(1) |
+          n = assign and hasLocation(cao, l)
+          or
+          n = assign.getLeftOperand() and
+          hasLocation(cao.getLeftOperand(), l)
+          or
+          n = assign.getLeftOperand().(ConstantAccess).getScopeExpr() and
+          hasLocation(cao.getScopeExpr(), l)
+          or
+          exists(BinaryOperation bo | bo = assign.getRightOperand() |
+            n = bo and
+            l = getAssignOperationLocation(cao)
+            or
+            n = bo.getLeftOperand() and
+            hasLocation(cao.getLeftOperand(), l)
+            or
+            n = bo.getLeftOperand().(ConstantAccess).getScopeExpr() and
+            hasLocation(cao.getScopeExpr(), l)
+          )
+        )
+      )
+    }
+  }
+
   /** An assignment operation where the left-hand side is a method call. */
   private class SetterAssignOperation extends AssignOperation {
     private MethodCall mc;
diff --git a/ruby/ql/lib/codeql/ruby/controlflow/internal/ControlFlowGraphImpl.qll b/ruby/ql/lib/codeql/ruby/controlflow/internal/ControlFlowGraphImpl.qll
index 03e919ec654..bdd67d2a693 100644
--- a/ruby/ql/lib/codeql/ruby/controlflow/internal/ControlFlowGraphImpl.qll
+++ b/ruby/ql/lib/codeql/ruby/controlflow/internal/ControlFlowGraphImpl.qll
@@ -890,7 +890,12 @@ module Trees {
   private class ConstantAccessTree extends PostOrderTree, ConstantAccess {
     ConstantAccessTree() {
       not this instanceof ClassDeclaration and
-      not this instanceof ModuleDeclaration
+      not this instanceof ModuleDeclaration and
+      // constant accesses with scope expression in compound assignments are desugared
+      not (
+        this = any(AssignOperation op).getLeftOperand() and
+        exists(this.getScopeExpr())
+      )
     }
 
     final override predicate propagatesAbnormal(AstNode child) { child = this.getScopeExpr() }
diff --git a/ruby/ql/test/library-tests/ast/Ast.expected b/ruby/ql/test/library-tests/ast/Ast.expected
index 33229c64393..6701f5ce160 100644
--- a/ruby/ql/test/library-tests/ast/Ast.expected
+++ b/ruby/ql/test/library-tests/ast/Ast.expected
@@ -2833,6 +2833,29 @@ operations/operations.rb:
 #   96|   getStmt: [AssignMulExpr] ... *= ...
 #   96|     getAnOperand/getLeftOperand: [GlobalVariableAccess] $global_var
 #   96|     getAnOperand/getRightOperand: [IntegerLiteral] 6
+#   98|   getStmt: [AssignExpr] ... = ...
+#   98|     getAnOperand/getLeftOperand: [ConstantAssignment] CONSTANT1
+#   98|     getAnOperand/getRightOperand: [IntegerLiteral] 5
+#   99|   getStmt: [AssignAddExpr] ... += ...
+#   99|     getAnOperand/getLeftOperand: [ConstantAssignment, ConstantReadAccess] CONSTANT2
+#   99|     getAnOperand/getRightOperand: [IntegerLiteral] 6
+#  100|   getStmt: [AssignLogicalOrExpr] ... ||= ...
+#  100|     getAnOperand/getLeftOperand: [ConstantAssignment, ConstantReadAccess] CONSTANT3
+#  100|     getAnOperand/getRightOperand: [IntegerLiteral] 7
+#  101|   getStmt: [AssignLogicalOrExpr] ... ||= ...
+#  101|     getAnOperand/getLeftOperand: [ConstantAssignment, ConstantReadAccess] MemberConstant
+#  101|       getScopeExpr: [ConstantReadAccess] Foo
+#  101|     getAnOperand/getRightOperand: [IntegerLiteral] 8
+#  102|   getStmt: [AssignLogicalOrExpr] ... ||= ...
+#  102|     getAnOperand/getLeftOperand: [ConstantAssignment, ConstantReadAccess] OtherConstant
+#  102|       getScopeExpr: [MethodCall] call to bar
+#  102|         getReceiver: [MethodCall] call to foo
+#  102|           getReceiver: [SelfVariableAccess] self
+#  102|           getArgument: [IntegerLiteral] 1
+#  102|     getAnOperand/getRightOperand: [IntegerLiteral] 7
+#  103|   getStmt: [AssignLogicalOrExpr] ... ||= ...
+#  103|     getAnOperand/getLeftOperand: [ConstantAssignment, ConstantReadAccess] CONSTANT4
+#  103|     getAnOperand/getRightOperand: [IntegerLiteral] 7
 params/params.rb:
 #    1| [Toplevel] params.rb
 #    4|   getStmt: [Method] identifier_method_params
diff --git a/ruby/ql/test/library-tests/ast/AstDesugar.expected b/ruby/ql/test/library-tests/ast/AstDesugar.expected
index 8be5246ab88..45711cd2927 100644
--- a/ruby/ql/test/library-tests/ast/AstDesugar.expected
+++ b/ruby/ql/test/library-tests/ast/AstDesugar.expected
@@ -865,6 +865,51 @@ operations/operations.rb:
 #   96|     getAnOperand/getRightOperand: [MulExpr] ... * ...
 #   96|       getAnOperand/getLeftOperand/getReceiver: [GlobalVariableAccess] $global_var
 #   96|       getAnOperand/getArgument/getRightOperand: [IntegerLiteral] 6
+#   99| [AssignAddExpr] ... += ...
+#   99|   getDesugared: [AssignExpr] ... = ...
+#   99|     getAnOperand/getLeftOperand: [ConstantAssignment, ConstantReadAccess] CONSTANT2
+#   99|     getAnOperand/getRightOperand: [AddExpr] ... + ...
+#   99|       getAnOperand/getLeftOperand/getReceiver: [ConstantReadAccess] CONSTANT2
+#   99|       getAnOperand/getArgument/getRightOperand: [IntegerLiteral] 6
+#  100| [AssignLogicalOrExpr] ... ||= ...
+#  100|   getDesugared: [AssignExpr] ... = ...
+#  100|     getAnOperand/getLeftOperand: [ConstantAssignment, ConstantReadAccess] CONSTANT3
+#  100|     getAnOperand/getRightOperand: [LogicalOrExpr] ... || ...
+#  100|       getAnOperand/getLeftOperand/getReceiver: [ConstantReadAccess] CONSTANT3
+#  100|       getAnOperand/getArgument/getRightOperand: [IntegerLiteral] 7
+#  101| [AssignLogicalOrExpr] ... ||= ...
+#  101|   getDesugared: [StmtSequence] ...
+#  101|     getStmt: [AssignExpr] ... = ...
+#  101|       getAnOperand/getRightOperand: [ConstantReadAccess] Foo
+#  101|       getAnOperand/getLeftOperand: [LocalVariableAccess] __synth__0
+#  101|     getStmt: [AssignExpr] ... = ...
+#  101|       getAnOperand/getLeftOperand: [ConstantAssignment] MemberConstant
+#  101|         getScopeExpr: [LocalVariableAccess] __synth__0
+#  101|       getAnOperand/getRightOperand: [LogicalOrExpr] ... || ...
+#  101|         getAnOperand/getLeftOperand/getReceiver: [ConstantReadAccess] MemberConstant
+#  101|           getScopeExpr: [LocalVariableAccess] __synth__0
+#  101|         getAnOperand/getArgument/getRightOperand: [IntegerLiteral] 8
+#  102| [AssignLogicalOrExpr] ... ||= ...
+#  102|   getDesugared: [StmtSequence] ...
+#  102|     getStmt: [AssignExpr] ... = ...
+#  102|       getAnOperand/getRightOperand: [MethodCall] call to bar
+#  102|         getReceiver: [MethodCall] call to foo
+#  102|           getReceiver: [SelfVariableAccess] self
+#  102|           getArgument: [IntegerLiteral] 1
+#  102|       getAnOperand/getLeftOperand: [LocalVariableAccess] __synth__0
+#  102|     getStmt: [AssignExpr] ... = ...
+#  102|       getAnOperand/getLeftOperand: [ConstantAssignment] OtherConstant
+#  102|         getScopeExpr: [LocalVariableAccess] __synth__0
+#  102|       getAnOperand/getRightOperand: [LogicalOrExpr] ... || ...
+#  102|         getAnOperand/getLeftOperand/getReceiver: [ConstantReadAccess] OtherConstant
+#  102|           getScopeExpr: [LocalVariableAccess] __synth__0
+#  102|         getAnOperand/getArgument/getRightOperand: [IntegerLiteral] 7
+#  103| [AssignLogicalOrExpr] ... ||= ...
+#  103|   getDesugared: [AssignExpr] ... = ...
+#  103|     getAnOperand/getLeftOperand: [ConstantAssignment, ConstantReadAccess] CONSTANT4
+#  103|     getAnOperand/getRightOperand: [LogicalOrExpr] ... || ...
+#  103|       getAnOperand/getLeftOperand/getReceiver: [ConstantReadAccess] CONSTANT4
+#  103|       getAnOperand/getArgument/getRightOperand: [IntegerLiteral] 7
 params/params.rb:
 #    8| [HashLiteral] {...}
 #    8|   getDesugared: [MethodCall] call to []
diff --git a/ruby/ql/test/library-tests/ast/TreeSitter.expected b/ruby/ql/test/library-tests/ast/TreeSitter.expected
index 839ad55fb38..a0e32ce0aa4 100644
--- a/ruby/ql/test/library-tests/ast/TreeSitter.expected
+++ b/ruby/ql/test/library-tests/ast/TreeSitter.expected
@@ -5537,6 +5537,46 @@ operations/operations.rb:
 #   96|     0: [GlobalVariable] $global_var
 #   96|     1: [ReservedWord] *=
 #   96|     2: [Integer] 6
+#   98|   66: [Assignment] Assignment
+#   98|     0: [Constant] CONSTANT1
+#   98|     1: [ReservedWord] =
+#   98|     2: [Integer] 5
+#   99|   67: [OperatorAssignment] OperatorAssignment
+#   99|     0: [Constant] CONSTANT2
+#   99|     1: [ReservedWord] +=
+#   99|     2: [Integer] 6
+#  100|   68: [OperatorAssignment] OperatorAssignment
+#  100|     0: [Constant] CONSTANT3
+#  100|     1: [ReservedWord] ||=
+#  100|     2: [Integer] 7
+#  101|   69: [OperatorAssignment] OperatorAssignment
+#  101|     0: [ScopeResolution] ScopeResolution
+#  101|       0: [Constant] Foo
+#  101|       1: [ReservedWord] ::
+#  101|       2: [Constant] MemberConstant
+#  101|     1: [ReservedWord] ||=
+#  101|     2: [Integer] 8
+#  102|   70: [OperatorAssignment] OperatorAssignment
+#  102|     0: [ScopeResolution] ScopeResolution
+#  102|       0: [Call] Call
+#  102|         0: [Call] Call
+#  102|           0: [Identifier] foo
+#  102|           1: [ArgumentList] ArgumentList
+#  102|             0: [ReservedWord] (
+#  102|             1: [Integer] 1
+#  102|             2: [ReservedWord] )
+#  102|         1: [ReservedWord] .
+#  102|         2: [Identifier] bar
+#  102|       1: [ReservedWord] ::
+#  102|       2: [Constant] OtherConstant
+#  102|     1: [ReservedWord] ||=
+#  102|     2: [Integer] 7
+#  103|   71: [OperatorAssignment] OperatorAssignment
+#  103|     0: [ScopeResolution] ScopeResolution
+#  103|       0: [ReservedWord] ::
+#  103|       1: [Constant] CONSTANT4
+#  103|     1: [ReservedWord] ||=
+#  103|     2: [Integer] 7
 #    1| [Comment] # Start with assignments to all the identifiers used below, so that they are
 #    2| [Comment] # interpreted as variables.
 #   22| [Comment] # Unary operations
diff --git a/ruby/ql/test/library-tests/ast/ValueText.expected b/ruby/ql/test/library-tests/ast/ValueText.expected
index 1492d619e33..cec6e7ad3a3 100644
--- a/ruby/ql/test/library-tests/ast/ValueText.expected
+++ b/ruby/ql/test/library-tests/ast/ValueText.expected
@@ -888,6 +888,13 @@ exprValue
 | operations/operations.rb:92:10:92:10 | 4 | 4 | int |
 | operations/operations.rb:95:15:95:15 | 5 | 5 | int |
 | operations/operations.rb:96:16:96:16 | 6 | 6 | int |
+| operations/operations.rb:98:13:98:13 | 5 | 5 | int |
+| operations/operations.rb:99:14:99:14 | 6 | 6 | int |
+| operations/operations.rb:100:15:100:15 | 7 | 7 | int |
+| operations/operations.rb:101:25:101:25 | 8 | 8 | int |
+| operations/operations.rb:102:5:102:5 | 1 | 1 | int |
+| operations/operations.rb:102:31:102:31 | 7 | 7 | int |
+| operations/operations.rb:103:17:103:17 | 7 | 7 | int |
 | params/params.rb:41:46:41:46 | 7 | 7 | int |
 | params/params.rb:47:19:47:21 | :bar | :bar | symbol |
 | params/params.rb:47:24:47:24 | 2 | 2 | int |
@@ -1764,6 +1771,13 @@ exprCfgNodeValue
 | operations/operations.rb:92:10:92:10 | 4 | 4 | int |
 | operations/operations.rb:95:15:95:15 | 5 | 5 | int |
 | operations/operations.rb:96:16:96:16 | 6 | 6 | int |
+| operations/operations.rb:98:13:98:13 | 5 | 5 | int |
+| operations/operations.rb:99:14:99:14 | 6 | 6 | int |
+| operations/operations.rb:100:15:100:15 | 7 | 7 | int |
+| operations/operations.rb:101:25:101:25 | 8 | 8 | int |
+| operations/operations.rb:102:5:102:5 | 1 | 1 | int |
+| operations/operations.rb:102:31:102:31 | 7 | 7 | int |
+| operations/operations.rb:103:17:103:17 | 7 | 7 | int |
 | params/params.rb:41:46:41:46 | 7 | 7 | int |
 | params/params.rb:47:19:47:21 | :bar | :bar | symbol |
 | params/params.rb:47:24:47:24 | 2 | 2 | int |
diff --git a/ruby/ql/test/library-tests/ast/operations/assignment.expected b/ruby/ql/test/library-tests/ast/operations/assignment.expected
index 7a536f183f7..ef88dc1751a 100644
--- a/ruby/ql/test/library-tests/ast/operations/assignment.expected
+++ b/ruby/ql/test/library-tests/ast/operations/assignment.expected
@@ -52,6 +52,19 @@ assignments
 | operations.rb:95:1:95:15 | ... = ... | = | operations.rb:95:1:95:11 | $global_var | operations.rb:95:15:95:15 | 5 | AssignExpr |
 | operations.rb:96:1:96:16 | ... *= ... | *= | operations.rb:96:1:96:11 | $global_var | operations.rb:96:16:96:16 | 6 | AssignMulExpr |
 | operations.rb:96:1:96:16 | ... = ... | = | operations.rb:96:1:96:11 | $global_var | operations.rb:96:13:96:14 | ... * ... | AssignExpr |
+| operations.rb:98:1:98:13 | ... = ... | = | operations.rb:98:1:98:9 | CONSTANT1 | operations.rb:98:13:98:13 | 5 | AssignExpr |
+| operations.rb:99:1:99:14 | ... += ... | += | operations.rb:99:1:99:9 | CONSTANT2 | operations.rb:99:14:99:14 | 6 | AssignAddExpr |
+| operations.rb:99:1:99:14 | ... = ... | = | operations.rb:99:1:99:9 | CONSTANT2 | operations.rb:99:11:99:12 | ... + ... | AssignExpr |
+| operations.rb:100:1:100:15 | ... = ... | = | operations.rb:100:1:100:9 | CONSTANT3 | operations.rb:100:11:100:13 | ... \|\| ... | AssignExpr |
+| operations.rb:100:1:100:15 | ... \|\|= ... | \|\|= | operations.rb:100:1:100:9 | CONSTANT3 | operations.rb:100:15:100:15 | 7 | AssignLogicalOrExpr |
+| operations.rb:101:1:101:3 | ... = ... | = | operations.rb:101:1:101:3 | __synth__0 | operations.rb:101:1:101:3 | Foo | AssignExpr |
+| operations.rb:101:1:101:25 | ... = ... | = | operations.rb:101:1:101:19 | MemberConstant | operations.rb:101:21:101:23 | ... \|\| ... | AssignExpr |
+| operations.rb:101:1:101:25 | ... \|\|= ... | \|\|= | operations.rb:101:1:101:19 | MemberConstant | operations.rb:101:25:101:25 | 8 | AssignLogicalOrExpr |
+| operations.rb:102:1:102:10 | ... = ... | = | operations.rb:102:1:102:10 | __synth__0 | operations.rb:102:1:102:10 | call to bar | AssignExpr |
+| operations.rb:102:1:102:31 | ... = ... | = | operations.rb:102:1:102:25 | OtherConstant | operations.rb:102:27:102:29 | ... \|\| ... | AssignExpr |
+| operations.rb:102:1:102:31 | ... \|\|= ... | \|\|= | operations.rb:102:1:102:25 | OtherConstant | operations.rb:102:31:102:31 | 7 | AssignLogicalOrExpr |
+| operations.rb:103:1:103:17 | ... = ... | = | operations.rb:103:1:103:11 | CONSTANT4 | operations.rb:103:13:103:15 | ... \|\| ... | AssignExpr |
+| operations.rb:103:1:103:17 | ... \|\|= ... | \|\|= | operations.rb:103:1:103:11 | CONSTANT4 | operations.rb:103:17:103:17 | 7 | AssignLogicalOrExpr |
 assignOperations
 | operations.rb:69:1:69:8 | ... += ... | += | operations.rb:69:1:69:1 | x | operations.rb:69:6:69:8 | 128 | AssignAddExpr |
 | operations.rb:70:1:70:7 | ... -= ... | -= | operations.rb:70:1:70:1 | y | operations.rb:70:6:70:7 | 32 | AssignSubExpr |
@@ -69,6 +82,11 @@ assignOperations
 | operations.rb:89:3:89:9 | ... += ... | += | operations.rb:89:3:89:4 | @x | operations.rb:89:9:89:9 | 2 | AssignAddExpr |
 | operations.rb:92:3:92:10 | ... /= ... | /= | operations.rb:92:3:92:5 | @@y | operations.rb:92:10:92:10 | 4 | AssignDivExpr |
 | operations.rb:96:1:96:16 | ... *= ... | *= | operations.rb:96:1:96:11 | $global_var | operations.rb:96:16:96:16 | 6 | AssignMulExpr |
+| operations.rb:99:1:99:14 | ... += ... | += | operations.rb:99:1:99:9 | CONSTANT2 | operations.rb:99:14:99:14 | 6 | AssignAddExpr |
+| operations.rb:100:1:100:15 | ... \|\|= ... | \|\|= | operations.rb:100:1:100:9 | CONSTANT3 | operations.rb:100:15:100:15 | 7 | AssignLogicalOrExpr |
+| operations.rb:101:1:101:25 | ... \|\|= ... | \|\|= | operations.rb:101:1:101:19 | MemberConstant | operations.rb:101:25:101:25 | 8 | AssignLogicalOrExpr |
+| operations.rb:102:1:102:31 | ... \|\|= ... | \|\|= | operations.rb:102:1:102:25 | OtherConstant | operations.rb:102:31:102:31 | 7 | AssignLogicalOrExpr |
+| operations.rb:103:1:103:17 | ... \|\|= ... | \|\|= | operations.rb:103:1:103:11 | CONSTANT4 | operations.rb:103:17:103:17 | 7 | AssignLogicalOrExpr |
 assignArithmeticOperations
 | operations.rb:69:1:69:8 | ... += ... | += | operations.rb:69:1:69:1 | x | operations.rb:69:6:69:8 | 128 | AssignAddExpr |
 | operations.rb:70:1:70:7 | ... -= ... | -= | operations.rb:70:1:70:1 | y | operations.rb:70:6:70:7 | 32 | AssignSubExpr |
@@ -79,9 +97,14 @@ assignArithmeticOperations
 | operations.rb:89:3:89:9 | ... += ... | += | operations.rb:89:3:89:4 | @x | operations.rb:89:9:89:9 | 2 | AssignAddExpr |
 | operations.rb:92:3:92:10 | ... /= ... | /= | operations.rb:92:3:92:5 | @@y | operations.rb:92:10:92:10 | 4 | AssignDivExpr |
 | operations.rb:96:1:96:16 | ... *= ... | *= | operations.rb:96:1:96:11 | $global_var | operations.rb:96:16:96:16 | 6 | AssignMulExpr |
+| operations.rb:99:1:99:14 | ... += ... | += | operations.rb:99:1:99:9 | CONSTANT2 | operations.rb:99:14:99:14 | 6 | AssignAddExpr |
 assignLogicalOperations
 | operations.rb:77:2:77:8 | ... &&= ... | &&= | operations.rb:77:2:77:2 | x | operations.rb:77:8:77:8 | y | AssignLogicalAndExpr |
 | operations.rb:78:2:78:8 | ... \|\|= ... | \|\|= | operations.rb:78:2:78:2 | a | operations.rb:78:8:78:8 | b | AssignLogicalOrExpr |
+| operations.rb:100:1:100:15 | ... \|\|= ... | \|\|= | operations.rb:100:1:100:9 | CONSTANT3 | operations.rb:100:15:100:15 | 7 | AssignLogicalOrExpr |
+| operations.rb:101:1:101:25 | ... \|\|= ... | \|\|= | operations.rb:101:1:101:19 | MemberConstant | operations.rb:101:25:101:25 | 8 | AssignLogicalOrExpr |
+| operations.rb:102:1:102:31 | ... \|\|= ... | \|\|= | operations.rb:102:1:102:25 | OtherConstant | operations.rb:102:31:102:31 | 7 | AssignLogicalOrExpr |
+| operations.rb:103:1:103:17 | ... \|\|= ... | \|\|= | operations.rb:103:1:103:11 | CONSTANT4 | operations.rb:103:17:103:17 | 7 | AssignLogicalOrExpr |
 assignBitwiseOperations
 | operations.rb:81:2:81:8 | ... <<= ... | <<= | operations.rb:81:2:81:2 | x | operations.rb:81:8:81:8 | 2 | AssignLShiftExpr |
 | operations.rb:82:2:82:8 | ... >>= ... | >>= | operations.rb:82:2:82:2 | y | operations.rb:82:8:82:8 | 3 | AssignRShiftExpr |
diff --git a/ruby/ql/test/library-tests/ast/operations/binary.expected b/ruby/ql/test/library-tests/ast/operations/binary.expected
index 236b0c3b574..e94a1dc7643 100644
--- a/ruby/ql/test/library-tests/ast/operations/binary.expected
+++ b/ruby/ql/test/library-tests/ast/operations/binary.expected
@@ -40,6 +40,11 @@ binaryOperations
 | operations.rb:89:6:89:7 | ... + ... | + | operations.rb:89:3:89:4 | @x | operations.rb:89:9:89:9 | 2 | AddExpr |
 | operations.rb:92:7:92:8 | ... / ... | / | operations.rb:92:3:92:5 | @@y | operations.rb:92:10:92:10 | 4 | DivExpr |
 | operations.rb:96:13:96:14 | ... * ... | * | operations.rb:96:1:96:11 | $global_var | operations.rb:96:16:96:16 | 6 | MulExpr |
+| operations.rb:99:11:99:12 | ... + ... | + | operations.rb:99:1:99:9 | CONSTANT2 | operations.rb:99:14:99:14 | 6 | AddExpr |
+| operations.rb:100:11:100:13 | ... \|\| ... | \|\| | operations.rb:100:1:100:9 | CONSTANT3 | operations.rb:100:15:100:15 | 7 | LogicalOrExpr |
+| operations.rb:101:21:101:23 | ... \|\| ... | \|\| | operations.rb:101:1:101:19 | MemberConstant | operations.rb:101:25:101:25 | 8 | LogicalOrExpr |
+| operations.rb:102:27:102:29 | ... \|\| ... | \|\| | operations.rb:102:1:102:25 | OtherConstant | operations.rb:102:31:102:31 | 7 | LogicalOrExpr |
+| operations.rb:103:13:103:15 | ... \|\| ... | \|\| | operations.rb:103:1:103:11 | CONSTANT4 | operations.rb:103:17:103:17 | 7 | LogicalOrExpr |
 binaryArithmeticOperations
 | operations.rb:32:1:32:7 | ... + ... | + | operations.rb:32:1:32:1 | w | operations.rb:32:5:32:7 | 234 | AddExpr |
 | operations.rb:33:1:33:6 | ... - ... | - | operations.rb:33:1:33:1 | x | operations.rb:33:5:33:6 | 17 | SubExpr |
@@ -56,6 +61,7 @@ binaryArithmeticOperations
 | operations.rb:89:6:89:7 | ... + ... | + | operations.rb:89:3:89:4 | @x | operations.rb:89:9:89:9 | 2 | AddExpr |
 | operations.rb:92:7:92:8 | ... / ... | / | operations.rb:92:3:92:5 | @@y | operations.rb:92:10:92:10 | 4 | DivExpr |
 | operations.rb:96:13:96:14 | ... * ... | * | operations.rb:96:1:96:11 | $global_var | operations.rb:96:16:96:16 | 6 | MulExpr |
+| operations.rb:99:11:99:12 | ... + ... | + | operations.rb:99:1:99:9 | CONSTANT2 | operations.rb:99:14:99:14 | 6 | AddExpr |
 binaryLogicalOperations
 | operations.rb:40:1:40:10 | ... && ... | && | operations.rb:40:1:40:3 | foo | operations.rb:40:8:40:10 | bar | LogicalAndExpr |
 | operations.rb:41:1:41:11 | ... and ... | and | operations.rb:41:1:41:3 | baz | operations.rb:41:9:41:11 | qux | LogicalAndExpr |
@@ -63,6 +69,10 @@ binaryLogicalOperations
 | operations.rb:43:1:43:6 | ... \|\| ... | \|\| | operations.rb:43:1:43:1 | x | operations.rb:43:6:43:6 | y | LogicalOrExpr |
 | operations.rb:77:4:77:6 | ... && ... | && | operations.rb:77:2:77:2 | x | operations.rb:77:8:77:8 | y | LogicalAndExpr |
 | operations.rb:78:4:78:6 | ... \|\| ... | \|\| | operations.rb:78:2:78:2 | a | operations.rb:78:8:78:8 | b | LogicalOrExpr |
+| operations.rb:100:11:100:13 | ... \|\| ... | \|\| | operations.rb:100:1:100:9 | CONSTANT3 | operations.rb:100:15:100:15 | 7 | LogicalOrExpr |
+| operations.rb:101:21:101:23 | ... \|\| ... | \|\| | operations.rb:101:1:101:19 | MemberConstant | operations.rb:101:25:101:25 | 8 | LogicalOrExpr |
+| operations.rb:102:27:102:29 | ... \|\| ... | \|\| | operations.rb:102:1:102:25 | OtherConstant | operations.rb:102:31:102:31 | 7 | LogicalOrExpr |
+| operations.rb:103:13:103:15 | ... \|\| ... | \|\| | operations.rb:103:1:103:11 | CONSTANT4 | operations.rb:103:17:103:17 | 7 | LogicalOrExpr |
 binaryBitwiseOperations
 | operations.rb:46:1:46:6 | ... << ... | << | operations.rb:46:1:46:1 | x | operations.rb:46:6:46:6 | 3 | LShiftExpr |
 | operations.rb:47:1:47:7 | ... >> ... | >> | operations.rb:47:1:47:1 | y | operations.rb:47:6:47:7 | 16 | RShiftExpr |
diff --git a/ruby/ql/test/library-tests/ast/operations/operation.expected b/ruby/ql/test/library-tests/ast/operations/operation.expected
index 76dbae694be..0f74eb28fb3 100644
--- a/ruby/ql/test/library-tests/ast/operations/operation.expected
+++ b/ruby/ql/test/library-tests/ast/operations/operation.expected
@@ -194,3 +194,39 @@
 | operations.rb:96:1:96:16 | ... = ... | = | operations.rb:96:13:96:14 | ... * ... | AssignExpr |
 | operations.rb:96:13:96:14 | ... * ... | * | operations.rb:96:1:96:11 | $global_var | MulExpr |
 | operations.rb:96:13:96:14 | ... * ... | * | operations.rb:96:16:96:16 | 6 | MulExpr |
+| operations.rb:98:1:98:13 | ... = ... | = | operations.rb:98:1:98:9 | CONSTANT1 | AssignExpr |
+| operations.rb:98:1:98:13 | ... = ... | = | operations.rb:98:13:98:13 | 5 | AssignExpr |
+| operations.rb:99:1:99:14 | ... += ... | += | operations.rb:99:1:99:9 | CONSTANT2 | AssignAddExpr |
+| operations.rb:99:1:99:14 | ... += ... | += | operations.rb:99:14:99:14 | 6 | AssignAddExpr |
+| operations.rb:99:1:99:14 | ... = ... | = | operations.rb:99:1:99:9 | CONSTANT2 | AssignExpr |
+| operations.rb:99:1:99:14 | ... = ... | = | operations.rb:99:11:99:12 | ... + ... | AssignExpr |
+| operations.rb:99:11:99:12 | ... + ... | + | operations.rb:99:1:99:9 | CONSTANT2 | AddExpr |
+| operations.rb:99:11:99:12 | ... + ... | + | operations.rb:99:14:99:14 | 6 | AddExpr |
+| operations.rb:100:1:100:15 | ... = ... | = | operations.rb:100:1:100:9 | CONSTANT3 | AssignExpr |
+| operations.rb:100:1:100:15 | ... = ... | = | operations.rb:100:11:100:13 | ... \|\| ... | AssignExpr |
+| operations.rb:100:1:100:15 | ... \|\|= ... | \|\|= | operations.rb:100:1:100:9 | CONSTANT3 | AssignLogicalOrExpr |
+| operations.rb:100:1:100:15 | ... \|\|= ... | \|\|= | operations.rb:100:15:100:15 | 7 | AssignLogicalOrExpr |
+| operations.rb:100:11:100:13 | ... \|\| ... | \|\| | operations.rb:100:1:100:9 | CONSTANT3 | LogicalOrExpr |
+| operations.rb:100:11:100:13 | ... \|\| ... | \|\| | operations.rb:100:15:100:15 | 7 | LogicalOrExpr |
+| operations.rb:101:1:101:3 | ... = ... | = | operations.rb:101:1:101:3 | Foo | AssignExpr |
+| operations.rb:101:1:101:3 | ... = ... | = | operations.rb:101:1:101:3 | __synth__0 | AssignExpr |
+| operations.rb:101:1:101:25 | ... = ... | = | operations.rb:101:1:101:19 | MemberConstant | AssignExpr |
+| operations.rb:101:1:101:25 | ... = ... | = | operations.rb:101:21:101:23 | ... \|\| ... | AssignExpr |
+| operations.rb:101:1:101:25 | ... \|\|= ... | \|\|= | operations.rb:101:1:101:19 | MemberConstant | AssignLogicalOrExpr |
+| operations.rb:101:1:101:25 | ... \|\|= ... | \|\|= | operations.rb:101:25:101:25 | 8 | AssignLogicalOrExpr |
+| operations.rb:101:21:101:23 | ... \|\| ... | \|\| | operations.rb:101:1:101:19 | MemberConstant | LogicalOrExpr |
+| operations.rb:101:21:101:23 | ... \|\| ... | \|\| | operations.rb:101:25:101:25 | 8 | LogicalOrExpr |
+| operations.rb:102:1:102:10 | ... = ... | = | operations.rb:102:1:102:10 | __synth__0 | AssignExpr |
+| operations.rb:102:1:102:10 | ... = ... | = | operations.rb:102:1:102:10 | call to bar | AssignExpr |
+| operations.rb:102:1:102:31 | ... = ... | = | operations.rb:102:1:102:25 | OtherConstant | AssignExpr |
+| operations.rb:102:1:102:31 | ... = ... | = | operations.rb:102:27:102:29 | ... \|\| ... | AssignExpr |
+| operations.rb:102:1:102:31 | ... \|\|= ... | \|\|= | operations.rb:102:1:102:25 | OtherConstant | AssignLogicalOrExpr |
+| operations.rb:102:1:102:31 | ... \|\|= ... | \|\|= | operations.rb:102:31:102:31 | 7 | AssignLogicalOrExpr |
+| operations.rb:102:27:102:29 | ... \|\| ... | \|\| | operations.rb:102:1:102:25 | OtherConstant | LogicalOrExpr |
+| operations.rb:102:27:102:29 | ... \|\| ... | \|\| | operations.rb:102:31:102:31 | 7 | LogicalOrExpr |
+| operations.rb:103:1:103:17 | ... = ... | = | operations.rb:103:1:103:11 | CONSTANT4 | AssignExpr |
+| operations.rb:103:1:103:17 | ... = ... | = | operations.rb:103:13:103:15 | ... \|\| ... | AssignExpr |
+| operations.rb:103:1:103:17 | ... \|\|= ... | \|\|= | operations.rb:103:1:103:11 | CONSTANT4 | AssignLogicalOrExpr |
+| operations.rb:103:1:103:17 | ... \|\|= ... | \|\|= | operations.rb:103:17:103:17 | 7 | AssignLogicalOrExpr |
+| operations.rb:103:13:103:15 | ... \|\| ... | \|\| | operations.rb:103:1:103:11 | CONSTANT4 | LogicalOrExpr |
+| operations.rb:103:13:103:15 | ... \|\| ... | \|\| | operations.rb:103:17:103:17 | 7 | LogicalOrExpr |
diff --git a/ruby/ql/test/library-tests/ast/operations/operations.rb b/ruby/ql/test/library-tests/ast/operations/operations.rb
index fcbc4551bde..86fda3c7457 100644
--- a/ruby/ql/test/library-tests/ast/operations/operations.rb
+++ b/ruby/ql/test/library-tests/ast/operations/operations.rb
@@ -94,3 +94,10 @@ end
 
 $global_var = 5
 $global_var *= 6
+
+CONSTANT1 = 5
+CONSTANT2 += 6
+CONSTANT3 ||= 7
+Foo::MemberConstant ||= 8
+foo(1).bar::OtherConstant ||= 7
+::CONSTANT4 ||= 7
diff --git a/ruby/ql/test/library-tests/controlflow/graph/Cfg.expected b/ruby/ql/test/library-tests/controlflow/graph/Cfg.expected
index 2359eb2c24a..9c26785029e 100644
--- a/ruby/ql/test/library-tests/controlflow/graph/Cfg.expected
+++ b/ruby/ql/test/library-tests/controlflow/graph/Cfg.expected
@@ -3762,6 +3762,81 @@ cfg.rb:
 #  215| self
 #-----|  -> call to something_else
 
+constant_compound_assign.rb:
+#    1| Foo
+#-----|  -> foo_before
+
+#    1| enter constant_compound_assign.rb
+#-----|  -> Foo
+
+#    1| exit constant_compound_assign.rb
+
+#    1| exit constant_compound_assign.rb (normal)
+#-----|  -> exit constant_compound_assign.rb
+
+#    2| foo_before
+#-----|  -> FOO_CONSTANT
+
+#    5| FOO_CONSTANT
+#-----|  -> FOO_CONSTANT
+
+#    5| FOO_CONSTANT
+#-----| true -> ... || ...
+#-----| false -> 123
+
+#    5| ... = ...
+#-----|  -> foo_after
+
+#    5| ... || ...
+#-----|  -> ... = ...
+
+#    5| 123
+#-----|  -> ... || ...
+
+#    7| foo_after
+#-----|  -> top_before
+
+#   11| top_before
+#-----|  -> TOP_CONSTANT
+
+#   14| TOP_CONSTANT
+#-----|  -> TOP_CONSTANT
+
+#   14| TOP_CONSTANT
+#-----| true -> ... || ...
+#-----| false -> 123
+
+#   14| ... = ...
+#-----|  -> top_after
+
+#   14| ... || ...
+#-----|  -> ... = ...
+
+#   14| 123
+#-----|  -> ... || ...
+
+#   16| top_after
+#-----|  -> TOP_CONSTANT2
+
+#   19| TOP_CONSTANT2
+#-----|  -> TOP_CONSTANT2
+
+#   19| TOP_CONSTANT2
+#-----| true -> ... || ...
+#-----| false -> 123
+
+#   19| ... = ...
+#-----|  -> top_after2
+
+#   19| ... || ...
+#-----|  -> ... = ...
+
+#   19| 123
+#-----|  -> ... || ...
+
+#   21| top_after2
+#-----|  -> exit constant_compound_assign.rb (normal)
+
 desugar.rb:
 #    1| enter m1
 #-----|  -> x
diff --git a/ruby/ql/test/library-tests/controlflow/graph/Nodes.expected b/ruby/ql/test/library-tests/controlflow/graph/Nodes.expected
index b929f1fe965..b17584ce259 100644
--- a/ruby/ql/test/library-tests/controlflow/graph/Nodes.expected
+++ b/ruby/ql/test/library-tests/controlflow/graph/Nodes.expected
@@ -212,6 +212,9 @@ positionalArguments
 | cfg.rb:205:1:205:23 | call to bar | cfg.rb:205:10:205:10 | 1 |
 | cfg.rb:205:1:205:23 | call to bar | cfg.rb:205:12:205:12 | 2 |
 | cfg.rb:205:4:205:5 | call to == | cfg.rb:205:1:205:3 | __synth__0__1 |
+| constant_compound_assign.rb:5:18:5:20 | ... \|\| ... | constant_compound_assign.rb:5:22:5:24 | 123 |
+| constant_compound_assign.rb:14:14:14:16 | ... \|\| ... | constant_compound_assign.rb:14:18:14:20 | 123 |
+| constant_compound_assign.rb:19:17:19:19 | ... \|\| ... | constant_compound_assign.rb:19:21:19:23 | 123 |
 | desugar.rb:2:5:2:6 | ... + ... | desugar.rb:2:8:2:8 | 1 |
 | desugar.rb:6:3:6:13 | call to count= | desugar.rb:6:17:6:17 | ... = ... |
 | desugar.rb:10:3:10:10 | call to []= | desugar.rb:10:9:10:9 | 0 |
diff --git a/ruby/ql/test/library-tests/controlflow/graph/constant_compound_assign.rb b/ruby/ql/test/library-tests/controlflow/graph/constant_compound_assign.rb
new file mode 100644
index 00000000000..178dbbf1797
--- /dev/null
+++ b/ruby/ql/test/library-tests/controlflow/graph/constant_compound_assign.rb
@@ -0,0 +1,22 @@
+module Foo
+    def foo_before
+    end
+
+    FOO_CONSTANT ||= 123
+
+    def foo_after
+    end
+end
+
+def top_before
+end
+
+TOP_CONSTANT ||= 123
+
+def top_after
+end
+
+::TOP_CONSTANT2 ||= 123
+
+def top_after2
+end