diff --git a/pkg/report/model.go b/pkg/report/model.go
index a224e24d1..fe0872a48 100644
--- a/pkg/report/model.go
+++ b/pkg/report/model.go
@@ -34,6 +34,8 @@ type (
 
 	StepDefinitionSet []*StepDefinition
 	StepDefinition    struct {
+		Kind string `json:"kind,omitempty"`
+
 		Load  *LoadStepDefinition  `json:"load,omitempty"`
 		Join  *JoinStepDefinition  `json:"join,omitempty"`
 		Group *GroupStepDefinition `json:"group,omitempty"`
diff --git a/system/types/report.go b/system/types/report.go
index c82ebd208..724dfc426 100644
--- a/system/types/report.go
+++ b/system/types/report.go
@@ -32,16 +32,11 @@ type (
 	}
 
 	ReportDataSource struct {
-		Name   string `json:"name,omitempty"`
-		Groups []*ReportStepGroup
+		Meta interface{}            `json:"meta,omitempty"`
+		Step *report.StepDefinition `json:"step"`
 	}
 	ReportDataSourceSet []*ReportDataSource
 
-	ReportStepGroup struct {
-		Name  string                   `json:"name,omitempty"`
-		Steps report.StepDefinitionSet `json:"steps"`
-	}
-
 	ReportMeta struct {
 		Name        string `json:"name"`
 		Description string `json:"description"`
@@ -87,9 +82,7 @@ func (ss ReportDataSourceSet) ModelSteps() report.StepDefinitionSet {
 	out := make(report.StepDefinitionSet, 0, 124)
 
 	for _, s := range ss {
-		for _, g := range s.Groups {
-			out = append(out, g.Steps...)
-		}
+		out = append(out, s.Step)
 	}
 
 	return out
diff --git a/tests/reporter/testdata/S0001_describe_basic/report.json b/tests/reporter/testdata/S0001_describe_basic/report.json
index 7f60f358a..5f2f8f83d 100644
--- a/tests/reporter/testdata/S0001_describe_basic/report.json
+++ b/tests/reporter/testdata/S0001_describe_basic/report.json
@@ -1,38 +1,29 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-          { "load": {
-            "name": "jobs",
-            "source": "composeRecords",
-            "definition": {
-              "module": "job",
-              "namespace": "ns"
-            }
-          }},
-
-          { "join": {
-            "name": "joined",
-            "localSource": "users",
-            "localColumn": "join_key",
-            "foreignSource": "jobs",
-            "foreignColumn": "usr"
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+    { "step": { "load": {
+      "name": "jobs",
+      "source": "composeRecords",
+      "definition": {
+        "module": "job",
+        "namespace": "ns"
+      }
+    }}},
+    { "step": { "join": {
+      "name": "joined",
+      "localSource": "users",
+      "localColumn": "join_key",
+      "foreignSource": "jobs",
+      "foreignColumn": "usr"
+    }}}
+  ],
   "describe": ["users", "jobs", "joined"]
 }
diff --git a/tests/reporter/testdata/S1001_loading_basic/report.json b/tests/reporter/testdata/S1001_loading_basic/report.json
index 47ccafd2e..26f4dd6b5 100644
--- a/tests/reporter/testdata/S1001_loading_basic/report.json
+++ b/tests/reporter/testdata/S1001_loading_basic/report.json
@@ -1,23 +1,14 @@
 {
   "handle": "testing_report",
   "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }}
-        ]
+    "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+  }}}],
   "frames": [{
     "name":   "result",
     "source": "users",
diff --git a/tests/reporter/testdata/S1002_loading_filtering/report.json b/tests/reporter/testdata/S1002_loading_filtering/report.json
index 5271b08bd..76d7180b8 100644
--- a/tests/reporter/testdata/S1002_loading_filtering/report.json
+++ b/tests/reporter/testdata/S1002_loading_filtering/report.json
@@ -1,23 +1,14 @@
 {
   "handle": "testing_report",
   "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }}
-        ]
+    "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+  }}}],
   "frames": [{
     "name":   "result",
     "source": "users",
diff --git a/tests/reporter/testdata/S1003_loading_sorting/report.json b/tests/reporter/testdata/S1003_loading_sorting/report.json
index aa111be3e..89217b659 100644
--- a/tests/reporter/testdata/S1003_loading_sorting/report.json
+++ b/tests/reporter/testdata/S1003_loading_sorting/report.json
@@ -1,23 +1,14 @@
 {
   "handle": "testing_report",
   "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }}
-        ]
+    "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+  }}}],
   "frames": [{
     "name":   "result",
     "source": "users",
diff --git a/tests/reporter/testdata/S1004_loading_paging/report.json b/tests/reporter/testdata/S1004_loading_paging/report.json
index f5bab2d71..081ab4655 100644
--- a/tests/reporter/testdata/S1004_loading_paging/report.json
+++ b/tests/reporter/testdata/S1004_loading_paging/report.json
@@ -1,23 +1,14 @@
 {
   "handle": "testing_report",
   "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }}
-        ]
+    "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+  }}}],
   "frames": [{
     "name":   "result",
     "source": "users",
diff --git a/tests/reporter/testdata/S2001_grouping_basic/report.json b/tests/reporter/testdata/S2001_grouping_basic/report.json
index 57ca0c713..2d7286f59 100644
--- a/tests/reporter/testdata/S2001_grouping_basic/report.json
+++ b/tests/reporter/testdata/S2001_grouping_basic/report.json
@@ -1,35 +1,27 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-
-          { "group": {
-            "name": "grouped",
-            "source": "users",
-            "keys": [
-              { "name": "by_name", "column": "first_name" }
-            ],
-            "columns": [
-              { "name": "count", "aggregate": "count" },
-              { "name": "total", "aggregate": "sum", "column": "number_of_numbers" }
-            ]
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+
+    { "step": { "group": {
+      "name": "grouped",
+      "source": "users",
+      "keys": [
+        { "name": "by_name", "column": "first_name" }
+      ],
+      "columns": [
+        { "name": "count", "aggregate": "count" },
+        { "name": "total", "aggregate": "sum", "column": "number_of_numbers" }
+      ]
+    }}}
+  ],
   "frames": [{
     "name":   "result",
     "source": "grouped",
diff --git a/tests/reporter/testdata/S2002_grouping_filtering/report.json b/tests/reporter/testdata/S2002_grouping_filtering/report.json
index ec881ff7a..74a7ac5fb 100644
--- a/tests/reporter/testdata/S2002_grouping_filtering/report.json
+++ b/tests/reporter/testdata/S2002_grouping_filtering/report.json
@@ -1,35 +1,27 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-
-          { "group": {
-            "name": "grouped",
-            "source": "users",
-            "keys": [
-              { "name": "by_name", "column": "first_name" }
-            ],
-            "columns": [
-              { "name": "count", "aggregate": "count" },
-              { "name": "total", "aggregate": "sum", "column": "number_of_numbers" }
-            ]
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+
+    { "step": { "group": {
+      "name": "grouped",
+      "source": "users",
+      "keys": [
+        { "name": "by_name", "column": "first_name" }
+      ],
+      "columns": [
+        { "name": "count", "aggregate": "count" },
+        { "name": "total", "aggregate": "sum", "column": "number_of_numbers" }
+      ]
+    }}}
+  ],
   "frames": [{
     "name":   "result",
     "source": "grouped",
diff --git a/tests/reporter/testdata/S2003_grouping_sorting/report.json b/tests/reporter/testdata/S2003_grouping_sorting/report.json
index d520e8fe3..56f21550f 100644
--- a/tests/reporter/testdata/S2003_grouping_sorting/report.json
+++ b/tests/reporter/testdata/S2003_grouping_sorting/report.json
@@ -1,35 +1,27 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-
-          { "group": {
-            "name": "grouped",
-            "source": "users",
-            "keys": [
-              { "name": "by_name", "column": "first_name" }
-            ],
-            "columns": [
-              { "name": "count", "aggregate": "count" },
-              { "name": "total", "aggregate": "sum", "column": "number_of_numbers" }
-            ]
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+
+    { "step": { "group": {
+      "name": "grouped",
+      "source": "users",
+      "keys": [
+        { "name": "by_name", "column": "first_name" }
+      ],
+      "columns": [
+        { "name": "count", "aggregate": "count" },
+        { "name": "total", "aggregate": "sum", "column": "number_of_numbers" }
+      ]
+    }}}
+  ],
   "frames": [{
     "name":   "result",
     "source": "grouped",
diff --git a/tests/reporter/testdata/S2004_grouping_paging/report.json b/tests/reporter/testdata/S2004_grouping_paging/report.json
index d99bcec09..7bd68d2b3 100644
--- a/tests/reporter/testdata/S2004_grouping_paging/report.json
+++ b/tests/reporter/testdata/S2004_grouping_paging/report.json
@@ -1,35 +1,27 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-
-          { "group": {
-            "name": "grouped",
-            "source": "users",
-            "keys": [
-              { "name": "by_name", "column": "first_name" }
-            ],
-            "columns": [
-              { "name": "count", "aggregate": "count" },
-              { "name": "total", "aggregate": "sum", "column": "number_of_numbers" }
-            ]
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+
+    { "step": { "group": {
+      "name": "grouped",
+      "source": "users",
+      "keys": [
+        { "name": "by_name", "column": "first_name" }
+      ],
+      "columns": [
+        { "name": "count", "aggregate": "count" },
+        { "name": "total", "aggregate": "sum", "column": "number_of_numbers" }
+      ]
+    }}}
+  ],
   "frames": [{
     "name":   "result",
     "source": "grouped",
diff --git a/tests/reporter/testdata/S3001_joining_basic/report.json b/tests/reporter/testdata/S3001_joining_basic/report.json
index fc8c483dd..48a0c4054 100644
--- a/tests/reporter/testdata/S3001_joining_basic/report.json
+++ b/tests/reporter/testdata/S3001_joining_basic/report.json
@@ -1,39 +1,30 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-          { "load": {
-            "name": "jobs",
-            "source": "composeRecords",
-            "definition": {
-              "module": "job",
-              "namespace": "ns"
-            }
-          }},
-
-          { "join": {
-            "name": "joined",
-            "localSource": "users",
-            "localColumn": "join_key",
-            "foreignSource": "jobs",
-            "foreignColumn": "usr"
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+    { "step": { "load": {
+      "name": "jobs",
+      "source": "composeRecords",
+      "definition": {
+        "module": "job",
+        "namespace": "ns"
+      }
+    }}},
+    { "step": { "join": {
+      "name": "joined",
+      "localSource": "users",
+      "localColumn": "join_key",
+      "foreignSource": "jobs",
+      "foreignColumn": "usr"
+    }}}
+  ],
   "frames": [{
     "name":   "result",
     "source": "joined",
diff --git a/tests/reporter/testdata/S3002_joining_filtering/report.json b/tests/reporter/testdata/S3002_joining_filtering/report.json
index c6dd5a1c2..d1651f566 100644
--- a/tests/reporter/testdata/S3002_joining_filtering/report.json
+++ b/tests/reporter/testdata/S3002_joining_filtering/report.json
@@ -1,39 +1,30 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-          { "load": {
-            "name": "jobs",
-            "source": "composeRecords",
-            "definition": {
-              "module": "job",
-              "namespace": "ns"
-            }
-          }},
-
-          { "join": {
-            "name": "joined",
-            "localSource": "users",
-            "localColumn": "join_key",
-            "foreignSource": "jobs",
-            "foreignColumn": "usr"
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+    { "step": { "load": {
+      "name": "jobs",
+      "source": "composeRecords",
+      "definition": {
+        "module": "job",
+        "namespace": "ns"
+      }
+    }}},
+    { "step": { "join": {
+      "name": "joined",
+      "localSource": "users",
+      "localColumn": "join_key",
+      "foreignSource": "jobs",
+      "foreignColumn": "usr"
+    }}}
+  ],
   "frames": [{
     "name":   "result",
     "source": "joined",
diff --git a/tests/reporter/testdata/S3003_joining_sorting_local/report.json b/tests/reporter/testdata/S3003_joining_sorting_local/report.json
index f65974699..cf08a1eba 100644
--- a/tests/reporter/testdata/S3003_joining_sorting_local/report.json
+++ b/tests/reporter/testdata/S3003_joining_sorting_local/report.json
@@ -1,39 +1,30 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-          { "load": {
-            "name": "jobs",
-            "source": "composeRecords",
-            "definition": {
-              "module": "job",
-              "namespace": "ns"
-            }
-          }},
-
-          { "join": {
-            "name": "joined",
-            "localSource": "users",
-            "localColumn": "join_key",
-            "foreignSource": "jobs",
-            "foreignColumn": "usr"
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+    { "step": { "load": {
+      "name": "jobs",
+      "source": "composeRecords",
+      "definition": {
+        "module": "job",
+        "namespace": "ns"
+      }
+    }}},
+    { "step": { "join": {
+      "name": "joined",
+      "localSource": "users",
+      "localColumn": "join_key",
+      "foreignSource": "jobs",
+      "foreignColumn": "usr"
+    }}}
+  ],
   "frames": [{
     "name":   "result",
     "source": "joined",
diff --git a/tests/reporter/testdata/S3004_joining_sorting_foreign/report.json b/tests/reporter/testdata/S3004_joining_sorting_foreign/report.json
index 9f3a7bcbf..b3fd1040d 100644
--- a/tests/reporter/testdata/S3004_joining_sorting_foreign/report.json
+++ b/tests/reporter/testdata/S3004_joining_sorting_foreign/report.json
@@ -1,39 +1,30 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-          { "load": {
-            "name": "jobs",
-            "source": "composeRecords",
-            "definition": {
-              "module": "job",
-              "namespace": "ns"
-            }
-          }},
-
-          { "join": {
-            "name": "joined",
-            "localSource": "users",
-            "localColumn": "join_key",
-            "foreignSource": "jobs",
-            "foreignColumn": "usr"
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+    { "step": { "load": {
+      "name": "jobs",
+      "source": "composeRecords",
+      "definition": {
+        "module": "job",
+        "namespace": "ns"
+      }
+    }}},
+    { "step": { "join": {
+      "name": "joined",
+      "localSource": "users",
+      "localColumn": "join_key",
+      "foreignSource": "jobs",
+      "foreignColumn": "usr"
+    }}}
+  ],
   "frames": [{
     "name":   "result",
     "source": "joined",
diff --git a/tests/reporter/testdata/S3005_joining_paging/report.json b/tests/reporter/testdata/S3005_joining_paging/report.json
index e6aa52ebd..8d0574356 100644
--- a/tests/reporter/testdata/S3005_joining_paging/report.json
+++ b/tests/reporter/testdata/S3005_joining_paging/report.json
@@ -1,39 +1,30 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-          { "load": {
-            "name": "jobs",
-            "source": "composeRecords",
-            "definition": {
-              "module": "job",
-              "namespace": "ns"
-            }
-          }},
-
-          { "join": {
-            "name": "joined",
-            "localSource": "users",
-            "localColumn": "join_key",
-            "foreignSource": "jobs",
-            "foreignColumn": "usr"
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+    { "step": { "load": {
+      "name": "jobs",
+      "source": "composeRecords",
+      "definition": {
+        "module": "job",
+        "namespace": "ns"
+      }
+    }}},
+    { "step": { "join": {
+      "name": "joined",
+      "localSource": "users",
+      "localColumn": "join_key",
+      "foreignSource": "jobs",
+      "foreignColumn": "usr"
+    }}}
+  ],
   "frames": [{
     "name":   "result",
     "source": "joined",
diff --git a/tests/reporter/testdata/S7001_modeling_multi/report.json b/tests/reporter/testdata/S7001_modeling_multi/report.json
index 4dfa397c9..9e3024481 100644
--- a/tests/reporter/testdata/S7001_modeling_multi/report.json
+++ b/tests/reporter/testdata/S7001_modeling_multi/report.json
@@ -1,35 +1,27 @@
 {
   "handle": "testing_report",
-  "sources": [{
-    "name": "unnamed_src",
-    "groups": [
-      {
-        "name": "unnamed_grp",
-        "steps": [
-          { "load": {
-            "name": "users",
-            "source": "composeRecords",
-            "definition": {
-              "module": "user",
-              "namespace": "ns"
-            }
-          }},
-
-          { "group": {
-            "name": "grouped",
-            "source": "users",
-            "keys": [
-              { "name": "by_name", "column": "first_name" }
-            ],
-            "columns": [
-              { "name": "count", "aggregate": "count" },
-              { "name": "total", "aggregate": "sum", "column": "number_of_numbers" }
-            ]
-          }}
-        ]
+  "sources": [
+    { "step": { "load": {
+      "name": "users",
+      "source": "composeRecords",
+      "definition": {
+        "module": "user",
+        "namespace": "ns"
       }
-    ]
-  }],
+    }}},
+
+    { "step": { "group": {
+      "name": "grouped",
+      "source": "users",
+      "keys": [
+        { "name": "by_name", "column": "first_name" }
+      ],
+      "columns": [
+        { "name": "count", "aggregate": "count" },
+        { "name": "total", "aggregate": "sum", "column": "number_of_numbers" }
+      ]
+    }}}
+  ],
   "frames": [{
     "name":   "base",
     "source": "users",