diff --git a/postgraphile/postgraphile/__tests__/kitchen-sink-schema.sql b/postgraphile/postgraphile/__tests__/kitchen-sink-schema.sql
index 23f66951c3..836e91f426 100644
--- a/postgraphile/postgraphile/__tests__/kitchen-sink-schema.sql
+++ b/postgraphile/postgraphile/__tests__/kitchen-sink-schema.sql
@@ -259,6 +259,7 @@ create table c.edge_case (
 alter table c.edge_case drop column drop_me;
 
 create function c.edge_case_computed(edge_case c.edge_case) returns text as $$ select 'hello world'::text $$ language sql stable;
+comment on function c.edge_case_computed is E'@sortable';
 
 create domain a.an_int as integer;
 create domain b.another_int as a.an_int;
diff --git a/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.json5 b/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.json5
new file mode 100644
index 0000000000..c12c4bfc9c
--- /dev/null
+++ b/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.json5
@@ -0,0 +1,26 @@
+{
+  allEdgeCases: {
+    nodes: [
+      {
+        computed: "hello world",
+        wontCastEasy: 20,
+        rowId: 1,
+      },
+      {
+        computed: "hello world",
+        wontCastEasy: null,
+        rowId: 2,
+      },
+      {
+        computed: "hello world",
+        wontCastEasy: -512,
+        rowId: 3,
+      },
+      {
+        computed: "hello world",
+        wontCastEasy: null,
+        rowId: 4,
+      },
+    ],
+  },
+}
diff --git a/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.mermaid b/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.mermaid
new file mode 100644
index 0000000000..1e4c33a14f
--- /dev/null
+++ b/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.mermaid
@@ -0,0 +1,54 @@
+%%{init: {'themeVariables': { 'fontSize': '12px'}}}%%
+graph TD
+    classDef path fill:#eee,stroke:#000,color:#000
+    classDef plan fill:#fff,stroke-width:1px,color:#000
+    classDef itemplan fill:#fff,stroke-width:2px,color:#000
+    classDef unbatchedplan fill:#dff,stroke-width:1px,color:#000
+    classDef sideeffectplan fill:#fcc,stroke-width:2px,color:#000
+    classDef bucket fill:#f6f6f6,color:#000,stroke-width:2px,text-align:left
+
+
+    %% plan dependencies
+    Object11{{"Object[11∈0] ➊<br />ᐸ{pgSettings,withPgClient}ᐳ"}}:::plan
+    Access9{{"Access[9∈0] ➊<br />ᐸ2.pgSettingsᐳ"}}:::plan
+    Access10{{"Access[10∈0] ➊<br />ᐸ2.withPgClientᐳ"}}:::plan
+    Access9 & Access10 --> Object11
+    __Value2["__Value[2∈0] ➊<br />ᐸcontextᐳ"]:::plan
+    __Value2 --> Access9
+    __Value2 --> Access10
+    __Value4["__Value[4∈0] ➊<br />ᐸrootValueᐳ"]:::plan
+    Connection12{{"Connection[12∈0] ➊<br />ᐸ8ᐳ"}}:::plan
+    PgSelect14[["PgSelect[14∈1] ➊<br />ᐸedge_caseᐳ"]]:::plan
+    Object11 & Connection12 --> PgSelect14
+    PgSelectRows15[["PgSelectRows[15∈1] ➊"]]:::plan
+    PgSelect14 --> PgSelectRows15
+    __Item16[/"__Item[16∈2]<br />ᐸ15ᐳ"\]:::itemplan
+    PgSelectRows15 ==> __Item16
+    PgSelectSingle17{{"PgSelectSingle[17∈2]<br />ᐸedge_caseᐳ"}}:::plan
+    __Item16 --> PgSelectSingle17
+    PgClassExpression19{{"PgClassExpression[19∈3]<br />ᐸ”c”.”edge_...ge_case__)ᐳ"}}:::plan
+    PgSelectSingle17 --> PgClassExpression19
+    PgClassExpression20{{"PgClassExpression[20∈3]<br />ᐸ__edge_cas...cast_easy”ᐳ"}}:::plan
+    PgSelectSingle17 --> PgClassExpression20
+    PgClassExpression21{{"PgClassExpression[21∈3]<br />ᐸ__edge_case__.”row_id”ᐳ"}}:::plan
+    PgSelectSingle17 --> PgClassExpression21
+
+    %% define steps
+
+    subgraph "Buckets for queries/v4/orderby-computed"
+    Bucket0("Bucket 0 (root)"):::bucket
+    classDef bucket0 stroke:#696969
+    class Bucket0,__Value2,__Value4,Access9,Access10,Object11,Connection12 bucket0
+    Bucket1("Bucket 1 (nullableBoundary)<br />Deps: 11, 12<br /><br />ROOT Connectionᐸ8ᐳ[12]<br />1: PgSelect[14]<br />2: PgSelectRows[15]"):::bucket
+    classDef bucket1 stroke:#00bfff
+    class Bucket1,PgSelect14,PgSelectRows15 bucket1
+    Bucket2("Bucket 2 (listItem)<br /><br />ROOT __Item{2}ᐸ15ᐳ[16]"):::bucket
+    classDef bucket2 stroke:#7f007f
+    class Bucket2,__Item16,PgSelectSingle17 bucket2
+    Bucket3("Bucket 3 (nullableBoundary)<br />Deps: 17<br /><br />ROOT PgSelectSingle{2}ᐸedge_caseᐳ[17]"):::bucket
+    classDef bucket3 stroke:#ffa500
+    class Bucket3,PgClassExpression19,PgClassExpression20,PgClassExpression21 bucket3
+    Bucket0 --> Bucket1
+    Bucket1 --> Bucket2
+    Bucket2 --> Bucket3
+    end
diff --git a/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.sql b/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.sql
new file mode 100644
index 0000000000..d1b70920b5
--- /dev/null
+++ b/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.sql
@@ -0,0 +1,7 @@
+select
+  "c"."edge_case_computed"(__edge_case__) as "0",
+  __edge_case__."wont_cast_easy"::text as "1",
+  __edge_case__."row_id"::text as "2",
+  __edge_case__."not_null_has_default"::text as "3"
+from "c"."edge_case" as __edge_case__
+order by "c"."edge_case_computed"(__edge_case__) asc;
\ No newline at end of file
diff --git a/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.test.graphql b/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.test.graphql
new file mode 100644
index 0000000000..1cbd72c852
--- /dev/null
+++ b/postgraphile/postgraphile/__tests__/queries/v4/orderby-computed.test.graphql
@@ -0,0 +1,11 @@
+## expect(errors).toBeFalsy();
+#> schema: ["a", "b", "c"]
+{
+  allEdgeCases(orderBy: COMPUTED_ASC) {
+    nodes {
+      computed
+      wontCastEasy
+      rowId
+    }
+  }
+}
\ No newline at end of file