diff --git a/lib/gc_index_relay/nostr/publication_search.ex b/lib/gc_index_relay/nostr/publication_search.ex
new file mode 100644
index 0000000..9e219a4
--- /dev/null
+++ b/lib/gc_index_relay/nostr/publication_search.ex
@@ -0,0 +1,150 @@
+defmodule GcIndexRelay.Nostr.PublicationSearch do
+  @moduledoc """
+  Exact-match search over kind **30040** publication index metadata (`d`, `title`, `author`, `source`).
+
+  Matches jumble's `publicationFieldExactMatch/2` normalization (case-insensitive, hyphen/space).
+  """
+
+  import Ecto.Query, warn: false
+
+  alias GcIndexRelay.Nostr.Event
+  alias GcIndexRelay.Nostr.PubEvent
+  alias GcIndexRelay.Nostr.Tag
+  alias GcIndexRelay.Repo
+
+  @publication_kind 30_040
+  @search_tag_names ~w(d title author source)
+
+  @doc """
+  Search kind-30040 events by exact metadata match. Returns newest first.
+  """
+  @spec search(String.t(), keyword()) :: {:ok, [PubEvent.t()]} | {:error, String.t()}
+  def search(query, opts \\ []) when is_binary(query) do
+    needles = query_needles(query)
+
+    if needles == [] do
+      {:ok, []}
+    else
+      limit = opts |> Keyword.get(:limit, 25) |> clamp_limit()
+      do_search(needles, limit)
+    end
+  end
+
+  defp clamp_limit(limit) when is_integer(limit), do: limit |> max(1) |> min(100)
+  defp clamp_limit(_), do: 25
+
+  defp do_search(needles, limit) do
+    spaced_needles = Enum.map(needles, &spaced_form/1) |> Enum.uniq()
+
+    tag_match =
+      Enum.reduce(needles, dynamic(false), fn needle, acc ->
+        spaced = spaced_form(needle)
+
+        dynamic(
+          [t],
+          ^acc or
+            fragment("LOWER(TRIM(?)) = ?", t.value, ^needle) or
+            fragment("LOWER(TRIM(REPLACE(?, '-', ' '))) = ?", t.value, ^spaced)
+        )
+      end)
+
+    # Also match when the stored value's spaced form equals any spaced needle.
+    tag_match =
+      Enum.reduce(spaced_needles, tag_match, fn spaced, acc ->
+        dynamic(
+          [t],
+          ^acc or fragment("LOWER(TRIM(REPLACE(?, '-', ' '))) = ?", t.value, ^spaced)
+        )
+      end)
+
+    event_ids =
+      from(t in Tag,
+        inner_join: e in Event,
+        on: t.event_id == e.id,
+        where: e.kind == ^@publication_kind,
+        where: t.name in ^@search_tag_names,
+        where: ^tag_match,
+        distinct: e.id,
+        order_by: [desc: e.created_at],
+        limit: ^limit,
+        select: e.id
+      )
+      |> Repo.all()
+
+    events =
+      from(e in Event,
+        where: e.id in ^event_ids,
+        order_by: [desc: e.created_at],
+        preload: [:tags]
+      )
+      |> Repo.all()
+
+    pub_events_from_db(events)
+  end
+
+  defp pub_events_from_db(events) do
+    Enum.reduce_while(events, {:ok, []}, fn event, {:ok, acc} ->
+      case PubEvent.from_db(event) do
+        {:ok, pub_event} -> {:cont, {:ok, [pub_event | acc]}}
+        {:error, _} = err -> {:halt, err}
+      end
+    end)
+    |> case do
+      {:ok, list} -> {:ok, Enum.reverse(list)}
+      {:error, _} = err -> err
+    end
+  end
+
+  @doc false
+  def query_needles(query) do
+    query
+    |> strip_quotes()
+    |> String.trim()
+    |> case do
+      "" ->
+        []
+
+      raw ->
+        lower = String.downcase(raw)
+        normalized = lower |> String.replace(~r/\s+/, " ") |> String.trim()
+
+        hyphen =
+          lower
+          |> String.replace(~r/\s+/, "-")
+          |> String.replace(~r/-+/, "-")
+          |> String.trim("-")
+
+        [lower, normalized, hyphen]
+        |> Enum.reject(&(&1 == ""))
+        |> Enum.uniq()
+    end
+  end
+
+  defp strip_quotes(raw) do
+    trimmed = String.trim(raw)
+
+    pairs = [
+      {"\"", "\""},
+      {"'", "'"},
+      {"“", "”"},
+      {"‘", "’"}
+    ]
+
+    Enum.reduce(pairs, trimmed, fn {open, close}, acc ->
+      if String.length(acc) >= 2 and String.starts_with?(acc, open) and
+           String.ends_with?(acc, close) do
+        acc |> String.slice(1..-2//1) |> String.trim()
+      else
+        acc
+      end
+    end)
+  end
+
+  defp spaced_form(value) do
+    value
+    |> String.downcase()
+    |> String.replace("-", " ")
+    |> String.replace(~r/\s+/, " ")
+    |> String.trim()
+  end
+end
diff --git a/lib/gc_index_relay_web/controllers/api_controller.ex b/lib/gc_index_relay_web/controllers/api_controller.ex
index 1532d61..351e57e 100644
--- a/lib/gc_index_relay_web/controllers/api_controller.ex
+++ b/lib/gc_index_relay_web/controllers/api_controller.ex
@@ -19,6 +19,11 @@ defmodule GcIndexRelayWeb.ApiController do
           path: "/api/events/filter",
           description: "Query events with a NIP-01 filter body"
         },
+        %{
+          method: "POST",
+          path: "/api/publications/search",
+          description: "Exact metadata search for kind-30040 publication indexes"
+        },
         %{method: "GET", path: "/api/events/:id", description: "Get a single event by ID"},
         %{method: "POST", path: "/api/events", description: "Publish a new event"},
         %{method: "DELETE", path: "/api/events/:id", description: "Delete an event by ID"},
diff --git a/lib/gc_index_relay_web/controllers/page_html/home.html.heex b/lib/gc_index_relay_web/controllers/page_html/home.html.heex
index 368818c..4d40d6d 100644
--- a/lib/gc_index_relay_web/controllers/page_html/home.html.heex
+++ b/lib/gc_index_relay_web/controllers/page_html/home.html.heex
@@ -65,6 +65,7 @@
         {"GET",    "/api",               "List available endpoints"},
         {"GET",    "/api/events",         "Cacheable query (since, until, limit)"},
         {"POST",   "/api/events/filter",  "Filter query with JSON body"},
+        {"POST",   "/api/publications/search", "Publication metadata search (kind 30040)"},
         {"GET",    "/api/events/:id",     "Fetch a single event by ID"},
         {"POST",   "/api/events",         "Publish a new event"},
         {"DELETE", "/api/events/:id",     "Delete an event by ID"},
diff --git a/lib/gc_index_relay_web/controllers/publication_search_controller.ex b/lib/gc_index_relay_web/controllers/publication_search_controller.ex
new file mode 100644
index 0000000..18830d1
--- /dev/null
+++ b/lib/gc_index_relay_web/controllers/publication_search_controller.ex
@@ -0,0 +1,57 @@
+defmodule GcIndexRelayWeb.PublicationSearchController do
+  use GcIndexRelayWeb, :controller
+  use PhoenixSwagger
+
+  alias GcIndexRelay.Nostr.PublicationSearch
+
+  action_fallback GcIndexRelayWeb.FallbackController
+
+  swagger_path :search do
+    post("/api/publications/search")
+    summary("Search kind-30040 publication indexes by metadata")
+
+    description("""
+    Exact-match search over publication index metadata tags: `d`, `title`, `author`, and `source`.
+    Matching is case-insensitive and treats hyphens and spaces as equivalent. Partial substring
+    matches are not returned.
+    """)
+
+    tag("Publications")
+    operation_id("search_publications")
+    response(200, "OK", Schema.ref(:PubEventList))
+    response(400, "Bad Request")
+  end
+
+  @doc """
+  POST /api/publications/search — exact metadata search for kind-30040 publication indexes.
+  """
+  def search(conn, params) do
+    with {:ok, query} <- fetch_query(params),
+         {:ok, limit} <- parse_limit(Map.get(params, "limit", 25)),
+         :ok <- validate_limit(limit),
+         {:ok, events} <- PublicationSearch.search(query, limit: limit) do
+      render(conn, :index, events: events)
+    end
+  end
+
+  defp fetch_query(%{"q" => q}) when is_binary(q) do
+    trimmed = String.trim(q)
+    if trimmed == "", do: {:error, "Query q must not be empty."}, else: {:ok, trimmed}
+  end
+
+  defp fetch_query(_), do: {:error, "Missing required field: q"}
+
+  defp parse_limit(v) when is_integer(v), do: {:ok, v}
+
+  defp parse_limit(v) when is_binary(v) do
+    case Integer.parse(v) do
+      {int, ""} -> {:ok, int}
+      _ -> {:error, "Invalid limit: must be an integer between 1 and 100"}
+    end
+  end
+
+  defp parse_limit(_), do: {:error, "Invalid limit: must be an integer between 1 and 100"}
+
+  defp validate_limit(limit) when is_integer(limit) and limit >= 1 and limit <= 100, do: :ok
+  defp validate_limit(_), do: {:error, "The limit must be between 1 and 100."}
+end
diff --git a/lib/gc_index_relay_web/controllers/publication_search_json.ex b/lib/gc_index_relay_web/controllers/publication_search_json.ex
new file mode 100644
index 0000000..4cd1b9d
--- /dev/null
+++ b/lib/gc_index_relay_web/controllers/publication_search_json.ex
@@ -0,0 +1,19 @@
+defmodule GcIndexRelayWeb.PublicationSearchJSON do
+  alias GcIndexRelay.Nostr.PubEvent
+
+  def index(%{events: events}) do
+    %{data: Enum.map(events, &data/1)}
+  end
+
+  defp data(%PubEvent{} = event) do
+    %{
+      id: event.id,
+      pubkey: event.pubkey,
+      created_at: event.created_at,
+      kind: event.kind,
+      content: event.content,
+      sig: event.sig,
+      tags: event.tags
+    }
+  end
+end
diff --git a/lib/gc_index_relay_web/router.ex b/lib/gc_index_relay_web/router.ex
index 2017efc..711d753 100644
--- a/lib/gc_index_relay_web/router.ex
+++ b/lib/gc_index_relay_web/router.ex
@@ -28,6 +28,7 @@ defmodule GcIndexRelayWeb.Router do
     get "/", ApiController, :index
     get "/events", FilterController, :index
     post "/events/filter", FilterController, :query
+    post "/publications/search", PublicationSearchController, :search
     resources "/events", EventController, only: [:show, :create, :delete]
   end
 
diff --git a/priv/static/swagger.json b/priv/static/swagger.json
index 1e0c16a..c1f9270 100644
--- a/priv/static/swagger.json
+++ b/priv/static/swagger.json
@@ -6,6 +6,14 @@
   },
   "host": "localhost:4000",
   "definitions": {
+    "PubEventList": {
+      "description": "A list of Nostr events",
+      "items": {
+        "$ref": "#/definitions/PubEvent"
+      },
+      "title": "PubEventList",
+      "type": "array"
+    },
     "PubEvent": {
       "description": "A signed Nostr event",
       "example": {
@@ -64,14 +72,6 @@
       ],
       "title": "PubEvent",
       "type": "object"
-    },
-    "PubEventList": {
-      "description": "A list of Nostr events",
-      "items": {
-        "$ref": "#/definitions/PubEvent"
-      },
-      "title": "PubEventList",
-      "type": "array"
     }
   },
   "schemes": [
@@ -225,13 +225,35 @@
           "Events"
         ]
       }
+    },
+    "/api/publications/search": {
+      "post": {
+        "description": "Exact-match search over publication index metadata tags: `d`, `title`, `author`, and `source`.\nMatching is case-insensitive and treats hyphens and spaces as equivalent. Partial substring\nmatches are not returned.\n",
+        "operationId": "search_publications",
+        "parameters": [],
+        "responses": {
+          "200": {
+            "description": "OK",
+            "schema": {
+              "$ref": "#/definitions/PubEventList"
+            }
+          },
+          "400": {
+            "description": "Bad Request"
+          }
+        },
+        "summary": "Search kind-30040 publication indexes by metadata",
+        "tags": [
+          "Publications"
+        ]
+      }
     }
   },
   "swagger": "2.0",
-  "produces": [
+  "consumes": [
     "application/json"
   ],
-  "consumes": [
+  "produces": [
     "application/json"
   ]
 }
\ No newline at end of file
diff --git a/test/gc_index_relay/nostr/publication_search_query_needles_test.exs b/test/gc_index_relay/nostr/publication_search_query_needles_test.exs
new file mode 100644
index 0000000..14018cb
--- /dev/null
+++ b/test/gc_index_relay/nostr/publication_search_query_needles_test.exs
@@ -0,0 +1,37 @@
+defmodule GcIndexRelay.Nostr.PublicationSearchQueryNeedlesTest do
+  use ExUnit.Case, async: true
+
+  alias GcIndexRelay.Nostr.PublicationSearch
+
+  @moduletag :unit
+
+  test "query_needles returns empty list for blank input" do
+    assert PublicationSearch.query_needles("") == []
+    assert PublicationSearch.query_needles("   ") == []
+  end
+
+  test "query_needles normalizes case, spaces, and hyphens" do
+    assert PublicationSearch.query_needles("Pride and Prejudice") == [
+             "pride and prejudice",
+             "pride-and-prejudice"
+           ]
+  end
+
+  test "query_needles strips surrounding quotes" do
+    assert PublicationSearch.query_needles(~s("Jane Eyre")) == ["jane eyre", "jane-eyre"]
+    assert PublicationSearch.query_needles("'Jane Eyre'") == ["jane eyre", "jane-eyre"]
+  end
+
+  test "query_needles collapses repeated whitespace and hyphens" do
+    assert PublicationSearch.query_needles("pride   and   prejudice") == [
+             "pride   and   prejudice",
+             "pride and prejudice",
+             "pride-and-prejudice"
+           ]
+
+    assert PublicationSearch.query_needles("pg1342--pride--and--prejudice") == [
+             "pg1342--pride--and--prejudice",
+             "pg1342-pride-and-prejudice"
+           ]
+  end
+end
diff --git a/test/gc_index_relay/nostr/publication_search_test.exs b/test/gc_index_relay/nostr/publication_search_test.exs
new file mode 100644
index 0000000..26cf17e
--- /dev/null
+++ b/test/gc_index_relay/nostr/publication_search_test.exs
@@ -0,0 +1,76 @@
+defmodule GcIndexRelay.Nostr.PublicationSearchTest do
+  use GcIndexRelay.DataCase
+
+  import GcIndexRelay.NostrFixtures
+
+  alias GcIndexRelay.Nostr
+  alias GcIndexRelay.Nostr.PublicationSearch
+
+  @moduletag :integration
+
+  defp insert_publication!(d, title, author, source, created_at \\ nil) do
+    attrs = %{
+      kind: 30_040,
+      content: "",
+      tags: [
+        ["d", d],
+        ["title", title],
+        ["author", author],
+        ["source", source]
+      ]
+    }
+
+    attrs = if created_at, do: Map.put(attrs, :created_at, created_at), else: attrs
+
+    event = valid_pub_event_fixture(attrs)
+    assert {:ok, _} = Nostr.create_event(event)
+    event
+  end
+
+  test "search finds exact title match" do
+    insert_publication!(
+      "pg1342-pride-and-prejudice",
+      "Pride and Prejudice",
+      "Jane Austen",
+      "https://www.gutenberg.org/ebooks/1342",
+      1_700_000_100
+    )
+
+    insert_publication!(
+      "other-book",
+      "Other Book",
+      "Someone",
+      "https://example.com/1",
+      1_700_000_200
+    )
+
+    assert {:ok, results} = PublicationSearch.search("pride and prejudice", limit: 10)
+    assert length(results) == 1
+    assert hd(results).kind == 30_040
+    assert Enum.any?(hd(results).tags, fn ["d", v] -> v == "pg1342-pride-and-prejudice" end)
+  end
+
+  test "search finds exact d-tag match" do
+    insert_publication!(
+      "pg1342-pride-and-prejudice",
+      "Pride and Prejudice",
+      "Jane Austen",
+      "https://www.gutenberg.org/ebooks/1342"
+    )
+
+    assert {:ok, results} = PublicationSearch.search("pg1342-pride-and-prejudice", limit: 10)
+    assert length(results) == 1
+  end
+
+  test "search rejects partial substring matches" do
+    insert_publication!(
+      "pg1342-pride-and-prejudice",
+      "Pride and Prejudice",
+      "Jane Austen",
+      "https://www.gutenberg.org/ebooks/1342"
+    )
+
+    assert {:ok, []} = PublicationSearch.search("pg1342", limit: 10)
+    assert {:ok, []} = PublicationSearch.search("pride-and", limit: 10)
+  end
+end
diff --git a/test/gc_index_relay_web/controllers/publication_search_controller_test.exs b/test/gc_index_relay_web/controllers/publication_search_controller_test.exs
new file mode 100644
index 0000000..49b3a38
--- /dev/null
+++ b/test/gc_index_relay_web/controllers/publication_search_controller_test.exs
@@ -0,0 +1,78 @@
+defmodule GcIndexRelayWeb.PublicationSearchControllerTest do
+  use GcIndexRelayWeb.ConnCase
+
+  import GcIndexRelay.NostrFixtures
+
+  alias GcIndexRelay.Nostr
+
+  @moduletag :integration
+
+  setup %{conn: conn} do
+    conn =
+      conn
+      |> put_req_header("accept", "application/json")
+      |> put_req_header("content-type", "application/json")
+
+    {:ok, conn: conn}
+  end
+
+  defp insert_publication!(d, title, author) do
+    event =
+      valid_pub_event_fixture(%{
+        kind: 30_040,
+        content: "",
+        tags: [
+          ["d", d],
+          ["title", title],
+          ["author", author]
+        ]
+      })
+
+    assert {:ok, _} = Nostr.create_event(event)
+    event
+  end
+
+  describe "POST /api/publications/search" do
+    test "returns matching kind-30040 events", %{conn: conn} do
+      pub_event =
+        insert_publication!("pg1342-pride-and-prejudice", "Pride and Prejudice", "Jane Austen")
+
+      conn =
+        post(conn, ~p"/api/publications/search", %{
+          "q" => "pride and prejudice",
+          "limit" => 10
+        })
+
+      assert %{"data" => [event]} = json_response(conn, 200)
+      assert event["id"] == pub_event.id
+      assert event["kind"] == 30_040
+    end
+
+    test "returns empty list when nothing matches", %{conn: conn} do
+      insert_publication!("pg1342-pride-and-prejudice", "Pride and Prejudice", "Jane Austen")
+
+      conn = post(conn, ~p"/api/publications/search", %{"q" => "pg1342", "limit" => 10})
+
+      assert %{"data" => []} = json_response(conn, 200)
+    end
+
+    test "returns 400 when q is missing", %{conn: conn} do
+      conn = post(conn, ~p"/api/publications/search", %{"limit" => 10})
+
+      assert %{"errors" => %{"detail" => "Missing required field: q"}} = json_response(conn, 400)
+    end
+
+    test "returns 400 when q is empty", %{conn: conn} do
+      conn = post(conn, ~p"/api/publications/search", %{"q" => "  ", "limit" => 10})
+
+      assert %{"errors" => %{"detail" => "Query q must not be empty."}} = json_response(conn, 400)
+    end
+
+    test "returns 400 when limit is out of range", %{conn: conn} do
+      conn = post(conn, ~p"/api/publications/search", %{"q" => "book", "limit" => 0})
+
+      assert %{"errors" => %{"detail" => "The limit must be between 1 and 100."}} =
+               json_response(conn, 400)
+    end
+  end
+end