diff --git a/.env.example b/.env.example
index d64d3c5..b20be0a 100644
--- a/.env.example
+++ b/.env.example
@@ -1,5 +1,5 @@
 # Copy this file to .env and fill in values, then run: source .env
-# The defaults below match the Docker container started by setup.sh.
+# The defaults below match setup.sh and compose.yaml: Postgres on host port 5455 (maps to 5432 in the container).
 
 export POSTGRES_HOST=localhost
 export POSTGRES_PORT=5455
@@ -7,3 +7,8 @@ export POSTGRES_USER=postgres
 export POSTGRES_PASSWORD=postgres
 export POSTGRES_DB=gc_index_relay_dev
 export REQUIRE_DB=true
+
+# Optional — only if you use docker compose for setup/migrator/mercury (override compose defaults):
+# export POSTGRES_RUNTIME_USER=gc_index_relay
+# export POSTGRES_RUNTIME_PASSWORD=gc_index_relay_runtime
+# export SECRET_KEY_BASE="$(mix phx.gen.secret)"
diff --git a/.formatter.exs b/.formatter.exs
index ef8840c..f9b487b 100644
--- a/.formatter.exs
+++ b/.formatter.exs
@@ -2,5 +2,5 @@
   import_deps: [:ecto, :ecto_sql, :phoenix],
   subdirectories: ["priv/*/migrations"],
   plugins: [Phoenix.LiveView.HTMLFormatter],
-  inputs: ["*.{heex,ex,exs}", "{config,lib,test}/**/*.{heex,ex,exs}", "priv/*/seeds.exs"]
+  inputs: ["*.{heex,ex,exs}", "{config,lib,test}/**/*.{heex,ex,exs}"]
 ]
diff --git a/README.md b/README.md
index dde6406..b053035 100644
--- a/README.md
+++ b/README.md
@@ -59,6 +59,18 @@ export REQUIRE_DB=true
 mix setup
 ```
 
+### Docker Compose (dev)
+
+Postgres is published on **localhost:5455**, same as the manual `docker run` and `setup.sh` flow. The stack works **without** a `.env` file (compose supplies defaults for DB names, the app DB role, and a dev-only `SECRET_KEY_BASE`). Override with `.env` if you want different passwords.
+
+```bash
+docker compose -f compose.yaml up -d
+```
+
+Use `POSTGRES_PORT=5455` and `POSTGRES_HOST=localhost` in `.env` when running `mix` on the host against this database (compose services talk to Postgres via the hostname `postgres` on the Docker network, not `localhost`).
+
+To reset the compose database volume: `docker compose -f compose.yaml down -v`.
+
 ### Starting the server
 
 ```bash
@@ -85,15 +97,13 @@ Unit tests (no database required):
 mix test.unit
 ```
 
-Integration tests (requires the database to be running). You must have `REQUIRE_DB=true` (included in `.env` from `setup.sh`) so the Repo starts under test:
+Integration tests (requires the database to be running). The `mix test.integration` task runs a subprocess with `REQUIRE_DB=true` so the Repo starts under test—you do not need to export it yourself. Still `source .env` (or set `POSTGRES_*`) so the test database host and port match your container:
 
 ```bash
 source .env
 mix test.integration
 ```
 
-Without `.env`: `REQUIRE_DB=true mix test.integration`
-
 Run the full integration probe against the relay API (covers all endpoints, CORS, NIP-11, NIP-70):
 
 ```bash
diff --git a/compose.yaml b/compose.yaml
index bc04026..464659b 100644
--- a/compose.yaml
+++ b/compose.yaml
@@ -3,15 +3,16 @@ services:
     image: docker.io/apache/age:release_PG17_1.6.0
     container_name: postgress_01
     restart: unless-stopped
-    user: 1000:1000 # Should match host user
+    # Host port matches setup.sh, .env.example, and config defaults (5455 → container 5432).
     ports:
-      - "5432:5432"
+      - "5455:5432"
+    # Named volume avoids host uid mismatches (do not combine image postgres user with user: 1000 + ./pgdata).
     volumes:
-      - ./pgdata:/var/lib/postgresql/data # Ensure host user owns the ./pgdata directory
+      - pgdata:/var/lib/postgresql/data
     environment:
-      POSTGRES_DB: ${POSTGRES_DB}
-      POSTGRES_USER: ${POSTGRES_USER}
-      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
+      POSTGRES_DB: ${POSTGRES_DB:-gc_index_relay_dev}
+      POSTGRES_USER: ${POSTGRES_USER:-postgres}
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-postgres}
     command: >
       postgres
     deploy:
@@ -22,18 +23,8 @@ services:
         reservations:
           cpus: "0.50"
           memory: 512M
-    security_opt:
-      - no-new-privileges:true
-    cap_drop:
-      - ALL
-    cap_add:
-      - CHOWN
-      - FOWNER
-      - SETUID
-      - SETGID
-    read_only: false
     healthcheck:
-      test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER}"]
+      test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER:-postgres} -d ${POSTGRES_DB:-gc_index_relay_dev}"]
       interval: 10s
       timeout: 5s
       retries: 5
@@ -48,12 +39,13 @@ services:
       postgres:
         condition: service_healthy
     environment:
-      POSTGRES_HOST: ${POSTGRES_HOST}
-      POSTGRES_USER: ${POSTGRES_USER}
-      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
-      POSTGRES_DB: ${POSTGRES_DB}
-      POSTGRES_RUNTIME_USER: ${POSTGRES_RUNTIME_USER}
-      POSTGRES_RUNTIME_PASSWORD: ${POSTGRES_RUNTIME_PASSWORD}
+      # Docker DNS name of this service (not localhost from .env — that is for host-side mix).
+      POSTGRES_HOST: postgres
+      POSTGRES_USER: ${POSTGRES_USER:-postgres}
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-postgres}
+      POSTGRES_DB: ${POSTGRES_DB:-gc_index_relay_dev}
+      POSTGRES_RUNTIME_USER: ${POSTGRES_RUNTIME_USER:-gc_index_relay}
+      POSTGRES_RUNTIME_PASSWORD: ${POSTGRES_RUNTIME_PASSWORD:-gc_index_relay_runtime}
 
   migrator:
     build:
@@ -67,8 +59,9 @@ services:
       setup:
         condition: service_completed_successfully
     environment:
-      DATABASE_URL: "ecto://${POSTGRES_USER}:${POSTGRES_PASSWORD}@${POSTGRES_HOST}/${POSTGRES_DB}"
-      SECRET_KEY_BASE: ${SECRET_KEY_BASE}
+      # Inside the compose network Postgres listens on 5432; 5455 is only the host publish port.
+      DATABASE_URL: "ecto://${POSTGRES_USER:-postgres}:${POSTGRES_PASSWORD:-postgres}@postgres:5432/${POSTGRES_DB:-gc_index_relay_dev}"
+      SECRET_KEY_BASE: ${SECRET_KEY_BASE:-0000000000000000000000000000000000000000000000000000000000000000}
 
   mercury:
     build:
@@ -84,8 +77,8 @@ services:
     ports:
       - "4000:4000"
     environment:
-      DATABASE_URL: "ecto://${POSTGRES_RUNTIME_USER}:${POSTGRES_RUNTIME_PASSWORD}@${POSTGRES_HOST}/${POSTGRES_DB}"
-      SECRET_KEY_BASE: ${SECRET_KEY_BASE}
+      DATABASE_URL: "ecto://${POSTGRES_RUNTIME_USER:-gc_index_relay}:${POSTGRES_RUNTIME_PASSWORD:-gc_index_relay_runtime}@postgres:5432/${POSTGRES_DB:-gc_index_relay_dev}"
+      SECRET_KEY_BASE: ${SECRET_KEY_BASE:-0000000000000000000000000000000000000000000000000000000000000000}
 
 volumes:
   pgdata:
diff --git a/config/config.exs b/config/config.exs
index d08e411..f9c395d 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -30,15 +30,6 @@ config :gc_index_relay, GcIndexRelayWeb.Endpoint,
   pubsub_server: GcIndexRelay.PubSub,
   live_view: [signing_salt: "CiEK2Shl"]
 
-# Configure the mailer
-#
-# By default it uses the "Local" adapter which stores the emails
-# locally. You can see the emails in your browser, at "/dev/mailbox".
-#
-# For production it's recommended to configure a different adapter
-# at the `config/runtime.exs`.
-config :gc_index_relay, GcIndexRelay.Mailer, adapter: Swoosh.Adapters.Local
-
 config :gc_index_relay, :phoenix_swagger,
   swagger_files: %{
     "priv/static/swagger.json" => [
diff --git a/config/dev.exs b/config/dev.exs
index cd093cf..2d660f8 100644
--- a/config/dev.exs
+++ b/config/dev.exs
@@ -60,7 +60,7 @@ config :gc_index_relay, GcIndexRelayWeb.Endpoint,
     ]
   ]
 
-# Enable dev routes for dashboard and mailbox
+# Enable dev routes for LiveDashboard
 config :gc_index_relay, dev_routes: true
 
 # Do not include metadata nor timestamps in development logs
@@ -80,6 +80,3 @@ config :phoenix_live_view,
   debug_attributes: true,
   # Enable helpful, but potentially expensive runtime checks
   enable_expensive_runtime_checks: true
-
-# Disable swoosh api client as it is only required for production adapters.
-config :swoosh, :api_client, false
diff --git a/config/prod.exs b/config/prod.exs
index bd1c8f1..8c110d1 100644
--- a/config/prod.exs
+++ b/config/prod.exs
@@ -15,12 +15,6 @@ config :gc_index_relay, GcIndexRelayWeb.Endpoint,
     hosts: ["localhost", "127.0.0.1"]
   ]
 
-# Configure Swoosh API Client
-config :swoosh, api_client: Swoosh.ApiClient.Req
-
-# Disable Swoosh Local Memory Storage
-config :swoosh, local: false
-
 # Do not print debug messages in production
 config :logger, level: :info
 
diff --git a/config/runtime.exs b/config/runtime.exs
index 2cf2104..4c14038 100644
--- a/config/runtime.exs
+++ b/config/runtime.exs
@@ -23,14 +23,17 @@ end
 config :gc_index_relay, GcIndexRelayWeb.Endpoint,
   http: [port: String.to_integer(System.get_env("PORT", "4000"))]
 
-# Defaults match setup.sh / .env.example (Apache AGE on host port 5455). Production
-# replaces this with DATABASE_URL in the block below.
-config :gc_index_relay, GcIndexRelay.Repo,
-  hostname: System.get_env("POSTGRES_HOST") || "localhost",
-  port: String.to_integer(System.get_env("POSTGRES_PORT") || "5455"),
-  username: System.get_env("POSTGRES_USER") || "postgres",
-  password: System.get_env("POSTGRES_PASSWORD") || "postgres",
-  database: System.get_env("POSTGRES_DB") || "gc_index_relay_dev"
+# Host-side dev/test: DB published on localhost:5455 (see setup.sh / .env.example).
+# Do not set this in :prod: DATABASE_URL omits port on purpose; merging these options
+# would keep port 5455 while the hostname came from the URL (e.g. postgres in Docker).
+if config_env() != :prod do
+  config :gc_index_relay, GcIndexRelay.Repo,
+    hostname: System.get_env("POSTGRES_HOST") || "localhost",
+    port: String.to_integer(System.get_env("POSTGRES_PORT") || "5455"),
+    username: System.get_env("POSTGRES_USER") || "postgres",
+    password: System.get_env("POSTGRES_PASSWORD") || "postgres",
+    database: System.get_env("POSTGRES_DB") || "gc_index_relay_dev"
+end
 
 if config_env() == :prod do
   database_url =
@@ -64,8 +67,6 @@ if config_env() == :prod do
 
   host = System.get_env("PHX_HOST") || "example.com"
 
-  config :gc_index_relay, :dns_cluster_query, System.get_env("DNS_CLUSTER_QUERY")
-
   config :gc_index_relay, GcIndexRelayWeb.Endpoint,
     url: [host: host, port: 443, scheme: "https"],
     http: [
@@ -139,22 +140,4 @@ if config_env() == :prod do
   #       force_ssl: [hsts: true]
   #
   # Check `Plug.SSL` for all available options in `force_ssl`.
-
-  # ## Configuring the mailer
-  #
-  # In production you need to configure the mailer to use a different adapter.
-  # Here is an example configuration for Mailgun:
-  #
-  #     config :gc_index_relay, GcIndexRelay.Mailer,
-  #       adapter: Swoosh.Adapters.Mailgun,
-  #       api_key: System.get_env("MAILGUN_API_KEY"),
-  #       domain: System.get_env("MAILGUN_DOMAIN")
-  #
-  # Most non-SMTP adapters require an API client. Swoosh supports Req, Hackney,
-  # and Finch out-of-the-box. This configuration is typically done at
-  # compile-time in your config/prod.exs:
-  #
-  #     config :swoosh, :api_client, Swoosh.ApiClient.Req
-  #
-  # See https://hexdocs.pm/swoosh/Swoosh.html#module-installation for details.
 end
diff --git a/config/test.exs b/config/test.exs
index 54bdbe8..6156591 100644
--- a/config/test.exs
+++ b/config/test.exs
@@ -2,6 +2,9 @@ import Config
 
 config :gc_index_relay, :start_repo, System.get_env("REQUIRE_DB") == "true"
 
+# Allow ConnCase HTTP tests to use the same SQL.Sandbox checkout as the test process (see Endpoint).
+config :gc_index_relay, sql_sandbox: true
+
 # Configure your database
 #
 # The MIX_TEST_PARTITION environment variable can be used
@@ -25,12 +28,6 @@ config :gc_index_relay, GcIndexRelayWeb.Endpoint,
   secret_key_base: "gSUz4Ek3rc6PKcY/imWwjsMbwk8g4+aS5HmD1/MyAmqlbSw+r0V83NjR7H0jnwI6",
   server: false
 
-# In test we don't send emails
-config :gc_index_relay, GcIndexRelay.Mailer, adapter: Swoosh.Adapters.Test
-
-# Disable swoosh api client as it is only required for production adapters
-config :swoosh, :api_client, false
-
 # Print only warnings and errors during test
 config :logger, level: :warning
 
diff --git a/lib/gc_index_relay/application.ex b/lib/gc_index_relay/application.ex
index d951900..9d5f5f2 100644
--- a/lib/gc_index_relay/application.ex
+++ b/lib/gc_index_relay/application.ex
@@ -11,7 +11,6 @@ defmodule GcIndexRelay.Application do
       [
         GcIndexRelayWeb.Telemetry,
         maybe_repo(),
-        {DNSCluster, query: Application.get_env(:gc_index_relay, :dns_cluster_query) || :ignore},
         {Phoenix.PubSub, name: GcIndexRelay.PubSub},
         # Start a worker by calling: GcIndexRelay.Worker.start_link(arg)
         # {GcIndexRelay.Worker, arg},
diff --git a/lib/gc_index_relay/mailer.ex b/lib/gc_index_relay/mailer.ex
deleted file mode 100644
index e68acca..0000000
--- a/lib/gc_index_relay/mailer.ex
+++ /dev/null
@@ -1,3 +0,0 @@
-defmodule GcIndexRelay.Mailer do
-  use Swoosh.Mailer, otp_app: :gc_index_relay
-end
diff --git a/lib/gc_index_relay/nostr.ex b/lib/gc_index_relay/nostr.ex
index 2685cb0..03c44cd 100644
--- a/lib/gc_index_relay/nostr.ex
+++ b/lib/gc_index_relay/nostr.ex
@@ -42,13 +42,21 @@ defmodule GcIndexRelay.Nostr do
     with {:ok, filter} <- Filter.from_map(filter_map),
          events <-
            from(e in Event)
-           |> Filter.apply(filter),
-         pub_events <-
-           Enum.map(events, fn event ->
-             {:ok, pub_event} = PubEvent.from_db(event)
-             pub_event
-           end) do
-      {:ok, pub_events}
+           |> Filter.apply(filter) do
+      pub_events_from_db(events)
+    end
+  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
 
@@ -58,8 +66,8 @@ defmodule GcIndexRelay.Nostr do
   def create_event(event) when is_struct(event, PubEvent) do
     with {:ok, event} <- Validator.validate_id(event),
          {:ok, event} <- Validator.validate_signature(event),
-         {:ok, event} <- Validator.validate_not_protected(event) do
-      db_event = PubEvent.to_db(event)
+         {:ok, event} <- Validator.validate_not_protected(event),
+         {:ok, db_event} <- PubEvent.to_db(event) do
       tags_as_maps = Enum.map(db_event.tags, &Map.from_struct/1)
       attrs = db_event |> Map.from_struct() |> Map.put(:tags, tags_as_maps)
 
diff --git a/lib/gc_index_relay/nostr/filter.ex b/lib/gc_index_relay/nostr/filter.ex
index 4815f7b..5053137 100644
--- a/lib/gc_index_relay/nostr/filter.ex
+++ b/lib/gc_index_relay/nostr/filter.ex
@@ -1,7 +1,10 @@
 defmodule GcIndexRelay.Nostr.Filter do
   @moduledoc """
-  An implementation of Nostr filters, including a struct representation and parsing and validation
-  functions.
+  Nostr NIP-01 filters: struct, parsing, validation, and query building.
+
+  Single-letter tag filter keys (`#p`, `#P`, `#e`, `#E`, …) are **case-sensitive**: uppercase and
+  lowercase names refer to different tags (e.g. NIP-22 uses `P`/`p`, `E`/`e`, `K`/`k` for distinct
+  semantics). Do not fold case when matching stored tag names.
   """
 
   alias GcIndexRelay.Nostr.Event
@@ -24,9 +27,11 @@ defmodule GcIndexRelay.Nostr.Filter do
 
   @spec from_map(map()) :: {:ok, t()} | {:error, String.t()}
   def from_map(map) when is_map(map) do
-    # Extract tag filters (keys starting with "#")
+    # Keys `#p` and `#P` (and likewise for every letter) are distinct filters; preserve case.
     tags =
       for {"#" <> k, v} <- map,
+          String.length(k) == 1,
+          String.match?(k, ~r/^[a-zA-Z]$/),
           do: {k, v},
           into: %{}
 
@@ -62,24 +67,36 @@ defmodule GcIndexRelay.Nostr.Filter do
 
   defp validate_not_empty(_map), do: :ok
 
-  # Validate that only known filter keys are present
+  # Validate that only known filter keys are present. `#` keys must be exactly `#` + one letter.
   @spec validate_known_keys(map()) :: :ok | {:error, String.t()}
   defp validate_known_keys(map) do
     known_keys = ["ids", "authors", "kinds", "since", "until", "limit"]
 
-    unknown_keys =
-      map
-      |> Map.keys()
-      |> Enum.reject(fn key ->
-        key in known_keys or String.starts_with?(key, "#")
-      end)
+    case Enum.find(Map.keys(map), &invalid_filter_map_key?(&1, known_keys)) do
+      nil -> :ok
+      <<"#", _::binary>> = key -> {:error, invalid_hash_filter_key_message(key)}
+      key -> {:error, "Unknown filter key: '#{key}'"}
+    end
+  end
 
-    case unknown_keys do
-      [] -> :ok
-      [key | _] -> {:error, "Unknown filter key: '#{key}'"}
+  defp invalid_filter_map_key?(key, known_keys) do
+    cond do
+      key in known_keys -> false
+      valid_tag_filter_key?(key) -> false
+      true -> true
     end
   end
 
+  defp valid_tag_filter_key?(<<"#", letter::binary-size(1)>>) do
+    String.match?(letter, ~r/^[a-zA-Z]$/)
+  end
+
+  defp valid_tag_filter_key?(_), do: false
+
+  defp invalid_hash_filter_key_message(key) do
+    "Invalid tag key '#{key}': must be a single letter (a-z, A-Z)"
+  end
+
   @spec validate_ids([String.t()] | nil) :: {:ok, [String.t()] | nil} | {:error, String.t()}
   defp validate_ids(nil), do: {:ok, nil}
   defp validate_ids([]), do: {:ok, nil}
diff --git a/lib/gc_index_relay/nostr/pub_event.ex b/lib/gc_index_relay/nostr/pub_event.ex
index 64038bf..4b12a9a 100644
--- a/lib/gc_index_relay/nostr/pub_event.ex
+++ b/lib/gc_index_relay/nostr/pub_event.ex
@@ -25,36 +25,42 @@ defmodule GcIndexRelay.Nostr.PubEvent do
   @doc """
   Converts a `GcIndexRelay.Nostr.PubEvent` to its corresponding `GcIndexRelay.Nostr.Event` and
   `GcIndexRelay.Nostr.Tag` representations.
-
-  Returns an Ecto for `GcIndexRelay.Nostr.Event`.
   """
-  @spec to_db(t()) :: Ecto.Schema.t()
-  def to_db(%__MODULE__{tags: tags} = pub_event) do
-    %Event{} = event = to_event(pub_event)
-    %{event | tags: to_tags(tags)}
+  @spec to_db(t()) :: {:ok, Event.t()} | {:error, atom()}
+  def to_db(%__MODULE__{} = pub_event) do
+    tags = pub_event.tags || []
+
+    with {:ok, event} <- to_event(pub_event) do
+      {:ok, %{event | tags: to_tags(tags)}}
+    end
   end
 
-  @spec to_event(t()) :: Ecto.Schema.t()
-  defp to_event(%__MODULE__{} = pub_event)
-       when is_binary(pub_event.id) and is_binary(pub_event.pubkey) and
-              is_integer(pub_event.created_at) and is_integer(pub_event.kind) and
-              is_binary(pub_event.sig) do
-    with {:ok, id} <- Base.decode16(pub_event.id, case: :lower),
+  @spec to_event(t()) :: {:ok, Event.t()} | {:error, atom()}
+  defp to_event(%__MODULE__{} = pub_event) do
+    with true <- pub_event_fields_valid?(pub_event),
+         {:ok, id} <- Base.decode16(pub_event.id, case: :lower),
          {:ok, pubkey} <- Base.decode16(pub_event.pubkey, case: :lower),
          {:ok, signature} <- Base.decode16(pub_event.sig, case: :lower) do
-      %Event{
-        id: id,
-        pubkey: pubkey,
-        created_at: DateTime.from_unix!(pub_event.created_at),
-        kind: pub_event.kind,
-        content: pub_event.content,
-        sig: signature
-      }
+      {:ok,
+       %Event{
+         id: id,
+         pubkey: pubkey,
+         created_at: DateTime.from_unix!(pub_event.created_at),
+         kind: pub_event.kind,
+         content: pub_event.content,
+         sig: signature
+       }}
     else
-      error -> {:error, error}
+      false -> {:error, :invalid_event}
+      :error -> {:error, :invalid_hex}
     end
   end
 
+  defp pub_event_fields_valid?(%__MODULE__{} = p) do
+    is_binary(p.id) and is_binary(p.pubkey) and is_integer(p.created_at) and is_integer(p.kind) and
+      is_binary(p.sig) and is_list(p.tags || [])
+  end
+
   @spec to_tags([[String.t()]]) :: [Ecto.Schema.t()]
   defp to_tags(tags) when is_list(tags) do
     for t <- tags do
diff --git a/lib/gc_index_relay_web.ex b/lib/gc_index_relay_web.ex
index 9fc27a3..8d742d9 100644
--- a/lib/gc_index_relay_web.ex
+++ b/lib/gc_index_relay_web.ex
@@ -17,7 +17,7 @@ defmodule GcIndexRelayWeb do
   those modules here.
   """
 
-  def static_paths, do: ~w(assets fonts images favicon.ico robots.txt)
+  def static_paths, do: ~w(assets images favicon.ico robots.txt)
 
   def router do
     quote do
diff --git a/lib/gc_index_relay_web/controllers/api_controller.ex b/lib/gc_index_relay_web/controllers/api_controller.ex
index 4782397..1532d61 100644
--- a/lib/gc_index_relay_web/controllers/api_controller.ex
+++ b/lib/gc_index_relay_web/controllers/api_controller.ex
@@ -2,9 +2,12 @@ defmodule GcIndexRelayWeb.ApiController do
   use GcIndexRelayWeb, :controller
 
   def index(conn, _params) do
+    relay_info = Application.fetch_env!(:gc_index_relay, :relay_info)
+
     json(conn, %{
-      relay: "Mercury Index-Relay",
-      version: Application.spec(:gc_index_relay, :vsn) |> to_string(),
+      relay: Keyword.fetch!(relay_info, :name),
+      version:
+        Keyword.get(relay_info, :version, Application.spec(:gc_index_relay, :vsn)) |> to_string(),
       endpoints: [
         %{
           method: "GET",
diff --git a/lib/gc_index_relay_web/controllers/event_controller.ex b/lib/gc_index_relay_web/controllers/event_controller.ex
index bd5670c..d8397fa 100644
--- a/lib/gc_index_relay_web/controllers/event_controller.ex
+++ b/lib/gc_index_relay_web/controllers/event_controller.ex
@@ -19,9 +19,20 @@ defmodule GcIndexRelayWeb.EventController do
     response(400, "BadRequest")
   end
 
+  @pub_event_keys ~w(id pubkey created_at kind tags content sig)
+
   def create(conn, %{"event" => event_params}) do
-    atoms_map = Map.new(event_params, fn {k, v} -> {String.to_existing_atom(k), v} end)
-    pub_event = struct(PubEvent, atoms_map)
+    pub_event =
+      @pub_event_keys
+      |> Enum.reduce(%{}, fn key, acc ->
+        case Map.get(event_params, key) do
+          nil -> acc
+          v -> Map.put(acc, String.to_existing_atom(key), v)
+        end
+      end)
+      |> Map.put_new(:tags, [])
+      |> Map.put_new(:content, "")
+      |> then(&struct(PubEvent, &1))
 
     with {:ok, _event} <- Nostr.create_event(pub_event) do
       conn
diff --git a/lib/gc_index_relay_web/controllers/fallback_controller.ex b/lib/gc_index_relay_web/controllers/fallback_controller.ex
index 0738f37..721b30a 100644
--- a/lib/gc_index_relay_web/controllers/fallback_controller.ex
+++ b/lib/gc_index_relay_web/controllers/fallback_controller.ex
@@ -28,6 +28,13 @@ defmodule GcIndexRelayWeb.FallbackController do
     |> json(%{errors: %{detail: message}})
   end
 
+  # Atom errors (e.g. from PubEvent.to_db/1).
+  def call(conn, {:error, reason}) when is_atom(reason) and reason != :not_found do
+    conn
+    |> put_status(:bad_request)
+    |> json(%{errors: %{detail: atom_error_message(reason)}})
+  end
+
   # This clause is an example of how to handle resources that cannot be found.
   def call(conn, {:error, :not_found}) do
     conn
@@ -42,4 +49,8 @@ defmodule GcIndexRelayWeb.FallbackController do
       _ -> false
     end)
   end
+
+  defp atom_error_message(:invalid_hex), do: "Invalid hexadecimal encoding in event fields"
+  defp atom_error_message(:invalid_event), do: "Invalid event structure"
+  defp atom_error_message(_), do: "Bad request"
 end
diff --git a/lib/gc_index_relay_web/controllers/filter_controller.ex b/lib/gc_index_relay_web/controllers/filter_controller.ex
index 979b757..df0510a 100644
--- a/lib/gc_index_relay_web/controllers/filter_controller.ex
+++ b/lib/gc_index_relay_web/controllers/filter_controller.ex
@@ -83,15 +83,26 @@ defmodule GcIndexRelayWeb.FilterController do
 
   @spec validate_param_values(map()) :: {:ok, map()} | {:error, String.t()}
   def validate_param_values(params) do
-    %{"limit" => limit} = params
+    with {:ok, limit} <- parse_limit_value(Map.get(params, "limit")) do
+      if limit < 1 or limit > 100 do
+        {:error, "The filter limit must be between 1 and 100."}
+      else
+        {:ok, Map.put(params, "limit", limit)}
+      end
+    end
+  end
 
-    if limit < 1 or limit > 100 do
-      {:error, "The filter limit must be between 1 and 100."}
-    else
-      {:ok, params}
+  defp parse_limit_value(v) when is_integer(v), do: {:ok, v}
+
+  defp parse_limit_value(v) when is_binary(v) do
+    case Integer.parse(v) do
+      {int, ""} -> {:ok, int}
+      _ -> {:error, "Invalid limit value: must be an integer"}
     end
   end
 
+  defp parse_limit_value(_), do: {:error, "Invalid limit value: must be an integer"}
+
   # Parse query parameters into a NIP-01 filter map
   @spec parse_query_params(map()) :: {:ok, map()} | {:error, String.t()}
   defp parse_query_params(params) do
@@ -151,14 +162,28 @@ defmodule GcIndexRelayWeb.FilterController do
     end)
   end
 
-  # Parse filter keys that represent tags. Note that only single-letter keys are treated as tags;
-  # all other keys are passed through unchanged.
+  # Bare `p=` / `P=` and `#p` / `#P` map to NIP-01 tag filters; letter case is significant (NIP-22).
   @spec parse_tag(String.t()) :: String.t()
   defp parse_tag(key) do
-    if byte_size(key) == 1 and
-         ((key >= "a" and key <= "z") or (key >= "A" and key <= "Z")),
-       do: "#" <> key,
-       else: key
+    cond do
+      single_bare_letter_tag_key?(key) ->
+        "#" <> key
+
+      single_letter_hash_tag_key?(key) ->
+        key
+
+      true ->
+        key
+    end
+  end
+
+  defp single_bare_letter_tag_key?(key) do
+    String.length(key) == 1 and String.match?(key, ~r/^[a-zA-Z]$/)
+  end
+
+  defp single_letter_hash_tag_key?(key) do
+    String.starts_with?(key, "#") and String.length(key) == 2 and
+      String.match?(String.at(key, 1), ~r/^[a-zA-Z]$/)
   end
 
   # Parse individual parameter based on its key
@@ -210,7 +235,7 @@ defmodule GcIndexRelayWeb.FilterController do
 
   # Handle single-letter tag filters without "#" prefix (e.g., "p" instead of "#p")
   # The "#" is trimmed by URL fragment parsing; bare single-letter keys are treated as tag filters
-  defp parse_param(<<letter>> = _key, value) when letter in ?a..?z do
+  defp parse_param(<<letter>> = _key, value) when letter in ?a..?z or letter in ?A..?Z do
     {:ok, String.split(value, ",")}
   end
 end
diff --git a/lib/gc_index_relay_web/endpoint.ex b/lib/gc_index_relay_web/endpoint.ex
index f123580..3704e4a 100644
--- a/lib/gc_index_relay_web/endpoint.ex
+++ b/lib/gc_index_relay_web/endpoint.ex
@@ -1,6 +1,12 @@
 defmodule GcIndexRelayWeb.Endpoint do
   use Phoenix.Endpoint, otp_app: :gc_index_relay
 
+  # Use runtime config so the plug is active whenever test.exs sets :sql_sandbox (compile_env
+  # would omit the plug if Endpoint was last compiled in an env without that key).
+  @sandbox_plug_opts Phoenix.Ecto.SQL.Sandbox.init([])
+
+  plug :maybe_sql_sandbox
+
   # The session will be stored in the cookie and signed,
   # this means its contents can be read but not tampered with.
   # Set :encryption_salt if you would also like to encrypt it.
@@ -54,4 +60,12 @@ defmodule GcIndexRelayWeb.Endpoint do
   plug GcIndexRelayWeb.Plugs.CORS
   plug GcIndexRelayWeb.Plugs.RelayInfo
   plug GcIndexRelayWeb.Router
+
+  def maybe_sql_sandbox(conn, _opts) do
+    if Application.get_env(:gc_index_relay, :sql_sandbox, false) do
+      Phoenix.Ecto.SQL.Sandbox.call(conn, @sandbox_plug_opts)
+    else
+      conn
+    end
+  end
 end
diff --git a/lib/gc_index_relay_web/plugs/cors.ex b/lib/gc_index_relay_web/plugs/cors.ex
index 9a3a110..88aac8d 100644
--- a/lib/gc_index_relay_web/plugs/cors.ex
+++ b/lib/gc_index_relay_web/plugs/cors.ex
@@ -42,23 +42,26 @@ defmodule GcIndexRelayWeb.Plugs.CORS do
   defp resolve_allow_origin(_conn, "*"), do: "*"
 
   defp resolve_allow_origin(conn, allow_origins) when is_list(allow_origins) do
-    cond do
-      "*" in allow_origins ->
-        "*"
-
-      Enum.any?(allow_origins, &(&1 == "*")) ->
-        "*"
-
-      true ->
-        case get_req_header(conn, "origin") do
-          [origin] -> if Enum.member?(allow_origins, origin), do: origin, else: nil
-          _ -> nil
-        end
+    if "*" in allow_origins do
+      "*"
+    else
+      origin_from_allowlist(conn, allow_origins)
     end
   end
 
   defp resolve_allow_origin(_conn, _), do: "*"
 
+  defp origin_from_allowlist(conn, allow_origins) do
+    case get_req_header(conn, "origin") do
+      [origin] -> origin_if_allowed(origin, allow_origins)
+      _ -> nil
+    end
+  end
+
+  defp origin_if_allowed(origin, allow_origins) do
+    if Enum.member?(allow_origins, origin), do: origin, else: nil
+  end
+
   defp restrictive_allowlist?("*"), do: false
 
   defp restrictive_allowlist?(list) when is_list(list) do
diff --git a/lib/gc_index_relay_web/plugs/relay_info.ex b/lib/gc_index_relay_web/plugs/relay_info.ex
index 74e2748..d13a79c 100644
--- a/lib/gc_index_relay_web/plugs/relay_info.ex
+++ b/lib/gc_index_relay_web/plugs/relay_info.ex
@@ -65,15 +65,22 @@ defmodule GcIndexRelayWeb.Plugs.RelayInfo do
         map
 
       url when is_binary(url) ->
-        if String.starts_with?(url, ["http://", "https://"]) do
-          map
-        else
-          path = if String.starts_with?(url, "/"), do: url, else: "/#{url}"
-          Map.put(map, key, "#{base_url}#{path}")
-        end
+        resolve_url_field(map, key, url, base_url)
 
       _ ->
         map
     end
   end
+
+  defp resolve_url_field(map, key, url, base_url) do
+    if String.starts_with?(url, ["http://", "https://"]) do
+      map
+    else
+      Map.put(map, key, "#{base_url}#{path_under_base(url)}")
+    end
+  end
+
+  defp path_under_base(url) do
+    if String.starts_with?(url, "/"), do: url, else: "/#{url}"
+  end
 end
diff --git a/lib/gc_index_relay_web/router.ex b/lib/gc_index_relay_web/router.ex
index b1049a3..2017efc 100644
--- a/lib/gc_index_relay_web/router.ex
+++ b/lib/gc_index_relay_web/router.ex
@@ -32,25 +32,36 @@ defmodule GcIndexRelayWeb.Router do
   end
 
   def swagger_info do
+    relay_info = Application.fetch_env!(:gc_index_relay, :relay_info)
+
+    title = Keyword.fetch!(relay_info, :name)
+    version = Keyword.fetch!(relay_info, :version) |> to_string()
+    base_desc = Keyword.fetch!(relay_info, :description)
+
+    description =
+      base_desc <>
+        supported_nips_swagger_suffix(Keyword.get(relay_info, :supported_nips, [])) <>
+        "\n\nRelay information document available at `GET /` with `Accept: application/nostr+json`."
+
     %{
+      # `wss` reserved for a future NIP-01 WebSocket endpoint; REST-only for now.
       schemes: ["https", "wss"],
       info: %{
-        version: Application.spec(:gc_index_relay, :vsn) |> to_string(),
-        title: "Mercury Index-Relay",
-        description: """
-        A Nostr index relay by [GitCitadel](https://gitcitadel.eu). \
-        Stores and serves Nostr events via a REST API with NIP-01 filter-based querying.
-
-        **Supported NIPs:** NIP-11 (relay info), NIP-70 (protected events)
-
-        Relay information document available at `GET /` with `Accept: application/nostr+json`.
-        """
+        version: version,
+        title: title,
+        description: description
       },
       consumes: ["application/json"],
       produces: ["application/json"]
     }
   end
 
+  defp supported_nips_swagger_suffix([]), do: ""
+
+  defp supported_nips_swagger_suffix(nips) do
+    "\n\n**Supported NIPs:** " <> Enum.map_join(nips, ", ", &"NIP-#{&1}")
+  end
+
   scope "/api/swagger" do
     forward "/", PhoenixSwagger.Plug.SwaggerUI,
       otp_app: :gc_index_relay,
@@ -62,7 +73,7 @@ defmodule GcIndexRelayWeb.Router do
   #   pipe_through :api
   # end
 
-  # Enable LiveDashboard and Swoosh mailbox preview in development
+  # Enable LiveDashboard in development
   if Application.compile_env(:gc_index_relay, :dev_routes) do
     # If you want to use the LiveDashboard in production, you should put
     # it behind authentication and allow only admins to access it.
@@ -75,7 +86,6 @@ defmodule GcIndexRelayWeb.Router do
       pipe_through :browser
 
       live_dashboard "/dashboard", metrics: GcIndexRelayWeb.Telemetry
-      forward "/mailbox", Plug.Swoosh.MailboxPreview
     end
   end
 end
diff --git a/lib/mix/tasks/test/integration.ex b/lib/mix/tasks/test/integration.ex
new file mode 100644
index 0000000..d8b774f
--- /dev/null
+++ b/lib/mix/tasks/test/integration.ex
@@ -0,0 +1,39 @@
+defmodule Mix.Tasks.Test.Integration do
+  use Mix.Task
+
+  @shortdoc "Runs integration tests with REQUIRE_DB=true (requires PostgreSQL)"
+
+  @moduledoc """
+  Creates the test database if needed, runs migrations, then runs tests tagged `:integration`.
+
+  Spawns a subprocess with `REQUIRE_DB=true` so the application starts `GcIndexRelay.Repo`
+  under `MIX_ENV=test`. Extra args are forwarded to `mix test` (e.g. `--failed`, `--trace` for line-by-line output).
+  """
+
+  @impl Mix.Task
+  def run(args) do
+    Mix.Task.run("loadconfig")
+
+    argv =
+      [
+        "REQUIRE_DB=true",
+        "MIX_ENV=test",
+        "mix",
+        "do",
+        "ecto.create",
+        "--quiet",
+        "+",
+        "ecto.migrate",
+        "--quiet",
+        "+",
+        "test",
+        "--only",
+        "integration"
+      ] ++ args
+
+    {_output, exit_code} =
+      System.cmd("env", argv, into: IO.stream(:stdio, :line), cd: File.cwd!())
+
+    System.halt(exit_code)
+  end
+end
diff --git a/mix.exs b/mix.exs
index 75ed626..62e3a68 100644
--- a/mix.exs
+++ b/mix.exs
@@ -30,7 +30,8 @@ defmodule GcIndexRelay.MixProject do
       preferred_envs: [
         precommit: :test,
         "test.unit": :test,
-        "test.integration": :test
+        "test.integration": :test,
+        "test.complete": :test
       ]
     ]
   end
@@ -53,13 +54,10 @@ defmodule GcIndexRelay.MixProject do
       {:phoenix_live_view, "~> 1.1.0"},
       {:lazy_html, ">= 0.1.0", only: :test},
       {:phoenix_live_dashboard, "~> 0.8.3"},
-      {:swoosh, "~> 1.16"},
-      {:req, "~> 0.5"},
       {:telemetry_metrics, "~> 1.0"},
       {:telemetry_poller, "~> 1.0"},
       {:gettext, "~> 1.0"},
       {:jason, "~> 1.2"},
-      {:dns_cluster, "~> 0.2.0"},
       {:bandit, "~> 1.5"},
       {:lib_secp256k1, "~> 0.7.1"},
       {:phoenix_swagger, "~> 0.8"},
@@ -76,21 +74,18 @@ defmodule GcIndexRelay.MixProject do
   defp aliases do
     [
       setup: ["deps.get", "ecto.setup"],
-      "ecto.setup": ["ecto.create", "ecto.migrate", "run priv/repo/seeds.exs"],
+      "ecto.setup": ["ecto.create", "ecto.migrate"],
       "ecto.reset": ["ecto.drop", "ecto.setup"],
       "test.unit": ["test --only unit"],
-      "test.integration": [
-        "ecto.create --quiet",
-        "ecto.migrate --quiet",
-        "test --only integration --trace"
-      ],
       precommit: [
         "compile --warnings-as-errors",
         "deps.unlock --unused",
         "format",
         "credo",
         "test.unit"
-      ]
+      ],
+      # Full local CI: precommit (compile, format, credo, unit) then integration tests (needs PostgreSQL).
+      "test.complete": ["precommit", "test.integration"]
     ]
   end
 end
diff --git a/mix.lock b/mix.lock
index e7fbfd1..b22cf02 100644
--- a/mix.lock
+++ b/mix.lock
@@ -5,24 +5,18 @@
   "credo": {:hex, :credo, "1.7.17", "f92b6aa5b26301eaa5a35e4d48ebf5aa1e7094ac00ae38f87086c562caf8a22f", [:mix], [{:bunt, "~> 0.2.1 or ~> 1.0", [hex: :bunt, repo: "hexpm", optional: false]}, {:file_system, "~> 0.2 or ~> 1.0", [hex: :file_system, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "1eb5645c835f0b6c9b5410f94b5a185057bcf6d62a9c2b476da971cde8749645"},
   "db_connection": {:hex, :db_connection, "2.9.0", "a6a97c5c958a2d7091a58a9be40caf41ab496b0701d21e1d1abff3fa27a7f371", [:mix], [{:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "17d502eacaf61829db98facf6f20808ed33da6ccf495354a41e64fe42f9c509c"},
   "decimal": {:hex, :decimal, "2.3.0", "3ad6255aa77b4a3c4f818171b12d237500e63525c2fd056699967a3e7ea20f62", [:mix], [], "hexpm", "a4d66355cb29cb47c3cf30e71329e58361cfcb37c34235ef3bf1d7bf3773aeac"},
-  "dns_cluster": {:hex, :dns_cluster, "0.2.0", "aa8eb46e3bd0326bd67b84790c561733b25c5ba2fe3c7e36f28e88f384ebcb33", [:mix], [], "hexpm", "ba6f1893411c69c01b9e8e8f772062535a4cf70f3f35bcc964a324078d8c8240"},
   "ecto": {:hex, :ecto, "3.13.5", "9d4a69700183f33bf97208294768e561f5c7f1ecf417e0fa1006e4a91713a834", [:mix], [{:decimal, "~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "df9efebf70cf94142739ba357499661ef5dbb559ef902b68ea1f3c1fabce36de"},
   "ecto_sql": {:hex, :ecto_sql, "3.13.4", "b6e9d07557ddba62508a9ce4a484989a5bb5e9a048ae0e695f6d93f095c25d60", [:mix], [{:db_connection, "~> 2.4.1 or ~> 2.5", [hex: :db_connection, repo: "hexpm", optional: false]}, {:ecto, "~> 3.13.0", [hex: :ecto, repo: "hexpm", optional: false]}, {:myxql, "~> 0.7", [hex: :myxql, repo: "hexpm", optional: true]}, {:postgrex, "~> 0.19 or ~> 1.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:tds, "~> 2.1.1 or ~> 2.2", [hex: :tds, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4.0 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "2b38cf0749ca4d1c5a8bcbff79bbe15446861ca12a61f9fba604486cb6b62a14"},
   "elixir_make": {:hex, :elixir_make, "0.9.0", "6484b3cd8c0cee58f09f05ecaf1a140a8c97670671a6a0e7ab4dc326c3109726", [:mix], [], "hexpm", "db23d4fd8b757462ad02f8aa73431a426fe6671c80b200d9710caf3d1dd0ffdb"},
   "expo": {:hex, :expo, "1.1.1", "4202e1d2ca6e2b3b63e02f69cfe0a404f77702b041d02b58597c00992b601db5", [:mix], [], "hexpm", "5fb308b9cb359ae200b7e23d37c76978673aa1b06e2b3075d814ce12c5811640"},
   "file_system": {:hex, :file_system, "1.1.1", "31864f4685b0148f25bd3fbef2b1228457c0c89024ad67f7a81a3ffbc0bbad3a", [:mix], [], "hexpm", "7a15ff97dfe526aeefb090a7a9d3d03aa907e100e262a0f8f7746b78f8f87a5d"},
-  "finch": {:hex, :finch, "0.20.0", "5330aefb6b010f424dcbbc4615d914e9e3deae40095e73ab0c1bb0968933cadf", [:mix], [{:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:mint, "~> 1.6.2 or ~> 1.7", [hex: :mint, repo: "hexpm", optional: false]}, {:nimble_options, "~> 0.4 or ~> 1.0", [hex: :nimble_options, repo: "hexpm", optional: false]}, {:nimble_pool, "~> 1.1", [hex: :nimble_pool, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "2658131a74d051aabfcba936093c903b8e89da9a1b63e430bee62045fa9b2ee2"},
   "fine": {:hex, :fine, "0.1.4", "b19a89c1476c7c57afb5f9314aed5960b5bc95d5277de4cb5ee8e1d1616ce379", [:mix], [], "hexpm", "be3324cc454a42d80951cf6023b9954e9ff27c6daa255483b3e8d608670303f5"},
   "gettext": {:hex, :gettext, "1.0.2", "5457e1fd3f4abe47b0e13ff85086aabae760497a3497909b8473e0acee57673b", [:mix], [{:expo, "~> 0.5.1 or ~> 1.0", [hex: :expo, repo: "hexpm", optional: false]}], "hexpm", "eab805501886802071ad290714515c8c4a17196ea76e5afc9d06ca85fb1bfeb3"},
   "hpax": {:hex, :hpax, "1.0.3", "ed67ef51ad4df91e75cc6a1494f851850c0bd98ebc0be6e81b026e765ee535aa", [:mix], [], "hexpm", "8eab6e1cfa8d5918c2ce4ba43588e894af35dbd8e91e6e55c817bca5847df34a"},
-  "idna": {:hex, :idna, "6.1.1", "8a63070e9f7d0c62eb9d9fcb360a7de382448200fbbd1b106cc96d3d8099df8d", [:rebar3], [{:unicode_util_compat, "~> 0.7.0", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm", "92376eb7894412ed19ac475e4a86f7b413c1b9fbb5bd16dccd57934157944cea"},
   "jason": {:hex, :jason, "1.4.4", "b9226785a9aa77b6857ca22832cffa5d5011a667207eb2a0ad56adb5db443b8a", [:mix], [{:decimal, "~> 1.0 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "c5eb0cab91f094599f94d55bc63409236a8ec69a21a67814529e8d5f6cc90b3b"},
   "lazy_html": {:hex, :lazy_html, "0.1.8", "677a8642e644eef8de98f3040e2520d42d0f0f8bd6c5cd49db36504e34dffe91", [:make, :mix], [{:cc_precompiler, "~> 0.1", [hex: :cc_precompiler, repo: "hexpm", optional: false]}, {:elixir_make, "~> 0.9.0", [hex: :elixir_make, repo: "hexpm", optional: false]}, {:fine, "~> 0.1.0", [hex: :fine, repo: "hexpm", optional: false]}], "hexpm", "0d8167d930b704feb94b41414ca7f5779dff9bca7fcf619fcef18de138f08736"},
   "lib_secp256k1": {:hex, :lib_secp256k1, "0.7.1", "53cad778b8da3a29e453a7a477517d99fb5f13f615c8050eb2db8fd1dce7a1db", [:make, :mix], [{:elixir_make, "~> 0.9", [hex: :elixir_make, repo: "hexpm", optional: false]}], "hexpm", "78bdd3661a17448aff5aeec5ca74c8ddbc09b01f0ecfa3ba1aba3e8ae47ab2b3"},
   "mime": {:hex, :mime, "2.0.7", "b8d739037be7cd402aee1ba0306edfdef982687ee7e9859bee6198c1e7e2f128", [:mix], [], "hexpm", "6171188e399ee16023ffc5b76ce445eb6d9672e2e241d2df6050f3c771e80ccd"},
-  "mint": {:hex, :mint, "1.7.1", "113fdb2b2f3b59e47c7955971854641c61f378549d73e829e1768de90fc1abf1", [:mix], [{:castore, "~> 0.1.0 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: true]}, {:hpax, "~> 0.1.1 or ~> 0.2.0 or ~> 1.0", [hex: :hpax, repo: "hexpm", optional: false]}], "hexpm", "fceba0a4d0f24301ddee3024ae116df1c3f4bb7a563a731f45fdfeb9d39a231b"},
-  "nimble_options": {:hex, :nimble_options, "1.1.1", "e3a492d54d85fc3fd7c5baf411d9d2852922f66e69476317787a7b2bb000a61b", [:mix], [], "hexpm", "821b2470ca9442c4b6984882fe9bb0389371b8ddec4d45a9504f00a66f650b44"},
-  "nimble_pool": {:hex, :nimble_pool, "1.1.0", "bf9c29fbdcba3564a8b800d1eeb5a3c58f36e1e11d7b7fb2e084a643f645f06b", [:mix], [], "hexpm", "af2e4e6b34197db81f7aad230c1118eac993acc0dae6bc83bac0126d4ae0813a"},
   "phoenix": {:hex, :phoenix, "1.8.3", "49ac5e485083cb1495a905e47eb554277bdd9c65ccb4fc5100306b350151aa95", [:mix], [{:bandit, "~> 1.0", [hex: :bandit, repo: "hexpm", optional: true]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:phoenix_pubsub, "~> 2.1", [hex: :phoenix_pubsub, repo: "hexpm", optional: false]}, {:phoenix_template, "~> 1.0", [hex: :phoenix_template, repo: "hexpm", optional: false]}, {:phoenix_view, "~> 2.0", [hex: :phoenix_view, repo: "hexpm", optional: true]}, {:plug, "~> 1.14", [hex: :plug, repo: "hexpm", optional: false]}, {:plug_cowboy, "~> 2.7", [hex: :plug_cowboy, repo: "hexpm", optional: true]}, {:plug_crypto, "~> 1.2 or ~> 2.0", [hex: :plug_crypto, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}, {:websock_adapter, "~> 0.5.3", [hex: :websock_adapter, repo: "hexpm", optional: false]}], "hexpm", "36169f95cc2e155b78be93d9590acc3f462f1e5438db06e6248613f27c80caec"},
   "phoenix_ecto": {:hex, :phoenix_ecto, "4.7.0", "75c4b9dfb3efdc42aec2bd5f8bccd978aca0651dbcbc7a3f362ea5d9d43153c6", [:mix], [{:ecto, "~> 3.5", [hex: :ecto, repo: "hexpm", optional: false]}, {:phoenix_html, "~> 2.14.2 or ~> 3.0 or ~> 4.1", [hex: :phoenix_html, repo: "hexpm", optional: true]}, {:plug, "~> 1.9", [hex: :plug, repo: "hexpm", optional: false]}, {:postgrex, "~> 0.16 or ~> 1.0", [hex: :postgrex, repo: "hexpm", optional: true]}], "hexpm", "1d75011e4254cb4ddf823e81823a9629559a1be93b4321a6a5f11a5306fbf4cc"},
   "phoenix_html": {:hex, :phoenix_html, "4.3.0", "d3577a5df4b6954cd7890c84d955c470b5310bb49647f0a114a6eeecc850f7ad", [:mix], [], "hexpm", "3eaa290a78bab0f075f791a46a981bbe769d94bc776869f4f3063a14f30497ad"},
@@ -35,13 +29,10 @@
   "plug": {:hex, :plug, "1.19.1", "09bac17ae7a001a68ae393658aa23c7e38782be5c5c00c80be82901262c394c0", [:mix], [{:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:plug_crypto, "~> 1.1.1 or ~> 1.2 or ~> 2.0", [hex: :plug_crypto, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4.3 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "560a0017a8f6d5d30146916862aaf9300b7280063651dd7e532b8be168511e62"},
   "plug_crypto": {:hex, :plug_crypto, "2.1.1", "19bda8184399cb24afa10be734f84a16ea0a2bc65054e23a62bb10f06bc89491", [:mix], [], "hexpm", "6470bce6ffe41c8bd497612ffde1a7e4af67f36a15eea5f921af71cf3e11247c"},
   "postgrex": {:hex, :postgrex, "0.22.0", "fb027b58b6eab1f6de5396a2abcdaaeb168f9ed4eccbb594e6ac393b02078cbd", [:mix], [{:db_connection, "~> 2.9", [hex: :db_connection, repo: "hexpm", optional: false]}, {:decimal, "~> 1.5 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:table, "~> 0.1.0", [hex: :table, repo: "hexpm", optional: true]}], "hexpm", "a68c4261e299597909e03e6f8ff5a13876f5caadaddd0d23af0d0a61afcc5d84"},
-  "req": {:hex, :req, "0.5.17", "0096ddd5b0ed6f576a03dde4b158a0c727215b15d2795e59e0916c6971066ede", [:mix], [{:brotli, "~> 0.3.1", [hex: :brotli, repo: "hexpm", optional: true]}, {:ezstd, "~> 1.0", [hex: :ezstd, repo: "hexpm", optional: true]}, {:finch, "~> 0.17", [hex: :finch, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}, {:mime, "~> 2.0.6 or ~> 2.1", [hex: :mime, repo: "hexpm", optional: false]}, {:nimble_csv, "~> 1.0", [hex: :nimble_csv, repo: "hexpm", optional: true]}, {:plug, "~> 1.0", [hex: :plug, repo: "hexpm", optional: true]}], "hexpm", "0b8bc6ffdfebbc07968e59d3ff96d52f2202d0536f10fef4dc11dc02a2a43e39"},
-  "swoosh": {:hex, :swoosh, "1.20.0", "b04134c2b302da74c3a95ca4ddde191e4854d2847d6687783fecb023a9647598", [:mix], [{:bandit, ">= 1.0.0", [hex: :bandit, repo: "hexpm", optional: true]}, {:cowboy, "~> 1.1 or ~> 2.4", [hex: :cowboy, repo: "hexpm", optional: true]}, {:ex_aws, "~> 2.1", [hex: :ex_aws, repo: "hexpm", optional: true]}, {:finch, "~> 0.6", [hex: :finch, repo: "hexpm", optional: true]}, {:gen_smtp, "~> 0.13 or ~> 1.0", [hex: :gen_smtp, repo: "hexpm", optional: true]}, {:hackney, "~> 1.9", [hex: :hackney, repo: "hexpm", optional: true]}, {:idna, "~> 6.0", [hex: :idna, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}, {:mail, "~> 0.2", [hex: :mail, repo: "hexpm", optional: true]}, {:mime, "~> 1.1 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:mua, "~> 0.2.3", [hex: :mua, repo: "hexpm", optional: true]}, {:multipart, "~> 0.4", [hex: :multipart, repo: "hexpm", optional: true]}, {:plug, "~> 1.9", [hex: :plug, repo: "hexpm", optional: true]}, {:plug_cowboy, ">= 1.0.0", [hex: :plug_cowboy, repo: "hexpm", optional: true]}, {:req, "~> 0.5.10 or ~> 0.6 or ~> 1.0", [hex: :req, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4.2 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "13e610f709bae54851d68afb6862882aa646e5c974bf49e3bf5edd84a73cf213"},
   "telemetry": {:hex, :telemetry, "1.3.0", "fedebbae410d715cf8e7062c96a1ef32ec22e764197f70cda73d82778d61e7a2", [:rebar3], [], "hexpm", "7015fc8919dbe63764f4b4b87a95b7c0996bd539e0d499be6ec9d7f3875b79e6"},
   "telemetry_metrics": {:hex, :telemetry_metrics, "1.1.0", "5bd5f3b5637e0abea0426b947e3ce5dd304f8b3bc6617039e2b5a008adc02f8f", [:mix], [{:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "e7b79e8ddfde70adb6db8a6623d1778ec66401f366e9a8f5dd0955c56bc8ce67"},
   "telemetry_poller": {:hex, :telemetry_poller, "1.3.0", "d5c46420126b5ac2d72bc6580fb4f537d35e851cc0f8dbd571acf6d6e10f5ec7", [:rebar3], [{:telemetry, "~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "51f18bed7128544a50f75897db9974436ea9bfba560420b646af27a9a9b35211"},
   "thousand_island": {:hex, :thousand_island, "1.4.3", "2158209580f633be38d43ec4e3ce0a01079592b9657afff9080d5d8ca149a3af", [:mix], [{:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "6e4ce09b0fd761a58594d02814d40f77daff460c48a7354a15ab353bb998ea0b"},
-  "unicode_util_compat": {:hex, :unicode_util_compat, "0.7.1", "a48703a25c170eedadca83b11e88985af08d35f37c6f664d6dcfb106a97782fc", [:rebar3], [], "hexpm", "b3a917854ce3ae233619744ad1e0102e05673136776fb2fa76234f3e03b23642"},
   "websock": {:hex, :websock, "0.5.3", "2f69a6ebe810328555b6fe5c831a851f485e303a7c8ce6c5f675abeb20ebdadc", [:mix], [], "hexpm", "6105453d7fac22c712ad66fab1d45abdf049868f253cf719b625151460b8b453"},
   "websock_adapter": {:hex, :websock_adapter, "0.5.9", "43dc3ba6d89ef5dec5b1d0a39698436a1e856d000d84bf31a3149862b01a287f", [:mix], [{:bandit, ">= 0.6.0", [hex: :bandit, repo: "hexpm", optional: true]}, {:plug, "~> 1.14", [hex: :plug, repo: "hexpm", optional: false]}, {:plug_cowboy, "~> 2.6", [hex: :plug_cowboy, repo: "hexpm", optional: true]}, {:websock, "~> 0.5", [hex: :websock, repo: "hexpm", optional: false]}], "hexpm", "5534d5c9adad3c18a0f58a9371220d75a803bf0b9a3d87e6fe072faaeed76a08"},
 }
diff --git a/priv/repo/seeds.exs b/priv/repo/seeds.exs
deleted file mode 100644
index fa270c1..0000000
--- a/priv/repo/seeds.exs
+++ /dev/null
@@ -1,11 +0,0 @@
-# Script for populating the database. You can run it as:
-#
-#     mix run priv/repo/seeds.exs
-#
-# Inside the script, you can read and write to any of your
-# repositories directly:
-#
-#     GcIndexRelay.Repo.insert!(%GcIndexRelay.SomeSchema{})
-#
-# We recommend using the bang functions (`insert!`, `update!`
-# and so on) as they will fail if something goes wrong.
diff --git a/priv/static/swagger.json b/priv/static/swagger.json
index 1117b3c..1e0c16a 100644
--- a/priv/static/swagger.json
+++ b/priv/static/swagger.json
@@ -1,19 +1,11 @@
 {
   "info": {
     "version": "0.2.0",
-    "description": "A Nostr index relay by [GitCitadel](https://gitcitadel.eu). Stores and serves Nostr events via a REST API with NIP-01 filter-based querying.\n\n**Supported NIPs:** NIP-11 (relay info), NIP-70 (protected events)\n\nRelay information document available at `GET /` with `Accept: application/nostr+json`.\n",
+    "description": "A Nostr index relay for the http protocol, from GitCitadel. Featuring a RESTful API and Swagger, it specializes in swift retrieval or publications, repos, and similar graphs of related events\n\n**Supported NIPs:** NIP-11, NIP-70\n\nRelay information document available at `GET /` with `Accept: application/nostr+json`.",
     "title": "Mercury Index-Relay"
   },
   "host": "localhost:4000",
   "definitions": {
-    "PubEventList": {
-      "description": "A list of Nostr events",
-      "items": {
-        "$ref": "#/definitions/PubEvent"
-      },
-      "title": "PubEventList",
-      "type": "array"
-    },
     "PubEvent": {
       "description": "A signed Nostr event",
       "example": {
@@ -72,6 +64,14 @@
       ],
       "title": "PubEvent",
       "type": "object"
+    },
+    "PubEventList": {
+      "description": "A list of Nostr events",
+      "items": {
+        "$ref": "#/definitions/PubEvent"
+      },
+      "title": "PubEventList",
+      "type": "array"
     }
   },
   "schemes": [
@@ -228,10 +228,10 @@
     }
   },
   "swagger": "2.0",
-  "consumes": [
+  "produces": [
     "application/json"
   ],
-  "produces": [
+  "consumes": [
     "application/json"
   ]
 }
\ No newline at end of file
diff --git a/test/gc_index_relay/nostr/filter_test.exs b/test/gc_index_relay/nostr/filter_test.exs
index d1478ef..40147cf 100644
--- a/test/gc_index_relay/nostr/filter_test.exs
+++ b/test/gc_index_relay/nostr/filter_test.exs
@@ -27,11 +27,22 @@ defmodule GcIndexRelay.Nostr.FilterTest do
       assert filter.tags == %{"e" => ["value1", "value2"]}
     end
 
-    test "returns {:ok, filter} with valid tags (uppercase)" do
+    test "returns {:ok, filter} with valid tags (uppercase letter is distinct from lowercase)" do
       assert {:ok, filter} = Filter.from_map(%{"#E" => ["value1"]})
       assert filter.tags == %{"E" => ["value1"]}
     end
 
+    test "returns {:ok, filter} with both #e and #E as separate tag filters" do
+      assert {:ok, filter} =
+               Filter.from_map(%{
+                 "#e" => ["lowercase-scope"],
+                 "#E" => ["uppercase-scope"],
+                 "limit" => 10
+               })
+
+      assert filter.tags == %{"e" => ["lowercase-scope"], "E" => ["uppercase-scope"]}
+    end
+
     test "returns {:ok, filter} with multiple valid tags" do
       assert {:ok, filter} = Filter.from_map(%{"#e" => ["val1"], "#p" => ["val2"]})
       assert filter.tags == %{"e" => ["val1"], "p" => ["val2"]}
diff --git a/test/gc_index_relay/nostr/pub_event_test.exs b/test/gc_index_relay/nostr/pub_event_test.exs
index 7ab9f7e..893b894 100644
--- a/test/gc_index_relay/nostr/pub_event_test.exs
+++ b/test/gc_index_relay/nostr/pub_event_test.exs
@@ -12,7 +12,7 @@ defmodule GcIndexRelay.Nostr.PubEventTest do
   describe "to_db/1" do
     test "converts tags with name and value" do
       pub_event = valid_pub_event_fixture(tags: [["e", "abc123"], ["p", "def456"]])
-      event = PubEvent.to_db(pub_event)
+      assert {:ok, event} = PubEvent.to_db(pub_event)
 
       assert [tag1, tag2] = event.tags
       assert %Tag{name: "e", value: "abc123", additional_values: []} = tag1
@@ -22,16 +22,33 @@ defmodule GcIndexRelay.Nostr.PubEventTest do
     test "converts tags with additional values" do
       tags = [["p", "pubkey_hex", "wss://relay.example.com", "alice"]]
       pub_event = valid_pub_event_fixture(tags: tags)
-      event = PubEvent.to_db(pub_event)
+      assert {:ok, event} = PubEvent.to_db(pub_event)
 
       assert [tag] = event.tags
       assert %Tag{name: "p", value: "pubkey_hex"} = tag
       assert tag.additional_values == ["wss://relay.example.com", "alice"]
     end
 
+    test "maps reference kind 1111 tags including uppercase names and extras" do
+      pub_event = reference_kind1111_pub_event()
+      assert {:ok, event} = PubEvent.to_db(pub_event)
+
+      assert length(event.tags) == 7
+
+      e_upper = Enum.find(event.tags, &(&1.name == "E"))
+      assert e_upper.value == "6e35ec65661c5e2c453f9585a785b3f082c1daf9f769b3bb208af5459d178fca"
+
+      assert e_upper.additional_values == [
+               "wss://nostr.land/",
+               "dd664d5e4016433a8cd69f005ae1480804351789b59de5af06276de65633d319"
+             ]
+
+      assert %Tag{name: "client", value: "imwald", additional_values: []} in event.tags
+    end
+
     test "preserves empty content" do
       pub_event = valid_pub_event_fixture(content: "")
-      event = PubEvent.to_db(pub_event)
+      assert {:ok, event} = PubEvent.to_db(pub_event)
 
       assert event.content == ""
     end
@@ -96,7 +113,8 @@ defmodule GcIndexRelay.Nostr.PubEventTest do
     test "preserves all fields for a basic event" do
       pub_event = valid_pub_event_fixture(content: "round-trip test")
 
-      assert {:ok, result} = pub_event |> PubEvent.to_db() |> PubEvent.from_db()
+      assert {:ok, db} = PubEvent.to_db(pub_event)
+      assert {:ok, result} = PubEvent.from_db(db)
 
       assert result.id == pub_event.id
       assert result.pubkey == pub_event.pubkey
@@ -110,7 +128,8 @@ defmodule GcIndexRelay.Nostr.PubEventTest do
     test "preserves event with empty tags" do
       pub_event = valid_pub_event_fixture(tags: [])
 
-      assert {:ok, result} = pub_event |> PubEvent.to_db() |> PubEvent.from_db()
+      assert {:ok, db} = PubEvent.to_db(pub_event)
+      assert {:ok, result} = PubEvent.from_db(db)
       assert result.tags == []
     end
 
@@ -123,7 +142,8 @@ defmodule GcIndexRelay.Nostr.PubEventTest do
 
       pub_event = valid_pub_event_fixture(tags: tags)
 
-      assert {:ok, result} = pub_event |> PubEvent.to_db() |> PubEvent.from_db()
+      assert {:ok, db} = PubEvent.to_db(pub_event)
+      assert {:ok, result} = PubEvent.from_db(db)
       assert result.tags == tags
     end
 
@@ -132,7 +152,8 @@ defmodule GcIndexRelay.Nostr.PubEventTest do
 
       pub_event = valid_pub_event_fixture(tags: tags)
 
-      assert {:ok, result} = pub_event |> PubEvent.to_db() |> PubEvent.from_db()
+      assert {:ok, db} = PubEvent.to_db(pub_event)
+      assert {:ok, result} = PubEvent.from_db(db)
       assert result.tags == tags
     end
 
@@ -145,14 +166,16 @@ defmodule GcIndexRelay.Nostr.PubEventTest do
 
       pub_event = valid_pub_event_fixture(tags: tags)
 
-      assert {:ok, result} = pub_event |> PubEvent.to_db() |> PubEvent.from_db()
+      assert {:ok, db} = PubEvent.to_db(pub_event)
+      assert {:ok, result} = PubEvent.from_db(db)
       assert result.tags == tags
     end
 
     test "preserves event with empty content" do
       pub_event = valid_pub_event_fixture(content: "")
 
-      assert {:ok, result} = pub_event |> PubEvent.to_db() |> PubEvent.from_db()
+      assert {:ok, db} = PubEvent.to_db(pub_event)
+      assert {:ok, result} = PubEvent.from_db(db)
       assert result.content == ""
     end
 
@@ -160,8 +183,10 @@ defmodule GcIndexRelay.Nostr.PubEventTest do
       pub_event_1 = valid_pub_event_fixture(keypair: :keypair1)
       pub_event_2 = valid_pub_event_fixture(keypair: :keypair2)
 
-      assert {:ok, result_1} = pub_event_1 |> PubEvent.to_db() |> PubEvent.from_db()
-      assert {:ok, result_2} = pub_event_2 |> PubEvent.to_db() |> PubEvent.from_db()
+      assert {:ok, db1} = PubEvent.to_db(pub_event_1)
+      assert {:ok, db2} = PubEvent.to_db(pub_event_2)
+      assert {:ok, result_1} = PubEvent.from_db(db1)
+      assert {:ok, result_2} = PubEvent.from_db(db2)
 
       assert result_1.pubkey == pub_event_1.pubkey
       assert result_2.pubkey == pub_event_2.pubkey
@@ -170,31 +195,25 @@ defmodule GcIndexRelay.Nostr.PubEventTest do
   end
 
   describe "to_db/1 with invalid hex input" do
-    test "raises on invalid hex in id" do
+    test "returns error on invalid hex in id" do
       pub_event = valid_pub_event_fixture()
       invalid = %{pub_event | id: String.duplicate("zz", 32)}
 
-      assert_raise MatchError, fn ->
-        PubEvent.to_db(invalid)
-      end
+      assert {:error, :invalid_hex} = PubEvent.to_db(invalid)
     end
 
-    test "raises on invalid hex in pubkey" do
+    test "returns error on invalid hex in pubkey" do
       pub_event = valid_pub_event_fixture()
       invalid = %{pub_event | pubkey: String.duplicate("zz", 32)}
 
-      assert_raise MatchError, fn ->
-        PubEvent.to_db(invalid)
-      end
+      assert {:error, :invalid_hex} = PubEvent.to_db(invalid)
     end
 
-    test "raises on invalid hex in sig" do
+    test "returns error on invalid hex in sig" do
       pub_event = valid_pub_event_fixture()
       invalid = %{pub_event | sig: String.duplicate("zz", 64)}
 
-      assert_raise MatchError, fn ->
-        PubEvent.to_db(invalid)
-      end
+      assert {:error, :invalid_hex} = PubEvent.to_db(invalid)
     end
   end
 end
diff --git a/test/gc_index_relay/nostr/validator_test.exs b/test/gc_index_relay/nostr/validator_test.exs
index a05bb70..2636730 100644
--- a/test/gc_index_relay/nostr/validator_test.exs
+++ b/test/gc_index_relay/nostr/validator_test.exs
@@ -175,5 +175,12 @@ defmodule GcIndexRelay.Nostr.ValidatorTest do
       assert {:ok, ^event} = Validator.validate_id(event)
       assert {:ok, ^event} = Validator.validate_signature(event)
     end
+
+    test "validates real kind 1111 multi-tag reference event" do
+      event = reference_kind1111_pub_event()
+
+      assert {:ok, ^event} = Validator.validate_id(event)
+      assert {:ok, ^event} = Validator.validate_signature(event)
+    end
   end
 end
diff --git a/test/gc_index_relay/nostr_test.exs b/test/gc_index_relay/nostr_test.exs
index 665bfb1..27b0e2e 100644
--- a/test/gc_index_relay/nostr_test.exs
+++ b/test/gc_index_relay/nostr_test.exs
@@ -1,5 +1,22 @@
 defmodule GcIndexRelay.NostrTest do
   use GcIndexRelay.DataCase
 
+  import GcIndexRelay.NostrFixtures
+
   @moduletag :integration
+
+  describe "reference kind 1111 event" do
+    test "create_event and get_event round-trip all fields and tags" do
+      event = reference_kind1111_pub_event()
+
+      assert {:ok, _} = GcIndexRelay.Nostr.create_event(event)
+      assert {:ok, loaded} = GcIndexRelay.Nostr.get_event(event.id)
+
+      assert loaded.kind == event.kind
+      assert loaded.content == event.content
+      assert loaded.pubkey == event.pubkey
+      assert loaded.created_at == event.created_at
+      assert loaded.tags == event.tags
+    end
+  end
 end
diff --git a/test/gc_index_relay_web/controllers/error_html_test.exs b/test/gc_index_relay_web/controllers/error_html_test.exs
index c9f9cb1..fb78cb7 100644
--- a/test/gc_index_relay_web/controllers/error_html_test.exs
+++ b/test/gc_index_relay_web/controllers/error_html_test.exs
@@ -1,6 +1,8 @@
 defmodule GcIndexRelayWeb.ErrorHTMLTest do
   use GcIndexRelayWeb.ConnCase, async: true
 
+  @moduletag :unit
+
   # Bring render_to_string/4 for testing custom views
   import Phoenix.Template, only: [render_to_string: 4]
 
diff --git a/test/gc_index_relay_web/controllers/error_json_test.exs b/test/gc_index_relay_web/controllers/error_json_test.exs
index a1a2a2c..f665214 100644
--- a/test/gc_index_relay_web/controllers/error_json_test.exs
+++ b/test/gc_index_relay_web/controllers/error_json_test.exs
@@ -1,6 +1,8 @@
 defmodule GcIndexRelayWeb.ErrorJSONTest do
   use GcIndexRelayWeb.ConnCase, async: true
 
+  @moduletag :unit
+
   test "renders 404" do
     assert GcIndexRelayWeb.ErrorJSON.render("404.json", %{}) == %{errors: %{detail: "Not Found"}}
   end
diff --git a/test/gc_index_relay_web/controllers/filter_controller_test.exs b/test/gc_index_relay_web/controllers/filter_controller_test.exs
index 8b66944..e7e1aa5 100644
--- a/test/gc_index_relay_web/controllers/filter_controller_test.exs
+++ b/test/gc_index_relay_web/controllers/filter_controller_test.exs
@@ -80,6 +80,24 @@ defmodule GcIndexRelayWeb.FilterControllerTest do
       assert hd(events)["id"] == tagged_pub_event.id
     end
 
+    test "filters by uppercase P tag separately from lowercase p (NIP-22)", %{conn: conn} do
+      upper = valid_pub_event_fixture(%{tags: [["P", "abc123def456"]]})
+      {:ok, _} = GcIndexRelay.Nostr.create_event(upper)
+
+      lower = valid_pub_event_fixture(%{tags: [["p", "abc123def456"]], keypair: :keypair2})
+      {:ok, _} = GcIndexRelay.Nostr.create_event(lower)
+
+      event_fixture(%{kind: 2, created_at: 1_640_000_002})
+
+      conn_p = get(conn, ~p"/api/events?since=0&until=9999999999&limit=10&p=abc123def456")
+      assert %{"data" => p_events} = json_response(conn_p, 200)
+      assert Enum.map(p_events, & &1["id"]) == [lower.id]
+
+      conn_upper_p = get(conn, ~p"/api/events?since=0&until=9999999999&limit=10&P=abc123def456")
+      assert %{"data" => p_upper_events} = json_response(conn_upper_p, 200)
+      assert Enum.map(p_upper_events, & &1["id"]) == [upper.id]
+    end
+
     test "respects limit parameter", %{conn: conn} do
       event_fixture(%{kind: 1})
       event_fixture(%{kind: 2, created_at: 1_640_000_001})
@@ -239,6 +257,34 @@ defmodule GcIndexRelayWeb.FilterControllerTest do
       assert hd(events)["id"] == tagged_pub_event.id
     end
 
+    test "POST filter #P matches uppercase P tag only, not lowercase p", %{conn: conn} do
+      upper = valid_pub_event_fixture(%{tags: [["P", "abc123def456"]]})
+      {:ok, _} = GcIndexRelay.Nostr.create_event(upper)
+
+      lower = valid_pub_event_fixture(%{tags: [["p", "abc123def456"]], keypair: :keypair2})
+      {:ok, _} = GcIndexRelay.Nostr.create_event(lower)
+
+      event_fixture(%{kind: 2, created_at: 1_640_000_002})
+
+      conn_upper_p =
+        post(conn, ~p"/api/events/filter", %{
+          "#P" => ["abc123def456"],
+          "limit" => 10
+        })
+
+      assert %{"data" => p_upper} = json_response(conn_upper_p, 200)
+      assert Enum.map(p_upper, & &1["id"]) == [upper.id]
+
+      conn_p =
+        post(conn, ~p"/api/events/filter", %{
+          "#p" => ["abc123def456"],
+          "limit" => 10
+        })
+
+      assert %{"data" => p_lower} = json_response(conn_p, 200)
+      assert Enum.map(p_lower, & &1["id"]) == [lower.id]
+    end
+
     test "respects limit parameter", %{conn: conn} do
       event_fixture(%{kind: 1})
       event_fixture(%{kind: 2, created_at: 1_640_000_001})
diff --git a/test/support/conn_case.ex b/test/support/conn_case.ex
index 3d9a99d..91c2b61 100644
--- a/test/support/conn_case.ex
+++ b/test/support/conn_case.ex
@@ -32,7 +32,28 @@ defmodule GcIndexRelayWeb.ConnCase do
   end
 
   setup tags do
-    GcIndexRelay.DataCase.setup_sandbox(tags)
-    {:ok, conn: Phoenix.ConnTest.build_conn()}
+    sandbox_owner = GcIndexRelay.DataCase.setup_sandbox(tags)
+
+    conn =
+      Phoenix.ConnTest.build_conn()
+      |> maybe_put_sql_sandbox_user_agent(sandbox_owner)
+
+    {:ok, conn: conn}
+  end
+
+  defp maybe_put_sql_sandbox_user_agent(conn, nil), do: conn
+
+  defp maybe_put_sql_sandbox_user_agent(conn, owner) when is_pid(owner) do
+    if Application.get_env(:gc_index_relay, :sql_sandbox, false) do
+      metadata = Phoenix.Ecto.SQL.Sandbox.metadata_for(GcIndexRelay.Repo, owner)
+
+      Plug.Conn.put_req_header(
+        conn,
+        "user-agent",
+        Phoenix.Ecto.SQL.Sandbox.encode_metadata(metadata)
+      )
+    else
+      conn
+    end
   end
 end
diff --git a/test/support/data_case.ex b/test/support/data_case.ex
index 659565d..666b19f 100644
--- a/test/support/data_case.ex
+++ b/test/support/data_case.ex
@@ -28,21 +28,35 @@ defmodule GcIndexRelay.DataCase do
   end
 
   setup tags do
-    GcIndexRelay.DataCase.setup_sandbox(tags)
+    _ = GcIndexRelay.DataCase.setup_sandbox(tags)
     :ok
   end
 
   @doc """
-  Sets up the sandbox based on the test tags.
+  Starts a sandbox owner for the Repo when it is started in this environment.
+
+  Returns the sandbox owner pid when the Repo is started, otherwise `nil`.
   """
-  def setup_sandbox(tags) do
-    # Only set up sandbox if Repo was started
+  @spec setup_sandbox(map()) :: pid() | nil
+  def setup_sandbox(_tags) do
     if Application.get_env(:gc_index_relay, :start_repo, true) do
-      pid = Ecto.Adapters.SQL.Sandbox.start_owner!(GcIndexRelay.Repo, shared: not tags[:async])
+      # Always use shared: false so concurrent test *modules* (ExUnit default) do not
+      # clobber each other via `mode(repo, {:shared, _})`. The test process is allowed on
+      # the owner checkout; HTTP tests rely on `Phoenix.Ecto.SQL.Sandbox` + metadata header.
+      pid = Ecto.Adapters.SQL.Sandbox.start_owner!(GcIndexRelay.Repo, shared: false)
       on_exit(fn -> Ecto.Adapters.SQL.Sandbox.stop_owner(pid) end)
+      empty_nostr_event_tables!(GcIndexRelay.Repo)
+      pid
     end
   end
 
+  defp empty_nostr_event_tables!(repo) do
+    alias GcIndexRelay.Nostr.{Event, Tag}
+
+    _ = repo.delete_all(Tag)
+    _ = repo.delete_all(Event)
+  end
+
   @doc """
   A helper that transforms changeset errors into a map of messages.
 
diff --git a/test/support/fixtures/nostr_fixtures.ex b/test/support/fixtures/nostr_fixtures.ex
index 8b81b6c..c0b8b02 100644
--- a/test/support/fixtures/nostr_fixtures.ex
+++ b/test/support/fixtures/nostr_fixtures.ex
@@ -153,6 +153,42 @@ defmodule GcIndexRelay.NostrFixtures do
     })
   end
 
+  @doc """
+  Returns a real kind `1111` note with many tags (`E`/`P`/`K`/`e`/`k`/`p`/`client`) and a valid NIP-01 id and Schnorr signature.
+
+  Use for tag-parsing, filter, and crypto regression tests. Captured from the network as a known-good vector.
+  """
+  def reference_kind1111_pub_event do
+    %PubEvent{
+      id: "ec42b22bcf5e9b7849ee951e0b55c8c9c1467ac694c8087eabf2bf0a7f6c035f",
+      pubkey: "dd664d5e4016433a8cd69f005ae1480804351789b59de5af06276de65633d319",
+      created_at: 1_775_829_401,
+      kind: 1111,
+      content: "Ganz brav komprimiert, versprochen. Habe mir extra eine App dafür besorgt.",
+      sig:
+        "8f5323d967074351f459e562b66ebb7fc16b505b7dec6a979b6b50ce661f6c51e523215e2bc5afd048ed8b5914ba5e2f3ec4562032e971209579a6a9d2516c82",
+      tags: [
+        [
+          "E",
+          "6e35ec65661c5e2c453f9585a785b3f082c1daf9f769b3bb208af5459d178fca",
+          "wss://nostr.land/",
+          "dd664d5e4016433a8cd69f005ae1480804351789b59de5af06276de65633d319"
+        ],
+        ["P", "dd664d5e4016433a8cd69f005ae1480804351789b59de5af06276de65633d319"],
+        ["K", "21"],
+        [
+          "e",
+          "6e35ec65661c5e2c453f9585a785b3f082c1daf9f769b3bb208af5459d178fca",
+          "wss://nostr.land/",
+          "dd664d5e4016433a8cd69f005ae1480804351789b59de5af06276de65633d319"
+        ],
+        ["k", "21"],
+        ["p", "dd664d5e4016433a8cd69f005ae1480804351789b59de5af06276de65633d319"],
+        ["client", "imwald"]
+      ]
+    }
+  end
+
   # Private helpers
 
   defp compute_event_id(event) do