elixir-webrtc · sgfn · Jun 16, 2026 · May 29, 2026
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -6,8 +6,8 @@ jobs:
     name: lint OTP ${{matrix.otp}} / Elixir ${{matrix.elixir}}
     strategy:
       matrix:
-        otp: ['26']
-        elixir: ['1.15']
+        otp: ['29']
+        elixir: ['1.20']
     steps:
       - uses: actions/checkout@v2
       - uses: erlef/setup-beam@v1
@@ -24,8 +24,8 @@ jobs:
     name: test OTP ${{matrix.otp}} / Elixir ${{matrix.elixir}}
     strategy:
       matrix:
-        otp: ['26']
-        elixir: ['1.15']
+        otp: ['29']
+        elixir: ['1.20']
     env:
       MIX_ENV: test
       GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -39,4 +39,4 @@ jobs:
       - run: mix coveralls.json
       - uses: codecov/codecov-action@v4
         with:
-          token: ${{ secrets.CODECOV_TOKEN }}
+          token: ${{ secrets.CODECOV_TOKEN }}
diff --git a/lib/ex_ice/ice_agent.ex b/lib/ex_ice/ice_agent.ex
@@ -164,7 +164,7 @@ defmodule ExICE.ICEAgent do
   @doc """
   Gets agent's role.
   """
-  @spec get_role(pid()) :: ExICE.Agent.t() | nil
+  @spec get_role(pid()) :: role() | nil
   def get_role(ice_agent) do
     GenServer.call(ice_agent, :get_role)
   end

diff --git a/lib/ex_ice/priv/candidate_pair.ex b/lib/ex_ice/priv/candidate_pair.ex
@@ -1,6 +1,5 @@
 defmodule ExICE.Priv.CandidatePair do
   @moduledoc false
-  require Logger
 
   alias ExICE.Priv.{Candidate, Utils}
 
@@ -62,8 +61,9 @@ defmodule ExICE.Priv.CandidatePair do
               ]
 
   @doc false
-  @spec new(Candidate.t(), Candidate.t(), ExICE.ICEAgent.role(), state(), valid?: boolean()) ::
-          t()
+  @spec new(Candidate.t(), Candidate.t(), ExICE.ICEAgent.role(), state(), [
+          {:valid?, boolean()} | {:last_seen, integer()}
+        ]) :: t()
   def new(local_cand, remote_cand, agent_role, state, opts \\ []) do
     priority = priority(agent_role, local_cand.base.priority, remote_cand.priority)
 
@@ -94,8 +94,8 @@ defmodule ExICE.Priv.CandidatePair do
 
   @doc false
   @spec recompute_priority(t(), integer(), integer(), ExICE.ICEAgent.role()) :: t()
-  def recompute_priority(pair, local_cand_prio, remote_cand_prio, role) do
-    %__MODULE__{pair | priority: priority(role, local_cand_prio, remote_cand_prio)}
+  def recompute_priority(%__MODULE__{} = pair, local_cand_prio, remote_cand_prio, role) do
+    %{pair | priority: priority(role, local_cand_prio, remote_cand_prio)}
   end
 
   @doc false

diff --git a/lib/ex_ice/priv/checklist.ex b/lib/ex_ice/priv/checklist.ex
@@ -96,9 +96,9 @@ defmodule ExICE.Priv.Checklist do
 
   @spec timeout_pairs(t(), [integer()]) :: t()
   def timeout_pairs(checklist, ids) do
-    for {_id, pair} <- checklist, into: %{} do
+    for {_id, %CandidatePair{} = pair} <- checklist, into: %{} do
       if pair.id in ids do
-        {pair.id, %CandidatePair{pair | valid?: false, state: :failed}}
+        {pair.id, %{pair | valid?: false, state: :failed}}
       else
         {pair.id, pair}
       end

diff --git a/lib/ex_ice/priv/conn_check_handler/controlled.ex b/lib/ex_ice/priv/conn_check_handler/controlled.ex
@@ -24,17 +24,17 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlled do
 
       nil when ice_agent.state in [:new, :checking, :connected] ->
         Logger.debug("Adding new candidate pair: #{inspect(pair)}")
-        pair = %CandidatePair{pair | requests_received: 1}
+        pair = %{pair | requests_received: 1}
         checklist = Map.put(ice_agent.checklist, pair.id, pair)
-        ice_agent = %ICEAgent{ice_agent | checklist: checklist}
+        ice_agent = %{ice_agent | checklist: checklist}
         ICEAgent.send_binding_success_response(ice_agent, pair, msg)
 
       %CandidatePair{} = checklist_pair ->
         cond do
           ice_agent.state == :failed ->
             r_pair = resolve_pair(ice_agent, checklist_pair)
 
-            r_pair = %CandidatePair{
+            r_pair = %{
               r_pair
               | last_seen: pair.last_seen,
                 requests_received: r_pair.requests_received + 1
@@ -45,7 +45,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlled do
           checklist_pair.state == :failed and ice_agent.state == :completed ->
             r_pair = resolve_pair(ice_agent, checklist_pair)
 
-            r_pair = %CandidatePair{
+            r_pair = %{
               r_pair
               | last_seen: pair.last_seen,
                 requests_received: r_pair.requests_received + 1
@@ -56,7 +56,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlled do
           checklist_pair.state == :failed ->
             r_pair = resolve_pair(ice_agent, checklist_pair)
 
-            r_pair = %CandidatePair{
+            r_pair = %{
               r_pair
               | state: :waiting,
                 last_seen: pair.last_seen,
@@ -69,7 +69,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlled do
           true ->
             r_pair = resolve_pair(ice_agent, checklist_pair)
 
-            r_pair = %CandidatePair{
+            r_pair = %{
               r_pair
               | last_seen: pair.last_seen,
                 requests_received: r_pair.requests_received + 1
@@ -98,16 +98,16 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlled do
         successful conn check: #{inspect(pair.id)}\
         """)
 
-        pair = %CandidatePair{pair | nominate?: true, requests_received: 1}
+        pair = %{pair | nominate?: true, requests_received: 1}
         checklist = Map.put(ice_agent.checklist, pair.id, pair)
 
-        ice_agent = %ICEAgent{ice_agent | checklist: checklist}
+        ice_agent = %{ice_agent | checklist: checklist}
         ICEAgent.send_binding_success_response(ice_agent, pair, msg)
 
       %CandidatePair{state: :succeeded} = checklist_pair when ice_agent.state != :failed ->
         discovered_pair = Map.fetch!(ice_agent.checklist, checklist_pair.discovered_pair_id)
 
-        discovered_pair = %CandidatePair{
+        discovered_pair = %{
           discovered_pair
           | last_seen: pair.last_seen,
             requests_received: discovered_pair.requests_received + 1
@@ -133,7 +133,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlled do
         Pair: #{inspect(pair.id)}
         """)
 
-        r_pair = %CandidatePair{
+        r_pair = %{
           r_pair
           | nominate?: true,
             last_seen: pair.last_seen,
@@ -151,7 +151,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlled do
         Pair: #{inspect(checklist_pair.id)}
         """)
 
-        checklist_pair = %CandidatePair{
+        checklist_pair = %{
           checklist_pair
           | nominate?: true,
             last_seen: pair.last_seen,
@@ -164,7 +164,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlled do
       %CandidatePair{} = checklist_pair ->
         r_pair = resolve_pair(ice_agent, checklist_pair)
 
-        r_pair = %CandidatePair{
+        r_pair = %{
           r_pair
           | last_seen: pair.last_seen,
             requests_received: r_pair.requests_received + 1
@@ -182,22 +182,22 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlled do
     Logger.debug("Nomination succeeded, pair: #{pair_id}")
 
     pair = Map.fetch!(ice_agent.checklist, pair_id)
-    pair = %CandidatePair{pair | nominate?: false, nominated?: true}
+    pair = %{pair | nominate?: false, nominated?: true}
 
     checklist = Map.put(ice_agent.checklist, pair.id, pair)
-    ice_agent = %ICEAgent{ice_agent | checklist: checklist}
+    ice_agent = %{ice_agent | checklist: checklist}
 
     cond do
       ice_agent.selected_pair_id == nil ->
         Logger.debug("Selecting pair: #{pair_id}")
 
-        %ICEAgent{
+        %{
           ice_agent
           | selected_pair_id: pair.id,
             selected_candidate_pair_changes: ice_agent.selected_candidate_pair_changes + 1
         }
 
-      ice_agent.selected_pair_id != nil and pair.id != ice_agent.selected_pair_id ->
+      pair.id != ice_agent.selected_pair_id ->
         selected_pair = Map.fetch!(ice_agent.checklist, ice_agent.selected_pair_id)
 
         if pair.priority >= selected_pair.priority do
@@ -206,7 +206,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlled do
           New pair: #{pair_id}, old pair: #{ice_agent.selected_pair_id}.\
           """)
 
-          %ICEAgent{
+          %{
             ice_agent
             | selected_pair_id: pair.id,
               selected_candidate_pair_changes: ice_agent.selected_candidate_pair_changes + 1

diff --git a/lib/ex_ice/priv/conn_check_handler/controlling.ex b/lib/ex_ice/priv/conn_check_handler/controlling.ex
@@ -36,17 +36,17 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlling do
 
       nil when ice_agent.state in [:new, :checking, :connected] ->
         Logger.debug("Adding new candidate pair: #{inspect(pair)}")
-        pair = %CandidatePair{pair | requests_received: 1}
+        pair = %{pair | requests_received: 1}
         checklist = Map.put(ice_agent.checklist, pair.id, pair)
-        ice_agent = %ICEAgent{ice_agent | checklist: checklist}
+        ice_agent = %{ice_agent | checklist: checklist}
         ICEAgent.send_binding_success_response(ice_agent, pair, msg)
 
       %CandidatePair{} = checklist_pair ->
         cond do
           ice_agent.state == :failed ->
             r_pair = resolve_pair(ice_agent, checklist_pair)
 
-            r_pair = %CandidatePair{
+            r_pair = %{
               r_pair
               | last_seen: pair.last_seen,
                 requests_received: r_pair.requests_received + 1
@@ -57,7 +57,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlling do
           checklist_pair.state == :failed and ice_agent.state == :completed ->
             r_pair = resolve_pair(ice_agent, checklist_pair)
 
-            r_pair = %CandidatePair{
+            r_pair = %{
               r_pair
               | last_seen: pair.last_seen,
                 requests_received: r_pair.requests_received + 1
@@ -68,7 +68,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlling do
           checklist_pair.state == :failed ->
             r_pair = resolve_pair(ice_agent, checklist_pair)
 
-            r_pair = %CandidatePair{
+            r_pair = %{
               r_pair
               | state: :waiting,
                 last_seen: pair.last_seen,
@@ -81,7 +81,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlling do
           true ->
             r_pair = resolve_pair(ice_agent, checklist_pair)
 
-            r_pair = %CandidatePair{
+            r_pair = %{
               r_pair
               | last_seen: pair.last_seen,
                 requests_received: r_pair.requests_received + 1
@@ -106,21 +106,21 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlling do
     Logger.debug("Nomination succeeded. Selecting pair: #{inspect(pair_id)}")
 
     pair = Map.fetch!(ice_agent.checklist, pair_id)
-    pair = %CandidatePair{pair | nominate?: false, nominated?: true}
+    pair = %{pair | nominate?: false, nominated?: true}
     ice_agent = put_in(ice_agent.checklist[pair.id], pair)
 
     ice_agent =
       cond do
         ice_agent.selected_pair_id == nil ->
           Logger.debug("Selecting pair: #{pair_id}")
 
-          %ICEAgent{
+          %{
             ice_agent
             | selected_pair_id: pair.id,
               selected_candidate_pair_changes: ice_agent.selected_candidate_pair_changes + 1
           }
 
-        ice_agent.selected_pair_id != nil and pair.id != ice_agent.selected_pair_id ->
+        pair.id != ice_agent.selected_pair_id ->
           selected_pair = Map.fetch!(ice_agent.checklist, ice_agent.selected_pair_id)
 
           if pair.priority >= selected_pair.priority do
@@ -129,7 +129,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlling do
             New pair: #{pair_id}, old pair: #{ice_agent.selected_pair_id}.\
             """)
 
-            %ICEAgent{
+            %{
               ice_agent
               | selected_pair_id: pair.id,
                 selected_candidate_pair_changes: ice_agent.selected_candidate_pair_changes + 1
@@ -150,7 +150,7 @@ defmodule ExICE.Priv.ConnCheckHandler.Controlling do
       Logger.warning("Nomination succeeded but checklist hasn't finished.")
     end
 
-    %ICEAgent{ice_agent | nominating?: {false, nil}}
+    %{ice_agent | nominating?: {false, nil}}
   end
 
   defp resolve_pair(ice_agent, pair) do

diff --git a/lib/ex_ice/priv/gatherer.ex b/lib/ex_ice/priv/gatherer.ex
@@ -10,6 +10,8 @@ defmodule ExICE.Priv.Gatherer do
 
   require Logger
 
+  @type local_preferences :: %{:inet.ip_address() => non_neg_integer()}
+
   @type t() :: %__MODULE__{
           if_discovery_module: module(),
           transport_module: module(),
@@ -95,9 +97,8 @@ defmodule ExICE.Priv.Gatherer do
     end)
   end
 
-  @spec gather_host_candidates(t(), %{:inet.ip_address() => non_neg_integer()}, [
-          {Transport.socket(), map()}
-        ]) :: [Candidate.t()]
+  @spec gather_host_candidates(t(), local_preferences(), [{Transport.socket(), map()}]) ::
+          {local_preferences(), [Candidate.t()]}
   def gather_host_candidates(gatherer, local_preferences, sockets) do
     {local_preferences, cands} =
       Enum.reduce(sockets, {local_preferences, []}, fn socket, {local_preferences, cands} ->