diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 6f7fbee..bbed24e 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -14,17 +14,50 @@ jobs:
     runs-on: ${{ matrix.os }}
 
     strategy:
+      fail-fast: false
       matrix:
-        otp_version: ['24', '23', '22', '21']
-        os: [ubuntu-latest]
+        include:
+          - otp_version: 25
+            os: ubuntu-22.04
+            rebar3_version: 3.22
+          - otp_version: 24
+            os: ubuntu-22.04
+            rebar3_version: 3.22
+          - otp_version: 23
+            os: ubuntu-20.04
+            rebar3_version: 3.18
+          - otp_version: 22
+            os: ubuntu-20.04
+            rebar3_version: 3.18
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
 
     - uses: erlef/setup-beam@v1
+      id: setup-beam
       with:
         otp-version: ${{ matrix.otp_version }}
-        rebar3-version: '3.14'
+        rebar3-version: ${{ matrix.rebar3_version }}
+
+    - name: Restore _build
+      uses: actions/cache@v3
+      with:
+        path: _build
+        key: "_build-cache-for\
+              -os-${{ matrix.os }}\
+              -otp-${{ steps.setup-beam.outputs.otp-version }}\
+              -rebar3-${{ steps.setup-beam.outputs.rebar3-version }}\
+              -hash-${{ hashFiles('rebar.lock') }}"
+
+    - name: Restore rebar3's cache
+      uses: actions/cache@v3
+      with:
+        path: ~/.cache/rebar3
+        key: "rebar3-cache-for\
+              -os-${{ matrix.os }}\
+              -otp-${{ steps.setup-beam.outputs.otp-version }}\
+              -rebar3-${{ steps.setup-beam.outputs.rebar3-version }}\
+              -hash-${{ hashFiles('rebar.lock') }}"
 
     - name: Compile
       run: rebar3 compile
@@ -36,9 +69,8 @@ jobs:
       run: rebar3 xref
 
     - name: Covertool
-      if: ${{ always() }}
       run: rebar3 covertool generate
-    - uses: codecov/codecov-action@v1
+    - uses: codecov/codecov-action@v4
       with:
-        file: _build/test/covertool/elli.covertool.xml
+        files: _build/test/covertool/elli.covertool.xml
         env_vars: OTP_VERSION
diff --git a/rebar.config b/rebar.config
index 07ba484..706b4e0 100644
--- a/rebar.config
+++ b/rebar.config
@@ -1,9 +1,7 @@
 {erl_first_files, ["src/elli_handler.erl"]}.
 {erl_opts, [debug_info,
-            {i, "include"},
-            {platform_define, "^2", binary_http_uri},
-            {platform_define, "^2[1-9]", post20}]}.
-{minimum_otp_vsn, "20.0"}.
+            {i, "include"}]}.
+{minimum_otp_vsn, "22.0"}.
 {deps, []}.
 {xref_checks, [undefined_function_calls,locals_not_used]}.
 {profiles, [
@@ -25,11 +23,11 @@
 {shell, [{script_file, "bin/shell.escript"}]}.
 
 {project_plugins, [
-  {covertool, "2.0.3"},
-  {rebar3_lint, "v0.1.10"}
+  {covertool, "2.0.3"}%,
+  %{rebar3_lint, "v0.1.10"}
 ]}.
 
-{provider_hooks, [{pre, [{eunit, lint}]}]}.
+%{provider_hooks, [{pre, [{eunit, lint}]}]}.
 {dialyzer, [{plt_extra_apps, [ssl]}]}.
 
 {cover_enabled, true}.
diff --git a/src/elli_http.erl b/src/elli_http.erl
index 4404a76..cd549e4 100644
--- a/src/elli_http.erl
+++ b/src/elli_http.erl
@@ -323,17 +323,17 @@ execute_callback(#req{callback = {Mod, Args}} = Req) ->
     catch
         throw:{ResponseCode, Headers, Body} when is_integer(ResponseCode) ->
             {response, ResponseCode, Headers, Body};
-        ?WITH_STACKTRACE(throw, Exc, Stacktrace)
+        throw:Exc:Stacktrace ->
             handle_event(Mod, request_throw,
                          [Req, Exc, Stacktrace],
                          Args),
             {response, 500, [], <<"Internal server error">>};
-        ?WITH_STACKTRACE(error, Error, Stacktrace)
+        error:Error:Stacktrace ->
             handle_event(Mod, request_error,
                          [Req, Error, Stacktrace],
                          Args),
             {response, 500, [], <<"Internal server error">>};
-        ?WITH_STACKTRACE(exit, Exit, Stacktrace)
+        exit:Exit:Stacktrace ->
             handle_event(Mod, request_exit,
                          [Req, Exit, Stacktrace],
                          Args),
@@ -708,7 +708,6 @@ is_header_defined(Key, Headers) ->
 get_header(Key, Headers) ->
     get_header(Key, Headers, undefined).
 
--ifdef(OTP_RELEASE).
 get_header(Key, Headers, Default) ->
     CaseFoldedKey = string:casefold(Key),
     case lists:search(fun({N, _}) -> string:equal(CaseFoldedKey, N, true) end, Headers) of
@@ -717,68 +716,23 @@ get_header(Key, Headers, Default) ->
         false ->
             Default
     end.
--else.
-get_header(Key, Headers, Default) ->
-    CaseFoldedKey = string:casefold(Key),
-    case search(fun({N, _}) -> string:equal(CaseFoldedKey, N, true) end, Headers) of
-        {value, {_, Value}} ->
-            Value;
-        false ->
-            Default
-    end.
-
-search(Pred, [Hd|Tail]) ->
-    case Pred(Hd) of
-        true -> {value, Hd};
-        false -> search(Pred, Tail)
-    end;
-search(Pred, []) when is_function(Pred, 1) ->
-    false.
--endif.
 
 %%
 %% PATH HELPERS
 %%
 
--ifdef(OTP_RELEASE).
-  -if(?OTP_RELEASE >= 22).
-    parse_path({abs_path, FullPath}) ->
-        URIMap = uri_string:parse(FullPath),
-        Host = maps:get(host, URIMap, undefined),
-        Scheme = maps:get(scheme, URIMap, undefined),
-        Path = maps:get(path, URIMap, <<>>),
-        Query = maps:get(query, URIMap, <<>>),
-        Port = maps:get(port, URIMap, case Scheme of http -> 80; https -> 443; _ -> undefined end),
-        {ok, {Scheme, Host, Port}, {Path, split_path(Path), uri_string:dissect_query(Query)}};
-    parse_path({absoluteURI, Scheme, Host, Port, Path}) ->
-        setelement(2, parse_path({abs_path, Path}), {Scheme, Host, Port});
-    parse_path(_) ->
-        {error, unsupported_uri}.
-  -else.
-    parse_path({abs_path, FullPath}) ->
-        Parsed = case binary:split(FullPath, [<<"?">>]) of
-                     [URL]       -> {FullPath, split_path(URL), []};
-                     [URL, Args] -> {FullPath, split_path(URL), split_args(Args)}
-                 end,
-        {ok, {undefined, undefined, undefined}, Parsed};
-    parse_path({absoluteURI, Scheme, Host, Port, Path}) ->
-        setelement(2, parse_path({abs_path, Path}), {Scheme, Host, Port});
-    parse_path(_) ->
-        {error, unsupported_uri}.
-  -endif.
--else.
-  %% same as else branch above. can drop this when only OTP 21+ is supported
-  parse_path({abs_path, FullPath}) ->
-      Parsed = case binary:split(FullPath, [<<"?">>]) of
-                   [URL]       -> {FullPath, split_path(URL), []};
-                   [URL, Args] -> {FullPath, split_path(URL), split_args(Args)}
-               end,
-      {ok, {undefined, undefined, undefined}, Parsed};
-  parse_path({absoluteURI, Scheme, Host, Port, Path}) ->
-      setelement(2, parse_path({abs_path, Path}), {Scheme, Host, Port});
-  parse_path(_) ->
-      {error, unsupported_uri}.
--endif.
+parse_path({abs_path, FullPath}) ->
+    URIMap = uri_string:parse(FullPath),
+    Host = maps:get(host, URIMap, undefined),
+    Scheme = maps:get(scheme, URIMap, undefined),
+    Path = maps:get(path, URIMap, <<>>),
+    Query = maps:get(query, URIMap, <<>>),
+    Port = maps:get(port, URIMap, case Scheme of http -> 80; https -> 443; _ -> undefined end),
+    {ok, {Scheme, Host, Port}, {Path, split_path(Path), uri_string:dissect_query(Query)}};
+parse_path({absoluteURI, Scheme, Host, Port, Path}) ->
+    setelement(2, parse_path({abs_path, Path}), {Scheme, Host, Port});
+parse_path(_) ->
+    {error, unsupported_uri}.
 
 split_path(Path) ->
     [P || P <- binary:split(Path, [<<"/">>], [global]),
@@ -813,7 +767,7 @@ handle_event(Mod, Name, EventArgs, ElliArgs) ->
     try
         Mod:handle_event(Name, EventArgs, ElliArgs)
     catch
-        ?WITH_STACKTRACE(EvClass, EvError, Stacktrace)
+        EvClass:EvError:Stacktrace ->
             ?LOG_ERROR("~p:handle_event/3 crashed ~p:~p~n~p",
                        [Mod, EvClass, EvError, Stacktrace])
     end.
diff --git a/src/elli_tcp.erl b/src/elli_tcp.erl
index ee9ad39..b0f3fdc 100644
--- a/src/elli_tcp.erl
+++ b/src/elli_tcp.erl
@@ -42,7 +42,6 @@ accept({ssl, Socket}, Server, Timeout) ->
             {error, Reason}
     end.
 
--ifdef(post20).
 handshake(S, Server, Timeout) ->
     case ssl:handshake(S, Timeout) of
         {ok, S1} ->
@@ -53,18 +52,6 @@ handshake(S, Server, Timeout) ->
         {error, Reason} ->
             {error, Reason}
     end.
--else.
-handshake(S, Server, Timeout) ->
-    case ssl:ssl_accept(S, Timeout) of
-        ok ->
-            gen_server:cast(Server, accepted),
-            {ok, {ssl, S}};
-        {error, closed} ->
-            {error, econnaborted};
-        {error, Reason} ->
-            {error, Reason}
-    end.
--endif.
 
 recv({plain, Socket}, Size, Timeout) ->
     gen_tcp:recv(Socket, Size, Timeout);
diff --git a/src/elli_util.hrl b/src/elli_util.hrl
index 557ec28..e844c95 100644
--- a/src/elli_util.hrl
+++ b/src/elli_util.hrl
@@ -1,17 +1,4 @@
-
--ifdef(OTP_RELEASE).
 -include_lib("kernel/include/logger.hrl").
--else.
--define(LOG_ERROR(Str), error_logger:error_msg(Str)).
--define(LOG_ERROR(Format,Data), error_logger:error_msg(Format, Data)).
--define(LOG_INFO(Format,Data), error_logger:info_msg(Format, Data)).
--endif.
-
--ifdef(OTP_RELEASE).
--define(WITH_STACKTRACE(T, R, S), T:R:S ->).
--else.
--define(WITH_STACKTRACE(T, R, S), T:R -> S = erlang:get_stacktrace(),).
--endif.
 
 %% Bloody useful
 -define(IF(Test,True,False), case Test of true -> True; false -> False end).
diff --git a/test/elli_tests.erl b/test/elli_tests.erl
index c89ba17..fb62ed1 100644
--- a/test/elli_tests.erl
+++ b/test/elli_tests.erl
@@ -7,13 +7,7 @@
 -define(VTB(T1, T2, LB, UB),
         time_diff_to_micro_seconds(T1, T2) >= LB andalso
         time_diff_to_micro_seconds(T1, T2) =< UB).
--ifdef(OTP_RELEASE).
 -include_lib("kernel/include/logger.hrl").
--else.
--define(LOG_ERROR(Str), error_logger:error_msg(Str)).
--define(LOG_ERROR(Format,Data), error_logger:error_msg(Format, Data)).
--define(LOG_INFO(Format,Data), error_logger:info_msg(Format, Data)).
--endif.
 
 time_diff_to_micro_seconds(T1, T2) ->
     erlang:convert_time_unit(