diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 72ddfe11..33295aec 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -33,20 +33,6 @@ jobs:
         - otp_version: 21
           send_coverage: true
           run_dialyzer: true
-          build_docs: true
-
-        - otp_version: 20
-
-        - otp_version: 19
-
-        - otp_version: 19
-          erl_hist: true
-
-        - otp_version: 18
-          # old_rebar fails with "Package not found in registry: {<<"hdr_histogram">>,<<"0.5.0">>}."
-          # with hdr_histogram NIF: xprof_core_hist_SUITE: Segmentation fault (core dumped)
-          erl_hist: true
-          old_cowboy: true
 
     steps:
     - uses: actions/checkout@v3
@@ -72,57 +58,112 @@ jobs:
       run: make dialyzer
       timeout-minutes: 8
 
-    - if: matrix.build_docs
-      run: make doc
-
     - if: matrix.send_coverage && success()
       run: ./rebar3 as test coveralls send
       env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       continue-on-error: true
 
-  test_json_lib:
-    name: Test different json lib (${{ matrix.json_lib }} | OTP ${{ matrix.otp_version }})
+  # Same as the "test" job but for OTP 18-20, whose containers ship a glibc
+  # too old for the node20 runtime that actions/checkout and actions/cache
+  # now require. This job checks out with plain git and skips the cache.
+  test_legacy:
+    name: OTP ${{ matrix.otp_version }} (legacy)
     runs-on: ubuntu-latest
-
     container: erlang:${{ matrix.otp_version }}
 
     strategy:
       fail-fast: false
       matrix:
-        otp_version: [19, 21]
-        json_lib: [jiffy, jsx, thoas]
         include:
+        - otp_version: 20
+
         - otp_version: 19
-          old_cowboy: true
 
-        # thoas requires OTP 21+
         - otp_version: 19
-          json_lib: thoas
-          skip: true
+          erl_hist: true
 
-        # fails with "Package not found in registry: jiffy-1.1.0."
-        #- otp_version: 18
-        #  old_rebar: true
-        #  old_cowboy: true
+        - otp_version: 18
+          # old_rebar fails with "Package not found in registry: {<<"hdr_histogram">>,<<"0.5.0">>}."
+          # with hdr_histogram NIF: xprof_core_hist_SUITE: Segmentation fault (core dumped)
+          erl_hist: true
+          old_cowboy: true
 
     steps:
-    - uses: actions/checkout@v3
+    - name: Checkout with git (avoids node-based actions on old glibc)
+      run: |
+        git config --global --add safe.directory $GITHUB_WORKSPACE
+        git init -q
+        git remote add origin "https://github.com/${{ github.repository }}"
+        git fetch -q --depth 1 origin "${{ github.ref }}"
+        git checkout -q FETCH_HEAD
 
     - if: matrix.old_rebar
       run: echo "REBAR3=./rebar3" >> $GITHUB_ENV
 
+    - if: matrix.erl_hist
+      run: echo "XPROF_ERL_HIST=true" >> $GITHUB_ENV
+
     - if: matrix.old_cowboy
       run: echo "COWBOY_VERSION=1.1.2" >> $GITHUB_ENV
 
+    - run: make test
+
+  test_json_lib:
+    name: Test different json lib (${{ matrix.json_lib }} | OTP ${{ matrix.otp_version }})
+    runs-on: ubuntu-latest
+
+    container: erlang:${{ matrix.otp_version }}
+
+    strategy:
+      fail-fast: false
+      matrix:
+        otp_version: [21]
+        json_lib: [jiffy, jsx, thoas]
+
+    steps:
+    - uses: actions/checkout@v3
+
     - name: Cache hex packages
       uses: actions/cache@v3
       with:
         path: $HOME/.cache/rebar3
         key: ${{ matrix.otp_version }}-rebar3-cache-json-lib
 
-    - if: ${{ !matrix.skip }}
-      run: make test_${{ matrix.json_lib }}
+    - run: make test_${{ matrix.json_lib }}
+
+  test_docs:
+    name: Test generating documentation
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        include:
+          - elixir: 1.15.x
+            otp_version: 26
+            rebar3: '3.22.1'
+            # hdr_histogram NIF requires the below PR to be merged to build on OTP 26
+            # https://github.com/HdrHistogram/hdr_histogram_erl/pull/44
+            erl_hist: true
+
+    steps:
+    - uses: actions/checkout@v3
+    - uses: erlef/setup-beam@v1
+      with:
+        otp-version: ${{matrix.otp_version}}
+        elixir-version: ${{matrix.elixir}}
+        rebar3-version: ${{matrix.rebar3}}
+
+    - if: matrix.erl_hist
+      run: echo "XPROF_ERL_HIST=true" >> $GITHUB_ENV
+
+    - name: Cache hex packages
+      uses: actions/cache@v3
+      with:
+        path: $HOME/.cache/rebar3
+        key: ${{ matrix.otp_version }}-rebar3-cache
+
+    - run: make gen_ex_doc
 
   test_elixir:
     name: Test with Elixir (Elixir ${{matrix.elixir}} | OTP ${{matrix.otp_version}})
@@ -131,60 +172,15 @@ jobs:
       fail-fast: false
       matrix:
         include:
-        # runner ubuntu-20.4 is only compatible with OTP 20+
-        # earlier OTP versions fail with:
-        # no match of right hand side value: {:error, {:ssl, {'no such file or directory', 'ssl.app'}}}
-        # running ubuntu-18.4 was removed on 2022.04.03
-        # https://github.com/actions/runner-images/issues/6002
-        #  - elixir: 1.4.x
-        #    otp_version: 18
-        #    rebar3: '3.7.4'
-        #    old_cowboy: true
-        #    # with hdr_histogram NIF: xprof_core_hist_SUITE: Segmentation fault (core dumped)
-        #    erl_hist: true
-        #    os: ubuntu-18.04
-
-          - elixir: 1.5.x
-            otp_version: 20
-            rebar3: '3.7.4'
-            old_cowboy: true
-            erl_hist: true
-            os: ubuntu-20.04
-
-          - elixir: 1.6.x
-            otp_version: 20
-            rebar3: '3.15.2'
-            os: ubuntu-20.04
-
-          - elixir: 1.7.x
-            otp_version: 20
-            rebar3: '3.15.2'
-            os: ubuntu-20.04
-
-          - elixir: 1.8.x
-            otp_version: 20
-            rebar3: '3.15.2'
-            os: ubuntu-20.04
-
-          - elixir: 1.9.x
-            otp_version: 20
-            rebar3: '3.15.2'
-            os: ubuntu-20.04
-
-          - elixir: 1.10.x
-            otp_version: 21
-            rebar3: '3.15.2'
-            os: ubuntu-20.04
-
-          - elixir: 1.11.x
-            otp_version: 22
+          - elixir: 1.11.4
+            otp_version: 24
             rebar3: '3.18.0'
-            os: ubuntu-20.04
+            os: ubuntu-latest
 
           - elixir: 1.12.x
-            otp_version: 23
+            otp_version: 24
             rebar3: '3.19.0'
-            os: ubuntu-20.04
+            os: ubuntu-latest
 
           - elixir: 1.13.x
             otp_version: 24
diff --git a/Makefile b/Makefile
index 57b0e682..239de544 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,5 @@
 JS_PRIV=apps/xprof_gui/priv
 BIN_DIR:=node_modules/.bin
-VERSION:=$(shell grep vsn apps/xprof/src/xprof.app.src | cut -d '"' -f 2)
 REBAR3?=$(shell which rebar3 || echo ./rebar3)
 
 # this will update cowboy version based on rebar.config overwriting the lock file
@@ -63,16 +62,19 @@ test_thoas:
 doc:
 	$(REBAR3) edoc
 
-~/.mix/escripts/ex_doc:
-	mix escript.install hex ex_doc --force
-
 ./doc/src/readme.md: README.md
 	sed -e 's|(doc/src/querysyntax.md)|(querysyntax.html)|' \
 	    -e 's|doc/assets/|assets/|' \
 	    -e '1 s|\[!\[.*||' README.md > ./doc/src/readme.md
 
-gen_ex_doc: ~/.mix/escripts/ex_doc ./doc/docs.exs ./doc/src/readme.md ./doc/src/querysyntax.md
-	~/.mix/escripts/ex_doc XProf $(VERSION) "doc/ebin" -c ./doc/docs.exs
+gen_ex_doc: ./doc/src/readme.md
+	$(MAYBE_UPDATE_COWBOY)
+	$(MAYBE_UNLOCK_HIST)
+	$(REBAR3) as docs ex_doc --app xprof_core
+	$(REBAR3) as docs ex_doc --app xprof_gui
+	cp _build/docs/lib/xprof_core/ebin/xprof_core.beam _build/docs/lib/xprof/ebin
+	cp _build/docs/lib/xprof_gui/ebin/xprof_gui_rest.beam _build/docs/lib/xprof/ebin
+	$(REBAR3) as docs ex_doc --app xprof
 
 dialyzer:
 	$(MAYBE_UPDATE_COWBOY)
@@ -82,4 +84,7 @@ dialyzer:
 publish:
 	$(REBAR3) as publish hex publish --deps_from_config
 
-.PHONY: compile dev dev_back_end dev_front_end npm bootstrap_front_end test_front_end build_prod_front_end test doc gen_ex_doc dialyzer publish
+publish_docs: gen_ex_doc
+	$(REBAR3) as publish hex docs
+
+.PHONY: compile dev dev_back_end dev_front_end npm bootstrap_front_end test_front_end build_prod_front_end test doc gen_ex_doc dialyzer publish publish_docs
diff --git a/apps/xprof/src/xprof.app.src b/apps/xprof/src/xprof.app.src
index 0b5b5c4f..ee0e06a0 100644
--- a/apps/xprof/src/xprof.app.src
+++ b/apps/xprof/src/xprof.app.src
@@ -11,6 +11,7 @@
  ,{env,[]}
  ,{modules, []}
  ,{files, ["rebar.config", "src/"]}
+ ,{doc, "doc"}
  ,{licenses, ["BSD-3-Clause"]}
  ,{maintainers, ["Marcin Kasprowicz", "Marcin Kolodziej",
                  "Michal Niec", "Pawel Pikula",
diff --git a/apps/xprof_core/src/test_module.erl b/apps/xprof_core/src/test_module.erl
index 0c281e66..842c8997 100644
--- a/apps/xprof_core/src/test_module.erl
+++ b/apps/xprof_core/src/test_module.erl
@@ -1,6 +1,7 @@
 %%% @doc Module to generate sample data
 %%% start tracing on `test_module:expensive_fun/1'
 %%% @end
+%%% @private
 -module(test_module).
 -export([start/0]).
 
diff --git a/apps/xprof_core/src/xprof_core.erl b/apps/xprof_core/src/xprof_core.erl
index f823de48..6726990f 100644
--- a/apps/xprof_core/src/xprof_core.erl
+++ b/apps/xprof_core/src/xprof_core.erl
@@ -1,3 +1,6 @@
+%%%
+%%% @doc Erlang API to core XProf functionality
+%%%
 -module(xprof_core).
 
 -export([%% Autocomplete
@@ -101,6 +104,7 @@ expand_query(Query) ->
     end.
 
 %% @doc Get loaded modules and functions (MFAs) that match the query string.
+%%
 %% Used for autocomplete suggestions on the GUI.
 -spec get_matching_mfas_pp(binary()) -> [MFA :: binary()].
 get_matching_mfas_pp(Query) ->
@@ -116,7 +120,9 @@ monitor_pp(Query) ->
     monitor_pp(Query, []).
 
 %% @doc Start monitoring based on the specified query string with additional
-%% parameters. Additional parameters have precedence overthe same keys in the
+%% parameters.
+%%
+%% Additional parameters have precedence overthe same keys in the
 %% query.
 -spec monitor_pp(binary(), [{binary(), binary()}])
                 -> ok | {error, Reason :: already_traced | string()}.
@@ -145,7 +151,9 @@ get_all_monitored() ->
     xprof_core_tracer:all_monitored().
 
 %% @doc Return metrics gathered for the given function since the given
-%% timestamp. Each item contains a timestamp and the corresponding histogram
+%% timestamp.
+%%
+%% Each item contains a timestamp and the corresponding histogram
 %% metrics values.
 -spec get_data(xprof_core:mfa_id(), timestamp()) -> [Item] | {error, not_found}
   when Item :: [{time, timestamp()} | {HistKey, number()}],
@@ -155,6 +163,8 @@ get_all_monitored() ->
 get_data(MFA, TimeStamp) ->
     xprof_core_trace_handler:data(MFA, TimeStamp).
 
+%% @doc Return metrics gathered for the given function formatted
+%% according to the active syntax mode.
 get_data_pp(MFA, TimeStamp) ->
     case xprof_core_trace_handler:data(MFA, TimeStamp) of
         {error, _} = Error ->
@@ -177,7 +187,7 @@ get_called_funs(MFA) ->
     xprof_core_vm_info:get_called_funs(MFA).
 
 %% @doc Return list of called functions formatted according to the
-%% active syntax mode
+%% active syntax mode.
 -spec get_called_funs_pp(xprof_core:mfa_id()) -> [MFA :: binary()].
 get_called_funs_pp(MFA) ->
     ModeCb = xprof_core_lib:get_mode_cb(),
@@ -188,14 +198,16 @@ get_called_funs_pp(MFA) ->
 %% Global trace status
 %%
 
-%% @doc Turn on tracing for one or all processes. Additionally tracing can be
-%% paused and resumed for the same process specification (one or all) that was
-%% given earlier.
+%% @doc Turn on tracing for one or all processes.
+%%
+%% Additionally tracing can be paused and resumed for the same process
+%% specification (one or all) that was given earlier.
 -spec trace(pid() | all | pause | resume) -> ok.
 trace(PidOrSpec) ->
     xprof_core_tracer:trace(PidOrSpec).
 
 %% @doc Return current tracing state.
+%%
 %% (The `initialized' status is basically the same as `paused', additionally
 %%  meaning that no tracing was started yet since xprof was started)
 -spec get_trace_status() -> {pid() | all, Status :: initialized | running | paused | overflow}.
@@ -239,6 +251,7 @@ get_captured_data_pp(MFA, Offset) ->
             Error
     end.
 
+%% @private
 args_res2proplist({Index, Pid, CallTime, Args, Res}, ModeCb) ->
     [{id, Index},
      {pid, ModeCb:fmt_term(Pid)},
@@ -246,6 +259,7 @@ args_res2proplist({Index, Pid, CallTime, Args, Res}, ModeCb) ->
      {args, ModeCb:fmt_term(Args)},
      {res, format_result(Res, ModeCb)}].
 
+%% @private
 format_result({return_from, Term}, ModeCb) ->
     ModeCb:fmt_term(Term);
 format_result({exception_from, {Class, Reason}}, ModeCb) ->
@@ -284,20 +298,22 @@ rr(Mod) ->
     xprof_core_records:load_records(Mod).
 
 %% @doc Remove all record definitions.
-%% (similar to shell command ```rf('_')''')
+%% (similar to shell command `` rf('_') '')
 -spec rf() -> ok.
 rf() ->
     xprof_core_records:forget_records().
 
-%% @doc Remove selected record definitions. RecNames is a record name or a
-%% list of record names. To remove all record definitions, use '_'.
+%% @doc Remove selected record definitions.
+%%
+%% The argument can be a record name or a list of record names. To
+%% remove all record definitions, use `` '_' ''.
 %% (similar to shell command `rf/1')
 -spec rf(atom() | [atom()]) -> ok.
 rf(RecNameOrNames) ->
     xprof_core_records:forget_records(RecNameOrNames).
 
 %% @doc Return all stored record definitions.
-%% (Similar to shell command `rl()')
+%% (Similar to shell command `rl/0')
 -spec rl() -> [tuple()].
 rl() ->
     xprof_core_records:get_record_defs().
@@ -311,7 +327,9 @@ rl() ->
 set_mode(Mode) ->
     xprof_core_lib:set_mode(Mode).
 
-%% @doc Get syntax mode, if not set explicitly it will be autodetected.
+%% @doc Get syntax mode.
+%%
+%% If not set explicitly it will be autodetected.
 -spec get_mode() -> xprof_core:mode().
 get_mode() ->
     xprof_core_lib:get_mode().
diff --git a/apps/xprof_core/src/xprof_core_app.erl b/apps/xprof_core/src/xprof_core_app.erl
index a43e3798..7606bc50 100644
--- a/apps/xprof_core/src/xprof_core_app.erl
+++ b/apps/xprof_core/src/xprof_core_app.erl
@@ -1,5 +1,6 @@
 %% @doc XProf Core application callback
 %% @end
+%% @private
 -module(xprof_core_app).
 
 -behaviour(application).
diff --git a/apps/xprof_core/src/xprof_core_cmd.erl b/apps/xprof_core/src/xprof_core_cmd.erl
index 714f3d63..46b48693 100644
--- a/apps/xprof_core/src/xprof_core_cmd.erl
+++ b/apps/xprof_core/src/xprof_core_cmd.erl
@@ -8,6 +8,7 @@
 %%% - other -> no trace_pattern -> xprof_core_tracer should find out where to send trace based on trace tag (maybe)
 %%%   -> can only be turned off by trace/3
 %%%   - cmd id = ??? (single tracer per cmd-name or trace tag)
+%%% @private
 -module(xprof_core_cmd).
 
 -export([expand_query/1,
@@ -28,7 +29,7 @@
 
 %% Convert param value from syntax-tree format to Erlang term or expression
 %% (Useful to implement some syntactic sugar/shorthands)
--callback param_from_ast(Key :: atom(), Ast :: erl_parse:syntax_tree()) ->
+-callback param_from_ast(Key :: atom(), Ast :: erl_parse:abstract_expr()) ->
     {ok, Value :: term()} | {error, Reason :: term()}.
 
 %% Validate param value and optionally convert to internal format
diff --git a/apps/xprof_core/src/xprof_core_cmd_argdist.erl b/apps/xprof_core/src/xprof_core_cmd_argdist.erl
index a6c16a4d..78bf48d4 100644
--- a/apps/xprof_core/src/xprof_core_cmd_argdist.erl
+++ b/apps/xprof_core/src/xprof_core_cmd_argdist.erl
@@ -1,3 +1,4 @@
+%% @private
 -module(xprof_core_cmd_argdist).
 
 -behaviour(xprof_core_cmd).
diff --git a/apps/xprof_core/src/xprof_core_cmd_funlatency.erl b/apps/xprof_core/src/xprof_core_cmd_funlatency.erl
index f84b2eca..b3f94676 100644
--- a/apps/xprof_core/src/xprof_core_cmd_funlatency.erl
+++ b/apps/xprof_core/src/xprof_core_cmd_funlatency.erl
@@ -1,3 +1,4 @@
+%% @private
 -module(xprof_core_cmd_funlatency).
 
 -export([mandatory_params/0,
diff --git a/apps/xprof_core/src/xprof_core_elixir_syntax.erl b/apps/xprof_core/src/xprof_core_elixir_syntax.erl
index 6c2cfd8b..ad800589 100644
--- a/apps/xprof_core/src/xprof_core_elixir_syntax.erl
+++ b/apps/xprof_core/src/xprof_core_elixir_syntax.erl
@@ -1,6 +1,7 @@
 %%%
 %%% @doc Module to parse and format expressions in Elixir syntax
 %%%
+%%% @private
 -module(xprof_core_elixir_syntax).
 
 -behaviour(xprof_core_language).
@@ -25,7 +26,7 @@
 
 %% Elixir quoted expressions
 -type ex_quoted() :: tuple() | ex_literal().
--type ex_literal() :: atom() | number() | binary() | fun((...) -> any()) | {any(), any()} | [any()].
+-type ex_literal() :: atom() | number() | binary() | fun() | {any(), any()} | list().
 %% Erlang abstract syntax tree
 -type erl_ast() :: tuple().
 
diff --git a/apps/xprof_core/src/xprof_core_erlang_syntax.erl b/apps/xprof_core/src/xprof_core_erlang_syntax.erl
index 0e74e494..24f66f3e 100644
--- a/apps/xprof_core/src/xprof_core_erlang_syntax.erl
+++ b/apps/xprof_core/src/xprof_core_erlang_syntax.erl
@@ -1,6 +1,7 @@
 %%%
 %%% @doc Module to parse and format expressions in Erlang syntax
 %%%
+%%% @private
 -module(xprof_core_erlang_syntax).
 
 -behaviour(xprof_core_language).
diff --git a/apps/xprof_core/src/xprof_core_hist.erl b/apps/xprof_core/src/xprof_core_hist.erl
index 9f005c4c..279caedf 100644
--- a/apps/xprof_core/src/xprof_core_hist.erl
+++ b/apps/xprof_core/src/xprof_core_hist.erl
@@ -29,6 +29,7 @@
 %%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 %%% SOFTWARE.
 
+%%% @private
 -module(xprof_core_hist).
 
 -export([new/2,
diff --git a/apps/xprof_core/src/xprof_core_language.erl b/apps/xprof_core/src/xprof_core_language.erl
index d759c3d5..4d0118c5 100644
--- a/apps/xprof_core/src/xprof_core_language.erl
+++ b/apps/xprof_core/src/xprof_core_language.erl
@@ -2,6 +2,7 @@
 %%% @doc Callback functions that need to be implemented
 %%% for a language-specific behaviour
 %%%
+%%% @private
 -module(xprof_core_language).
 
 %% Function for start monitoring
@@ -47,7 +48,7 @@
 -callback fmt_param(xprof_core:param_name()) ->
     Formatted :: binary().
 
--callback fmt_param_and_delim(xprof_core:param()) ->
+-callback fmt_param_and_delim(xprof_core:param_name()) ->
     Formatted :: binary().
 
 -callback fmt_exception(Class :: throw | error | exit, Reason :: term()) ->
diff --git a/apps/xprof_core/src/xprof_core_lib.erl b/apps/xprof_core/src/xprof_core_lib.erl
index 2b5cbd6b..8c51cb83 100644
--- a/apps/xprof_core/src/xprof_core_lib.erl
+++ b/apps/xprof_core/src/xprof_core_lib.erl
@@ -1,3 +1,4 @@
+%% @private
 -module(xprof_core_lib).
 
 -export([mfaspec2atom/1,
diff --git a/apps/xprof_core/src/xprof_core_ms.erl b/apps/xprof_core/src/xprof_core_ms.erl
index 2e545382..365e1e98 100644
--- a/apps/xprof_core/src/xprof_core_ms.erl
+++ b/apps/xprof_core/src/xprof_core_ms.erl
@@ -1,3 +1,4 @@
+%% @private
 -module(xprof_core_ms).
 
 -export([fun2ms/1,
diff --git a/apps/xprof_core/src/xprof_core_query.erl b/apps/xprof_core/src/xprof_core_query.erl
index 3a202365..4960e78c 100644
--- a/apps/xprof_core/src/xprof_core_query.erl
+++ b/apps/xprof_core/src/xprof_core_query.erl
@@ -1,3 +1,4 @@
+%% @private
 -module(xprof_core_query).
 
 -export([param_to_term/1,
diff --git a/apps/xprof_core/src/xprof_core_records.erl b/apps/xprof_core/src/xprof_core_records.erl
index 9de09945..4c409c3a 100644
--- a/apps/xprof_core/src/xprof_core_records.erl
+++ b/apps/xprof_core/src/xprof_core_records.erl
@@ -1,4 +1,5 @@
 %%% @doc Server to store loaded record definitions.
+%%% @private
 -module(xprof_core_records).
 
 -export([start_link/0,
diff --git a/apps/xprof_core/src/xprof_core_sup.erl b/apps/xprof_core/src/xprof_core_sup.erl
index c7f1fe9f..02d4f2b3 100644
--- a/apps/xprof_core/src/xprof_core_sup.erl
+++ b/apps/xprof_core/src/xprof_core_sup.erl
@@ -1,4 +1,5 @@
 %% @doc xprof top level supervisor.
+%% @private
 -module(xprof_core_sup).
 
 -behaviour(supervisor).
diff --git a/apps/xprof_core/src/xprof_core_trace_handler.erl b/apps/xprof_core/src/xprof_core_trace_handler.erl
index 705fd27e..b3ca1538 100644
--- a/apps/xprof_core/src/xprof_core_trace_handler.erl
+++ b/apps/xprof_core/src/xprof_core_trace_handler.erl
@@ -5,6 +5,7 @@
 %% registers itself localy under a atom that consists of MFA and xprof_
 %% prefix. The same name is used to create public ETS table that holds entries
 %% with call time stats for every second.
+%% @private
 -module(xprof_core_trace_handler).
 
 -behaviour(gen_server).
diff --git a/apps/xprof_core/src/xprof_core_trace_handler_sup.erl b/apps/xprof_core/src/xprof_core_trace_handler_sup.erl
index 8c1875e9..daa052a4 100644
--- a/apps/xprof_core/src/xprof_core_trace_handler_sup.erl
+++ b/apps/xprof_core/src/xprof_core_trace_handler_sup.erl
@@ -1,4 +1,5 @@
 %%% @doc Supervisor
+%%% @private
 -module(xprof_core_trace_handler_sup).
 
 -behaviour(supervisor).
diff --git a/apps/xprof_core/src/xprof_core_tracer.erl b/apps/xprof_core/src/xprof_core_tracer.erl
index e090464f..01694ffb 100644
--- a/apps/xprof_core/src/xprof_core_tracer.erl
+++ b/apps/xprof_core/src/xprof_core_tracer.erl
@@ -1,5 +1,6 @@
 %% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
 %% ex: ts=4 sw=4 et
+%% @private
 
 -module(xprof_core_tracer).
 
diff --git a/apps/xprof_core/src/xprof_core_vm_info.erl b/apps/xprof_core/src/xprof_core_vm_info.erl
index 4055f5b9..79c18e83 100644
--- a/apps/xprof_core/src/xprof_core_vm_info.erl
+++ b/apps/xprof_core/src/xprof_core_vm_info.erl
@@ -1,3 +1,4 @@
+%% @private
 -module(xprof_core_vm_info).
 
 -include_lib("compiler/src/beam_disasm.hrl").
diff --git a/doc/docs.exs b/doc/docs.exs
deleted file mode 100644
index 4c6fb91b..00000000
--- a/doc/docs.exs
+++ /dev/null
@@ -1,13 +0,0 @@
-[
-  main: "readme",
-  extras: ["doc/src/readme.md",
-           "doc/src/querysyntax.md": [title: "Query Syntax"],
-           "doc/src/commands.md": []
-          ],
-  api_reference: false,
-  output: "doc/html/",
-  assets: "doc/assets",
-  logo: "./apps/xprof_gui/priv/build/xprof_icon.png",
-  source_url: "https://github.com/Appliscale/xprof",
-  homepage_url: "http://xprof.appliscale.io",
-]
diff --git a/doc/src/commands.md b/doc/src/commands.md
index ede35cc8..70990566 100644
--- a/doc/src/commands.md
+++ b/doc/src/commands.md
@@ -24,7 +24,7 @@ error
 ```
 
 ```elixir
-%funlatency retmatch: {:error, _},
+%Funlatency retmatch: {:error, _},
             mfa: Client.req/2
 ```
 
@@ -41,7 +41,7 @@ non-empty list.
 ```
 
 ```elixir
-%funlatency retmatch: fn({:ok, [_|_]}) -> false;
+%Funlatency retmatch: fn({:ok, [_|_]}) -> false;
                       (_)-> true end,
             mfa: Client.req(id, _) -> message(id)
 ```
@@ -58,7 +58,7 @@ but only captures the first element.
 ```
 
 ```elixir
-%funlatency retmatch: fn([h|_]) -> {true, h} end,
+%Funlatency retmatch: fn([h|_]) -> {true, h} end,
             mfa: Client.req/2
 ```
 
@@ -90,6 +90,6 @@ request map can take at runtime:
 ```
 
 ```elixir
-%argdist enum: 5,
+%Argdist enum: 5,
          mfa: Client.req(req) -> message(map_get(:cmp_id, req))
 ```
diff --git a/doc/src/querysyntax.md b/doc/src/querysyntax.md
index 2d33b4e0..80cc745e 100644
--- a/doc/src/querysyntax.md
+++ b/doc/src/querysyntax.md
@@ -26,7 +26,8 @@ give a function definition instead of arity. This gives the user the
 full power of match specifications and can be used both to selectively
 measure duration of function calls that match complicated filters and
 to capture only part of the arguments. The function has the same
-limitations as `dbg:fun2ms/1`. (See [Match Specifications in
+limitations as [`dbg:fun2ms/1`](https://www.erlang.org/doc/apps/runtime_tools/dbg.html#fun2ms/1).
+(See [Match Specifications in
 Erlang](http://erlang.org/doc/apps/erts/match_spec.html) and
 [ms\_transform](http://erlang.org/doc/man/ms_transform.html)).
 
@@ -113,7 +114,7 @@ simple query or an XProf-flavoured match-spec fun.
 The Erlang syntax is similar to a record,
 
 ```erlang
-#cmd param1: {"val", 1}, mfa: mod:fun(_)
+#cmd param1 = {"val", 1}, mfa = mod:fun(_)
 ```
 
 while the Elixir syntax is similar to a struct, both without the curly brackets.
diff --git a/rebar.config b/rebar.config
index 95d2adfe..153d3586 100644
--- a/rebar.config
+++ b/rebar.config
@@ -7,7 +7,7 @@
 
 {cover_excl_mods, [test_module]}.
 
-{shell, [{apps, [sync, xprof]}]}.
+{shell, [{apps, [xprof]}]}.
 
 {profiles,
  [{test,
@@ -25,10 +25,18 @@
    [{deps, [ {thoas, "0.4.0"} ]}
    ]},
   {dev,
-   [{deps, [ {sync, "0.1.3"} ]}
+   [ %% {deps, [ {sync, "0.1.3"} ]}
+   ]},
+  {docs,
+   %% rebar3_ex_doc is only needed to generate docs (make gen_ex_doc) and
+   %% does not compile on older OTP, so it is scoped to this profile rather
+   %% than declared as a global project plugin. Move back to project_plugins when
+   %% OTP 23 and below dropped.
+   [{minimum_otp_vsn, "24.0"}, %% edoc can generate doc chunks since OTP 24
+    {plugins, [rebar3_ex_doc]}
    ]},
   {publish,
-   [{plugins, [ {rebar3_hex, {git, "https://github.com/gomoripeti/rebar3_hex.git", {tag, "deps-3"}}} ]}
+   [{plugins, [ {rebar3_hex, {git, "https://github.com/gomoripeti/rebar3_hex.git", {tag, "deps-4"}}} ]}
    ]}
  ]}.
 
@@ -36,3 +44,17 @@
 {cover_export_enabled, true}.
 
 {coveralls_coverdata, [ "_build/test/cover/eunit.coverdata", "_build/test/cover/ct.coverdata" ]}.
+
+{ex_doc, [{main, "readme"},
+          {extras, ["doc/src/readme.md",
+                    {"doc/src/querysyntax.md", #{title => "Query Syntax"}},
+                    "doc/src/commands.md"
+                   ]},
+          {api_reference, false},
+          {assets, #{<<"doc/assets">> => <<"assets">>}},
+          {logo, "apps/xprof_gui/priv/build/xprof_icon.png"},
+          {proglang, erlang},
+          {source_url, "https://github.com/Appliscale/xprof"},
+          {homepage_url, "http://xprof.appliscale.io"},
+          {prefix_ref_vsn_with_v, false}
+         ]}.