diff --git a/src/heat_seek.rs b/src/heat_seek.rs
new file mode 100644
index 0000000..88cb54c
--- /dev/null
+++ b/src/heat_seek.rs
@@ -0,0 +1,153 @@
+use std::{collections::BTreeMap, num::NonZero};
+
+use tokio::sync::watch;
+use twilight_model::id::{
+    Id,
+    marker::{ChannelMarker, GuildMarker},
+};
+use twilight_util::builder::embed::EmbedBuilder;
+
+use crate::{OneToManyUniqueBTreeMap, State, call::join_and_record};
+
+type Heat = u64;
+type Hot = NonZero<Heat>;
+type HotOption = Option<Hot>;
+
+type ChannelHeat = BTreeMap<Id<ChannelMarker>, Heat>;
+type HeatMap = OneToManyUniqueBTreeMap<Heat, Id<ChannelMarker>>;
+
+#[tracing::instrument]
+async fn map_heat(
+    mut channel_heat_watcher: watch::Receiver<ChannelHeat>,
+    heat_map_sender: watch::Sender<HeatMap>,
+) {
+    loop {
+        heat_map_sender.send_modify(|heat_map| {
+            for (&channel, &heat) in &*channel_heat_watcher.borrow() {
+                heat_map.insert(heat, channel);
+            }
+        });
+
+        if let Err(_closed) = channel_heat_watcher.changed().await {
+            break;
+        }
+    }
+}
+
+#[tracing::instrument]
+async fn track_hottest_vc(
+    mut heat_map_watcher: watch::Receiver<HeatMap>,
+    hottest_vc_sender: watch::Sender<Option<Id<ChannelMarker>>>,
+) {
+    loop {
+        let new_hottest_vc_option = {
+            heat_map_watcher
+                .borrow()
+                .last_left_and_rights()
+                .and_then(|(&heat, hottest_vcs)| {
+                    let hot_option = Hot::new(heat);
+
+                    // TODO: tiebreak by whichever one this bot is already in
+                    hot_option.map(|_| *hottest_vcs.first().unwrap())
+                })
+        };
+
+        hottest_vc_sender.send_if_modified(|old_hottest_vc_option| {
+            let modified = (*old_hottest_vc_option) != new_hottest_vc_option;
+            *old_hottest_vc_option = new_hottest_vc_option;
+            modified
+        });
+
+        if let Err(_closed) = heat_map_watcher.changed().await {
+            break;
+        }
+    }
+}
+
+#[tracing::instrument]
+async fn follow_heat(
+    state: State,
+    guild_id: Id<GuildMarker>,
+    mut hottest_vc_watcher: watch::Receiver<Option<Id<ChannelMarker>>>,
+) {
+    loop {
+        let hottest_vc_option = { *hottest_vc_watcher.borrow() };
+
+        match hottest_vc_option {
+            Some(hottest_vc) => {
+                match join_and_record()
+                    .audio_channels(state.audio_channels)
+                    .audio_sample_rate(state.audio_sample_rate)
+                    .guild_id(guild_id)
+                    .recording_data(state.recording_data.clone())
+                    .songbird(&state.songbird)
+                    .user_data_manager(state.user_data_manager.clone())
+                    .voice_channel_id(hottest_vc)
+                    .call()
+                    .await
+                {
+                    Ok(()) => {
+                        let text_channel = state
+                            .discord_voice_channel_corresponding_text_channel
+                            .get(&guild_id)
+                            .and_then(|guild_mappings| {
+                                guild_mappings.get_left_for(&hottest_vc).copied()
+                            })
+                            .unwrap_or(hottest_vc);
+
+                        let vc_mention = format!("<#{hottest_vc}>");
+
+                        let info_mention = format!(
+                            "</{}:{}>",
+                            state.discord_info_command_name, state.discord_info_command_id
+                        );
+                        let opt_in_mention = format!(
+                            "</{}:{}>",
+                            state.discord_opt_in_command_name, state.discord_opt_in_command_id
+                        );
+                        let opt_out_mention = format!(
+                            "</{}:{}>",
+                            state.discord_opt_out_command_name, state.discord_opt_out_command_id
+                        );
+
+                        if let Err(posting_recording_disclosure_error) = state
+                            .discord_client
+                            .create_message(text_channel)
+                            .embeds(&[
+                                EmbedBuilder::new()
+                                    .title("Joined VC to record")
+                                    .description(format!("This bot joined {vc_mention} and intends to record. You can opt out with {opt_out_mention} or explicitly opt in with {opt_in_mention} (I'd appreciate this one). Please use {info_mention} for more information about this bot."))
+                                    .validate()
+                                    .unwrap()
+                                    .build()
+                            ])
+                            .await {
+                                tracing::error!(?text_channel, ?posting_recording_disclosure_error, "couldn't post a recording disclosure");
+                            }
+                    }
+                    Err(joining_to_record_error) => {
+                        tracing::error!(
+                            ?hottest_vc,
+                            ?joining_to_record_error,
+                            "couldn't join to record"
+                        );
+                    }
+                }
+            }
+            None => {
+                if let Err(leaving_error) = state.songbird.leave(guild_id).await {
+                    tracing::error!(?leaving_error, "couldn't leave vc");
+                }
+            }
+        }
+
+        if let Err(_closed) = hottest_vc_watcher.changed().await {
+            break;
+        }
+    }
+}
+
+#[tracing::instrument]
+pub async fn heat_seek(state: State) {
+    todo!();
+}
diff --git a/src/lib.rs b/src/lib.rs
index 58f84b2..ce8e1d3 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,6 +1,7 @@
 mod bot_data;
 mod call;
 pub mod command;
+mod heat_seek;
 mod one_to_many;
 mod one_to_many_with_data;
 mod one_to_one;