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diff --git a/src/purgatory/mod.rs b/src/purgatory/mod.rs
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+++ b/src/purgatory/mod.rs
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+//! Purgatory: In-memory holding area for events awaiting git data.
+//!
+//! Solves the "which arrives first?" problem where either nostr events or git pushes
+//! can arrive in any order. Events and git data are held temporarily until their
+//! counterpart arrives, at which point they can be processed together.
+//!
+//! ## Architecture
+//!
+//! - **In-memory only**: Data is lost on restart (acceptable per spec)
+//! - **Thread-safe**: Uses DashMap for concurrent access from multiple handlers
+//! - **Automatic expiry**: Entries expire after 30 minutes by default
+//! - **Separate stores**: State events and PR events use different indexing strategies
+
+mod helpers;
+mod types;
+
+pub use helpers::{can_satisfy_state, extract_refs_from_state, get_unpushed_refs};
+pub use types::{PrPurgatoryEntry, RefPair, RefUpdate, StatePurgatoryEntry};
+
+use dashmap::DashMap;
+use nostr_sdk::prelude::*;
+use std::sync::Arc;
+use std::time::{Duration, Instant};
+
+/// Default expiry duration for purgatory entries (30 minutes)
+const DEFAULT_EXPIRY: Duration = Duration::from_secs(1800);
+
+/// Main purgatory structure holding events awaiting git data.
+///
+/// Provides thread-safe concurrent access to two separate stores:
+/// - State events indexed by repository identifier
+/// - PR events indexed by event ID
+#[derive(Clone)]
+pub struct Purgatory {
+    /// State events (kind 30618) indexed by repository identifier.
+    /// Multiple state events can wait for the same identifier (different maintainers).
+    state_events: Arc<DashMap<String, Vec<StatePurgatoryEntry>>>,
+
+    /// PR events (kind 1617/1618) or placeholders indexed by event ID (hex string).
+    /// Event ID is from the 'e' tag in the PR event itself.
+    pr_events: Arc<DashMap<String, PrPurgatoryEntry>>,
+}
+
+impl Purgatory {
+    /// Create a new empty purgatory.
+    pub fn new() -> Self {
+        Self {
+            state_events: Arc::new(DashMap::new()),
+            pr_events: Arc::new(DashMap::new()),
+        }
+    }
+
+    /// Add a state event to purgatory.
+    ///
+    /// The event will expire after the default duration unless matched with git data.
+    /// Multiple state events for the same identifier are allowed (from different authors).
+    ///
+    /// # Arguments
+    /// * `event` - The state event (kind 30618) to hold
+    /// * `identifier` - The repository identifier from the 'd' tag
+    /// * `author` - The event author's public key
+    pub fn add_state(&self, event: Event, identifier: String, author: PublicKey) {
+        let now = Instant::now();
+        let entry = StatePurgatoryEntry {
+            event,
+            identifier: identifier.clone(),
+            author,
+            created_at: now,
+            expires_at: now + DEFAULT_EXPIRY,
+        };
+
+        self.state_events.entry(identifier).or_default().push(entry);
+    }
+
+    /// Add a PR event to purgatory.
+    ///
+    /// The event will expire after the default duration unless matched with git data.
+    ///
+    /// # Arguments
+    /// * `event` - The PR event (kind 1617/1618) to hold
+    /// * `event_id` - The event ID (hex string) from the 'e' tag
+    /// * `commit` - The commit SHA from the 'c' tag
+    pub fn add_pr(&self, event: Event, event_id: String, commit: String) {
+        let now = Instant::now();
+        let entry = PrPurgatoryEntry {
+            event: Some(event),
+            commit,
+            created_at: now,
+            expires_at: now + DEFAULT_EXPIRY,
+        };
+
+        self.pr_events.insert(event_id, entry);
+    }
+
+    /// Add a PR placeholder (git data arrived before PR event).
+    ///
+    /// Creates a placeholder entry waiting for the corresponding PR event.
+    ///
+    /// # Arguments
+    /// * `event_id` - The expected event ID (from git ref name)
+    /// * `commit` - The commit SHA that was pushed
+    pub fn add_pr_placeholder(&self, event_id: String, commit: String) {
+        let now = Instant::now();
+        let entry = PrPurgatoryEntry {
+            event: None, // Placeholder - no event yet
+            commit,
+            created_at: now,
+            expires_at: now + DEFAULT_EXPIRY,
+        };
+
+        self.pr_events.insert(event_id, entry);
+    }
+
+    /// Find state events waiting for a specific repository identifier.
+    ///
+    /// Returns all state events (from all maintainers) waiting for git data
+    /// matching this identifier.
+    ///
+    /// # Arguments
+    /// * `identifier` - The repository identifier to search for
+    ///
+    /// # Returns
+    /// Vector of state events waiting for this identifier, or empty vec if none found
+    pub fn find_state(&self, identifier: &str) -> Vec<StatePurgatoryEntry> {
+        self.state_events
+            .get(identifier)
+            .map(|entries| entries.clone())
+            .unwrap_or_default()
+    }
+
+    /// Find a PR event or placeholder by event ID.
+    ///
+    /// # Arguments
+    /// * `event_id` - The event ID to search for
+    ///
+    /// # Returns
+    /// The PR entry if found, None otherwise
+    pub fn find_pr(&self, event_id: &str) -> Option<PrPurgatoryEntry> {
+        self.pr_events.get(event_id).map(|entry| entry.clone())
+    }
+
+    /// Find a PR placeholder specifically (git-data-first scenario).
+    ///
+    /// Returns the commit SHA only if a placeholder exists (entry with no event).
+    /// Used to distinguish placeholders from actual PR events.
+    ///
+    /// # Arguments
+    /// * `event_id` - The event ID to search for
+    ///
+    /// # Returns
+    /// Some(commit_sha) if a placeholder exists, None if no entry or entry has an event
+    pub fn find_pr_placeholder(&self, event_id: &str) -> Option<String> {
+        self.pr_events.get(event_id).and_then(|entry| {
+            if entry.event.is_none() {
+                Some(entry.commit.clone())
+            } else {
+                None
+            }
+        })
+    }
+
+    /// Remove a state event from purgatory.
+    ///
+    /// Removes all entries for the given identifier.
+    ///
+    /// # Arguments
+    /// * `identifier` - The repository identifier to remove
+    pub fn remove_state(&self, identifier: &str) {
+        self.state_events.remove(identifier);
+    }
+
+    /// Remove a specific state event by comparing the full event.
+    ///
+    /// This allows removing a single state event while leaving others
+    /// for the same identifier intact.
+    ///
+    /// # Arguments
+    /// * `identifier` - The repository identifier
+    /// * `event_id` - The specific event ID to remove
+    pub fn remove_state_event(&self, identifier: &str, event_id: &EventId) {
+        if let Some(mut entries) = self.state_events.get_mut(identifier) {
+            entries.retain(|entry| entry.event.id != *event_id);
+            if entries.is_empty() {
+                drop(entries); // Release lock before removal
+                self.state_events.remove(identifier);
+            }
+        }
+    }
+
+    /// Find state events that could be satisfied by ref updates.
+    ///
+    /// Returns state events waiting for this identifier where applying the
+    /// ref updates to local state results in exactly the declared state.
+    /// Uses late-binding ref extraction at git push time.
+    ///
+    /// # Arguments
+    /// * `identifier` - The repository identifier to search for
+    /// * `pushed_updates` - Ref updates in the current push operation
+    /// * `local_refs` - Refs already existing locally (ref_name -> SHA)
+    ///
+    /// # Returns
+    /// Vector of events that can be satisfied by the push
+    pub fn find_matching_states(
+        &self,
+        identifier: &str,
+        pushed_updates: &[RefUpdate],
+        local_refs: &std::collections::HashMap<String, String>,
+    ) -> Vec<Event> {
+        self.state_events
+            .get(identifier)
+            .map(|entries| {
+                entries
+                    .iter()
+                    .filter(|entry| {
+                        helpers::can_satisfy_state(&entry.event, pushed_updates, local_refs)
+                    })
+                    .map(|entry| entry.event.clone())
+                    .collect()
+            })
+            .unwrap_or_default()
+    }
+
+    /// Extend expiry for state events about to be processed.
+    ///
+    /// Ensures entries have at least `duration` remaining on their timer.
+    /// Sets expiry to max(current_expiry, now + duration).
+    ///
+    /// # Arguments
+    /// * `identifier` - The repository identifier
+    /// * `event_ids` - Event IDs to extend expiry for
+    /// * `duration` - Minimum duration to guarantee from now
+    pub fn extend_expiry(&self, identifier: &str, event_ids: &[EventId], duration: Duration) {
+        if let Some(mut entries) = self.state_events.get_mut(identifier) {
+            let now = Instant::now();
+            let new_expiry = now + duration;
+
+            for entry in entries.iter_mut() {
+                if event_ids.contains(&entry.event.id) {
+                    // Set to max of current expiry and new expiry
+                    if entry.expires_at < new_expiry {
+                        entry.expires_at = new_expiry;
+                    }
+                }
+            }
+        }
+    }
+
+    /// Remove a PR event or placeholder from purgatory.
+    ///
+    /// # Arguments
+    /// * `event_id` - The event ID to remove
+    pub fn remove_pr(&self, event_id: &str) {
+        self.pr_events.remove(event_id);
+    }
+
+    /// Get all PR placeholder event IDs (git-data-first entries without events).
+    ///
+    /// Returns event IDs for entries where git data arrived before the PR event.
+    /// These correspond to `refs/nostr/<event-id>` refs that should be cleaned up
+    /// on shutdown since they don't have corresponding events.
+    ///
+    /// # Returns
+    /// Vector of event IDs (hex strings) for placeholder entries
+    pub fn get_placeholder_event_ids(&self) -> Vec<String> {
+        self.pr_events
+            .iter()
+            .filter_map(|entry| {
+                if entry.value().event.is_none() {
+                    Some(entry.key().clone())
+                } else {
+                    None
+                }
+            })
+            .collect()
+    }
+
+    /// Remove expired entries from purgatory.
+    ///
+    /// Should be called periodically (every 60 seconds) by background task to clean up
+    /// entries that have exceeded their expiry deadline.
+    ///
+    /// # Returns
+    /// Tuple of (num_state_removed, num_pr_removed)
+    pub fn cleanup(&self) -> (usize, usize) {
+        let now = Instant::now();
+        let mut state_removed = 0;
+
+        // Remove expired state events
+        self.state_events.retain(|_, entries| {
+            let original_len = entries.len();
+            entries.retain(|entry| entry.expires_at > now);
+            state_removed += original_len - entries.len();
+            !entries.is_empty()
+        });
+
+        // Remove expired PR events
+        let expired_prs: Vec<String> = self
+            .pr_events
+            .iter()
+            .filter(|entry| entry.value().expires_at <= now)
+            .map(|entry| entry.key().clone())
+            .collect();
+
+        let pr_removed = expired_prs.len();
+        for event_id in expired_prs {
+            self.pr_events.remove(&event_id);
+        }
+
+        (state_removed, pr_removed)
+    }
+
+    /// Remove expired entries from purgatory (legacy method).
+    ///
+    /// # Returns
+    /// Total number of entries removed (state + PR events)
+    #[deprecated(since = "0.1.0", note = "Use cleanup() instead for separate counts")]
+    pub fn remove_expired(&self) -> usize {
+        let (state, pr) = self.cleanup();
+        state + pr
+    }
+
+    /// Get current count of entries in purgatory.
+    ///
+    /// # Returns
+    /// Tuple of (state_event_count, pr_event_count)
+    pub fn count(&self) -> (usize, usize) {
+        let state_count: usize = self.state_events.iter().map(|e| e.value().len()).sum();
+        let pr_count = self.pr_events.len();
+        (state_count, pr_count)
+    }
+
+    /// Clear all entries from purgatory (for testing).
+    #[cfg(test)]
+    pub fn clear(&self) {
+        self.state_events.clear();
+        self.pr_events.clear();
+    }
+}
+
+impl Default for Purgatory {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_purgatory_creation() {
+        let purgatory = Purgatory::new();
+        let (state_count, pr_count) = purgatory.count();
+        assert_eq!(state_count, 0);
+        assert_eq!(pr_count, 0);
+    }
+
+    #[test]
+    fn test_purgatory_count() {
+        let purgatory = Purgatory::new();
+
+        // Add some test data
+        let keys = Keys::generate();
+        let event = EventBuilder::text_note("test")
+            .sign_with_keys(&keys)
+            .unwrap();
+
+        purgatory.add_state(event.clone(), "test-repo".to_string(), keys.public_key());
+        purgatory.add_pr(event, "test-event-id".to_string(), "abc123".to_string());
+
+        let (state_count, pr_count) = purgatory.count();
+        assert_eq!(state_count, 1);
+        assert_eq!(pr_count, 1);
+    }
+}
+
+#[test]
+fn test_pr_event_vs_placeholder() {
+    let purgatory = Purgatory::new();
+    let keys = Keys::generate();
+    let event = EventBuilder::text_note("test PR")
+        .sign_with_keys(&keys)
+        .unwrap();
+
+    // Add a PR event with actual event
+    purgatory.add_pr(
+        event.clone(),
+        "event-id-1".to_string(),
+        "commit-abc".to_string(),
+    );
+
+    // Add a placeholder (no event)
+    purgatory.add_pr_placeholder("event-id-2".to_string(), "commit-def".to_string());
+
+    // find_pr should find both
+    assert!(purgatory.find_pr("event-id-1").is_some());
+    assert!(purgatory.find_pr("event-id-2").is_some());
+
+    // find_pr_placeholder should only find the placeholder
+    assert!(purgatory.find_pr_placeholder("event-id-1").is_none());
+    assert_eq!(
+        purgatory.find_pr_placeholder("event-id-2"),
+        Some("commit-def".to_string())
+    );
+}
+
+#[test]
+fn test_pr_placeholder_creation_and_retrieval() {
+    let purgatory = Purgatory::new();
+
+    // Add a placeholder
+    purgatory.add_pr_placeholder("placeholder-id".to_string(), "commit-123".to_string());
+
+    // Should be findable by find_pr
+    let entry = purgatory.find_pr("placeholder-id");
+    assert!(entry.is_some());
+    let entry = entry.unwrap();
+    assert!(entry.event.is_none()); // No event yet
+    assert_eq!(entry.commit, "commit-123");
+
+    // Should be findable by find_pr_placeholder
+    let commit = purgatory.find_pr_placeholder("placeholder-id");
+    assert_eq!(commit, Some("commit-123".to_string()));
+}
+
+#[test]
+fn test_cleanup_removes_expired_entries() {
+    use std::time::Duration;
+
+    let purgatory = Purgatory::new();
+    let keys = Keys::generate();
+
+    // Create events
+    let state_event = EventBuilder::text_note("state event")
+        .sign_with_keys(&keys)
+        .unwrap();
+    let pr_event = EventBuilder::text_note("pr event")
+        .sign_with_keys(&keys)
+        .unwrap();
+
+    // Add entries to purgatory
+    purgatory.add_state(
+        state_event.clone(),
+        "test-repo".to_string(),
+        keys.public_key(),
+    );
+    purgatory.add_pr(pr_event, "pr-123".to_string(), "commit-abc".to_string());
+    purgatory.add_pr_placeholder("pr-456".to_string(), "commit-def".to_string());
+
+    // Verify entries are there
+    let (state_count, pr_count) = purgatory.count();
+    assert_eq!(state_count, 1);
+    assert_eq!(pr_count, 2);
+
+    // Manually expire entries by modifying their expiry time
+    // (This is a bit hacky but needed for testing without waiting 30 minutes)
+    if let Some(mut entries) = purgatory.state_events.get_mut("test-repo") {
+        for entry in entries.iter_mut() {
+            entry.expires_at = Instant::now() - Duration::from_secs(1);
+        }
+    }
+
+    // Expire PR events
+    for mut entry in purgatory.pr_events.iter_mut() {
+        entry.value_mut().expires_at = Instant::now() - Duration::from_secs(1);
+    }
+
+    // Run cleanup
+    let (state_removed, pr_removed) = purgatory.cleanup();
+
+    // Verify counts
+    assert_eq!(state_removed, 1);
+    assert_eq!(pr_removed, 2);
+
+    // Verify entries are gone
+    let (state_count, pr_count) = purgatory.count();
+    assert_eq!(state_count, 0);
+    assert_eq!(pr_count, 0);
+}
+
+#[test]
+fn test_cleanup_preserves_non_expired_entries() {
+    let purgatory = Purgatory::new();
+    let keys = Keys::generate();
+
+    let state_event = EventBuilder::text_note("state event")
+        .sign_with_keys(&keys)
+        .unwrap();
+    let pr_event = EventBuilder::text_note("pr event")
+        .sign_with_keys(&keys)
+        .unwrap();
+
+    // Add fresh entries
+    purgatory.add_state(state_event, "test-repo".to_string(), keys.public_key());
+    purgatory.add_pr(pr_event, "pr-123".to_string(), "commit-abc".to_string());
+
+    // Run cleanup
+    let (state_removed, pr_removed) = purgatory.cleanup();
+
+    // Nothing should be removed
+    assert_eq!(state_removed, 0);
+    assert_eq!(pr_removed, 0);
+
+    // Verify entries are still there
+    let (state_count, pr_count) = purgatory.count();
+    assert_eq!(state_count, 1);
+    assert_eq!(pr_count, 1);
+}
+
+#[test]
+fn test_cleanup_mixed_expired_and_fresh() {
+    use std::time::Duration;
+
+    let purgatory = Purgatory::new();
+    let keys = Keys::generate();
+
+    // Add multiple state events for same repo
+    let event1 = EventBuilder::text_note("event1")
+        .sign_with_keys(&keys)
+        .unwrap();
+    let event2 = EventBuilder::text_note("event2")
+        .sign_with_keys(&keys)
+        .unwrap();
+
+    purgatory.add_state(event1, "test-repo".to_string(), keys.public_key());
+    purgatory.add_state(event2, "test-repo".to_string(), keys.public_key());
+
+    // Expire only the first one
+    if let Some(mut entries) = purgatory.state_events.get_mut("test-repo") {
+        if let Some(entry) = entries.get_mut(0) {
+            entry.expires_at = Instant::now() - Duration::from_secs(1);
+        }
+    }
+
+    // Add PR events
+    let pr1 = EventBuilder::text_note("pr1")
+        .sign_with_keys(&keys)
+        .unwrap();
+    let pr2 = EventBuilder::text_note("pr2")
+        .sign_with_keys(&keys)
+        .unwrap();
+
+    purgatory.add_pr(pr1, "pr-1".to_string(), "commit-1".to_string());
+    purgatory.add_pr(pr2, "pr-2".to_string(), "commit-2".to_string());
+
+    // Expire only first PR
+    if let Some(mut entry) = purgatory.pr_events.get_mut("pr-1") {
+        entry.expires_at = Instant::now() - Duration::from_secs(1);
+    }
+
+    // Run cleanup
+    let (state_removed, pr_removed) = purgatory.cleanup();
+
+    // One of each should be removed
+    assert_eq!(state_removed, 1);
+    assert_eq!(pr_removed, 1);
+
+    // Verify remaining counts
+    let (state_count, pr_count) = purgatory.count();
+    assert_eq!(state_count, 1); // One state event remains
+    assert_eq!(pr_count, 1); // One PR event remains
+}
+
+#[test]
+fn test_remove_expired_legacy_method() {
+    use std::time::Duration;
+
+    let purgatory = Purgatory::new();
+    let keys = Keys::generate();
+
+    let state_event = EventBuilder::text_note("state")
+        .sign_with_keys(&keys)
+        .unwrap();
+    let pr_event = EventBuilder::text_note("pr").sign_with_keys(&keys).unwrap();
+
+    purgatory.add_state(state_event, "repo".to_string(), keys.public_key());
+    purgatory.add_pr(pr_event, "pr-id".to_string(), "commit".to_string());
+
+    // Expire both
+    if let Some(mut entries) = purgatory.state_events.get_mut("repo") {
+        for entry in entries.iter_mut() {
+            entry.expires_at = Instant::now() - Duration::from_secs(1);
+        }
+    }
+    for mut entry in purgatory.pr_events.iter_mut() {
+        entry.value_mut().expires_at = Instant::now() - Duration::from_secs(1);
+    }
+
+    // Test legacy method returns total
+    #[allow(deprecated)]
+    let total = purgatory.remove_expired();
+    assert_eq!(total, 2); // 1 state + 1 PR
+}