v0.2.4 - Clean up config issues

.gitignore

@@ -1,3 +1,5 @@
 nostr_core_lib/
 nips/
 build/
+relay.log
+Trash/

.roo/rules-code/rules.md

@@ -0,0 +1 @@
+Use ./make_and_restart_relay.sh instead of make to build the project. 

Makefile

@@ -9,7 +9,7 @@ LIBS = -lsqlite3 -lwebsockets -lz -ldl -lpthread -lm -L/usr/local/lib -lsecp256k
 BUILD_DIR = build
 
 # Source files
-MAIN_SRC = src/main.c
+MAIN_SRC = src/main.c src/config.c
 NOSTR_CORE_LIB = nostr_core_lib/libnostr_core_x64.a
 
 # Architecture detection

README.md

@@ -14,76 +14,9 @@ Do NOT modify the formatting, add emojis, or change the text. Keep the simple fo
 - [x] NIP-13: Proof of Work
 - [x] NIP-15: End of Stored Events Notice
 - [x] NIP-20: Command Results
-- [ ] NIP-22: Event `created_at` Limits
-- [ ] NIP-25: Reactions
-- [ ] NIP-26: Delegated Event Signing
-- [ ] NIP-28: Public Chat
-- [ ] NIP-33: Parameterized Replaceable Events
-- [ ] NIP-40: Expiration Timestamp
+- [x] NIP-33: Parameterized Replaceable Events
+- [x] NIP-40: Expiration Timestamp
 - [ ] NIP-42: Authentication of clients to relays
-- [ ] NIP-45: Counting results. [experimental](#count)
-- [ ] NIP-50: Keywords filter. [experimental](#search)
+- [ ] NIP-45: Counting results.
+- [ ] NIP-50: Keywords filter.
 - [ ] NIP-70: Protected Events
-
-## NIP-13: Proof of Work Configuration
-
-The relay supports NIP-13 Proof of Work validation with configurable settings. PoW validation helps prevent spam and ensures computational commitment from event publishers.
-
-### Environment Variables
-
-Configure PoW validation using these environment variables:
-
-- `RELAY_POW_ENABLED` - Enable/disable PoW validation (default: `1`)
-  - `1`, `true`, or `yes` to enable
-  - `0`, `false`, or `no` to disable
-
-- `RELAY_MIN_POW_DIFFICULTY` - Minimum required difficulty (default: `0`)
-  - Range: `0-64` (reasonable bounds)
-  - `0` = no minimum requirement (events without PoW are accepted)
-  - Higher values require more computational work
-
-- `RELAY_POW_MODE` - Validation mode (default: `basic`)
-  - `basic` - Basic PoW validation
-  - `full` - Full validation with nonce tag requirements
-  - `strict` - Strict anti-spam mode with committed target validation
-  - `disabled` - Disable PoW validation entirely
-
-### Examples
-
-```bash
-# Basic setup - accept events with or without PoW
-export RELAY_POW_ENABLED=1
-export RELAY_MIN_POW_DIFFICULTY=0
-export RELAY_POW_MODE=basic
-
-# Anti-spam setup - require minimum difficulty 16
-export RELAY_POW_ENABLED=1
-export RELAY_MIN_POW_DIFFICULTY=16
-export RELAY_POW_MODE=strict
-
-# Disable PoW validation completely
-export RELAY_POW_ENABLED=0
-```
-
-### Behavior
-
-- **min_difficulty=0**: Events without PoW are accepted; events with PoW are validated
-- **min_difficulty>0**: All events must have valid PoW meeting minimum difficulty
-- **strict mode**: Additional validation prevents difficulty commitment gaming
-- **NIP-11 integration**: PoW configuration is advertised via relay information document
-
-### Testing
-
-Run the comprehensive PoW test suite:
-
-```bash
-./tests/13_nip_test.sh
-```
-
-The test suite validates:
-- NIP-11 PoW support advertisement
-- Event acceptance without PoW (when min_difficulty=0)
-- Event validation with valid PoW
-- Configuration via environment variables
-- NIP-13 reference event validation
-

build_output.log

@@ -0,0 +1,28 @@
+=== C Nostr Relay Build and Restart Script ===
+Removing old configuration file to trigger regeneration...
+✓ Configuration file removed - will be regenerated with latest database values
+Building project...
+rm -rf build
+Clean complete
+mkdir -p build
+Compiling C-Relay for architecture: x86_64
+gcc -Wall -Wextra -std=c99 -g -O2 -I. -Inostr_core_lib -Inostr_core_lib/nostr_core -Inostr_core_lib/cjson -Inostr_core_lib/nostr_websocket src/main.c src/config.c -o build/c_relay_x86 nostr_core_lib/libnostr_core_x64.a -lsqlite3 -lwebsockets -lz -ldl -lpthread -lm -L/usr/local/lib -lsecp256k1 -lssl -lcrypto -L/usr/local/lib -lcurl
+Build complete: build/c_relay_x86
+Build successful. Proceeding with relay restart...
+Stopping any existing relay servers...
+No existing relay found
+Starting relay server...
+Debug: Current processes: None
+Started with PID: 786684
+Relay started successfully!
+PID: 786684
+WebSocket endpoint: ws://127.0.0.1:8888
+Log file: relay.log
+
+=== Relay server running in background ===
+To kill relay: pkill -f 'c_relay_'
+To check status: ps aux | grep c_relay_
+To view logs: tail -f relay.log
+Binary: ./build/c_relay_x86
+Ready for Nostr client connections!
+

db/init.sh

@@ -114,12 +114,12 @@ verify_database() {
     local schema_version=$(sqlite3 "$DB_PATH" "PRAGMA user_version;")
     log_info "Database schema version: $schema_version"
     
-    # Check that main tables exist
-    local table_count=$(sqlite3 "$DB_PATH" "SELECT count(*) FROM sqlite_master WHERE type='table' AND name IN ('events', 'schema_info');")
-    if [ "$table_count" -eq 2 ]; then
-        log_success "Core tables created successfully"
+    # Check that main tables exist (including configuration tables)
+    local table_count=$(sqlite3 "$DB_PATH" "SELECT count(*) FROM sqlite_master WHERE type='table' AND name IN ('events', 'schema_info', 'server_config');")
+    if [ "$table_count" -eq 3 ]; then
+        log_success "Core tables created successfully (including configuration tables)"
     else
-        log_error "Missing core tables (expected 2, found $table_count)"
+        log_error "Missing core tables (expected 3, found $table_count)"
         exit 1
     fi
 }

db/schema.sql

@@ -2,7 +2,7 @@
 -- SQLite schema for storing Nostr events with JSON tags support
 
 -- Schema version tracking
-PRAGMA user_version = 2;
+PRAGMA user_version = 3;
 
 -- Enable foreign key support
 PRAGMA foreign_keys = ON;
@@ -44,9 +44,9 @@ CREATE TABLE schema_info (
 );
 
 -- Insert schema metadata
-INSERT INTO schema_info (key, value) VALUES 
-    ('version', '2'),
-    ('description', 'Hybrid single-table Nostr relay schema with JSON tags'),
+INSERT INTO schema_info (key, value) VALUES
+    ('version', '3'),
+    ('description', 'Hybrid single-table Nostr relay schema with JSON tags and configuration management'),
     ('created_at', strftime('%s', 'now'));
 
 -- Helper views for common queries
@@ -178,4 +178,122 @@ WHERE event_type = 'created'
 AND subscription_id NOT IN (
     SELECT subscription_id FROM subscription_events
     WHERE event_type IN ('closed', 'expired', 'disconnected')
-);
+);
+
+-- ================================
+-- CONFIGURATION MANAGEMENT TABLES
+-- ================================
+
+-- Core server configuration table
+CREATE TABLE server_config (
+    key TEXT PRIMARY KEY,                    -- Configuration key (unique identifier)
+    value TEXT NOT NULL,                     -- Configuration value (stored as string)
+    description TEXT,                        -- Human-readable description
+    config_type TEXT DEFAULT 'user' CHECK (config_type IN ('system', 'user', 'runtime')),
+    data_type TEXT DEFAULT 'string' CHECK (data_type IN ('string', 'integer', 'boolean', 'json')),
+    validation_rules TEXT,                   -- JSON validation rules (optional)
+    is_sensitive INTEGER DEFAULT 0,          -- 1 if value should be masked in logs
+    requires_restart INTEGER DEFAULT 0,      -- 1 if change requires server restart
+    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
+    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
+);
+
+-- Configuration change history table
+CREATE TABLE config_history (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    config_key TEXT NOT NULL,               -- Key that was changed
+    old_value TEXT,                         -- Previous value (NULL for new keys)
+    new_value TEXT NOT NULL,                -- New value
+    changed_by TEXT DEFAULT 'system',       -- Who made the change (system/admin/user)
+    change_reason TEXT,                     -- Optional reason for change
+    changed_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
+    FOREIGN KEY (config_key) REFERENCES server_config(key)
+);
+
+-- Configuration validation errors log
+CREATE TABLE config_validation_log (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    config_key TEXT NOT NULL,
+    attempted_value TEXT,
+    validation_error TEXT NOT NULL,
+    error_source TEXT DEFAULT 'validation',  -- validation/parsing/constraint
+    attempted_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
+);
+
+-- Cache for file-based configuration events
+CREATE TABLE config_file_cache (
+    file_path TEXT PRIMARY KEY,             -- Full path to config file
+    file_hash TEXT NOT NULL,                -- SHA256 hash of file content
+    event_id TEXT,                          -- Nostr event ID from file
+    event_pubkey TEXT,                      -- Admin pubkey that signed event
+    loaded_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
+    validation_status TEXT CHECK (validation_status IN ('valid', 'invalid', 'unverified')),
+    validation_error TEXT                   -- Error details if invalid
+);
+
+-- Performance indexes for configuration tables
+CREATE INDEX idx_server_config_type ON server_config(config_type);
+CREATE INDEX idx_server_config_updated ON server_config(updated_at DESC);
+CREATE INDEX idx_config_history_key ON config_history(config_key);
+CREATE INDEX idx_config_history_time ON config_history(changed_at DESC);
+CREATE INDEX idx_config_validation_key ON config_validation_log(config_key);
+CREATE INDEX idx_config_validation_time ON config_validation_log(attempted_at DESC);
+
+-- Trigger to update timestamp on configuration changes
+CREATE TRIGGER update_config_timestamp
+    AFTER UPDATE ON server_config
+BEGIN
+    UPDATE server_config SET updated_at = strftime('%s', 'now') WHERE key = NEW.key;
+END;
+
+-- Trigger to log configuration changes to history
+CREATE TRIGGER log_config_changes
+    AFTER UPDATE ON server_config
+    WHEN OLD.value != NEW.value
+BEGIN
+    INSERT INTO config_history (config_key, old_value, new_value, changed_by, change_reason)
+    VALUES (NEW.key, OLD.value, NEW.value, 'system', 'configuration update');
+END;
+
+-- Active Configuration View
+CREATE VIEW active_config AS
+SELECT
+    key,
+    value,
+    description,
+    config_type,
+    data_type,
+    requires_restart,
+    updated_at
+FROM server_config
+WHERE config_type IN ('system', 'user')
+ORDER BY config_type, key;
+
+-- Runtime Statistics View
+CREATE VIEW runtime_stats AS
+SELECT
+    key,
+    value,
+    description,
+    updated_at
+FROM server_config
+WHERE config_type = 'runtime'
+ORDER BY key;
+
+-- Configuration Change Summary
+CREATE VIEW recent_config_changes AS
+SELECT
+    ch.config_key,
+    sc.description,
+    ch.old_value,
+    ch.new_value,
+    ch.changed_by,
+    ch.change_reason,
+    ch.changed_at
+FROM config_history ch
+JOIN server_config sc ON ch.config_key = sc.key
+ORDER BY ch.changed_at DESC
+LIMIT 50;
+
+-- Runtime Statistics (initialized by server on startup)
+-- These will be populated when configuration system initializes

docs/config_schema_design.md

@@ -0,0 +1,280 @@
+# Database Configuration Schema Design
+
+## Overview
+This document outlines the database configuration schema additions for the C Nostr Relay startup config file system. The design follows the Ginxsom admin system approach with signed Nostr events and database storage.
+
+## Schema Version Update
+- Current Version: 2
+- Target Version: 3
+- Update: Add server configuration management tables
+
+## Core Configuration Tables
+
+### 1. `server_config` Table
+
+```sql
+-- Server configuration table - core configuration storage
+CREATE TABLE server_config (
+    key TEXT PRIMARY KEY,                    -- Configuration key (unique identifier)
+    value TEXT NOT NULL,                     -- Configuration value (stored as string)
+    description TEXT,                        -- Human-readable description
+    config_type TEXT DEFAULT 'user' CHECK (config_type IN ('system', 'user', 'runtime')),
+    data_type TEXT DEFAULT 'string' CHECK (data_type IN ('string', 'integer', 'boolean', 'json')),
+    validation_rules TEXT,                   -- JSON validation rules (optional)
+    is_sensitive INTEGER DEFAULT 0,          -- 1 if value should be masked in logs
+    requires_restart INTEGER DEFAULT 0,      -- 1 if change requires server restart
+    created_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
+    updated_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
+);
+```
+
+**Configuration Types:**
+- `system`: Core system settings (admin keys, security)
+- `user`: User-configurable settings (relay info, features)
+- `runtime`: Dynamic runtime values (statistics, cache)
+
+**Data Types:**
+- `string`: Text values
+- `integer`: Numeric values
+- `boolean`: True/false values (stored as "true"/"false")
+- `json`: JSON object/array values
+
+### 2. `config_history` Table
+
+```sql
+-- Configuration change history table
+CREATE TABLE config_history (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    config_key TEXT NOT NULL,               -- Key that was changed
+    old_value TEXT,                         -- Previous value (NULL for new keys)
+    new_value TEXT NOT NULL,                -- New value
+    changed_by TEXT DEFAULT 'system',       -- Who made the change (system/admin/user)
+    change_reason TEXT,                     -- Optional reason for change
+    changed_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
+    FOREIGN KEY (config_key) REFERENCES server_config(key)
+);
+```
+
+### 3. `config_validation_log` Table
+
+```sql
+-- Configuration validation errors log
+CREATE TABLE config_validation_log (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    config_key TEXT NOT NULL,
+    attempted_value TEXT,
+    validation_error TEXT NOT NULL,
+    error_source TEXT DEFAULT 'validation',  -- validation/parsing/constraint
+    attempted_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now'))
+);
+```
+
+### 4. Configuration File Cache Table
+
+```sql
+-- Cache for file-based configuration events
+CREATE TABLE config_file_cache (
+    file_path TEXT PRIMARY KEY,             -- Full path to config file
+    file_hash TEXT NOT NULL,                -- SHA256 hash of file content
+    event_id TEXT,                          -- Nostr event ID from file
+    event_pubkey TEXT,                      -- Admin pubkey that signed event
+    loaded_at INTEGER NOT NULL DEFAULT (strftime('%s', 'now')),
+    validation_status TEXT CHECK (validation_status IN ('valid', 'invalid', 'unverified')),
+    validation_error TEXT                   -- Error details if invalid
+);
+```
+
+## Indexes and Performance
+
+```sql
+-- Performance indexes for configuration tables
+CREATE INDEX idx_server_config_type ON server_config(config_type);
+CREATE INDEX idx_server_config_updated ON server_config(updated_at DESC);
+CREATE INDEX idx_config_history_key ON config_history(config_key);
+CREATE INDEX idx_config_history_time ON config_history(changed_at DESC);
+CREATE INDEX idx_config_validation_key ON config_validation_log(config_key);
+CREATE INDEX idx_config_validation_time ON config_validation_log(attempted_at DESC);
+```
+
+## Triggers
+
+### Update Timestamp Trigger
+
+```sql
+-- Trigger to update timestamp on configuration changes
+CREATE TRIGGER update_config_timestamp
+    AFTER UPDATE ON server_config
+BEGIN
+    UPDATE server_config SET updated_at = strftime('%s', 'now') WHERE key = NEW.key;
+END;
+```
+
+### Configuration History Trigger
+
+```sql
+-- Trigger to log configuration changes to history
+CREATE TRIGGER log_config_changes
+    AFTER UPDATE ON server_config
+    WHEN OLD.value != NEW.value
+BEGIN
+    INSERT INTO config_history (config_key, old_value, new_value, changed_by, change_reason)
+    VALUES (NEW.key, OLD.value, NEW.value, 'system', 'configuration update');
+END;
+```
+
+## Default Configuration Values
+
+### Core System Settings
+
+```sql
+INSERT OR IGNORE INTO server_config (key, value, description, config_type, data_type, requires_restart) VALUES
+-- Administrative settings
+('admin_pubkey', '', 'Authorized admin public key (hex)', 'system', 'string', 1),
+('admin_enabled', 'false', 'Enable admin interface', 'system', 'boolean', 1),
+
+-- Server core settings
+('relay_port', '8888', 'WebSocket server port', 'user', 'integer', 1),
+('database_path', 'db/c_nostr_relay.db', 'SQLite database file path', 'user', 'string', 1),
+('max_connections', '100', 'Maximum concurrent connections', 'user', 'integer', 1),
+
+-- NIP-11 Relay Information
+('relay_name', 'C Nostr Relay', 'Relay name for NIP-11', 'user', 'string', 0),
+('relay_description', 'High-performance C Nostr relay with SQLite storage', 'Relay description', 'user', 'string', 0),
+('relay_contact', '', 'Contact information', 'user', 'string', 0),
+('relay_pubkey', '', 'Relay public key', 'user', 'string', 0),
+('relay_software', 'https://git.laantungir.net/laantungir/c-relay.git', 'Software URL', 'user', 'string', 0),
+('relay_version', '0.2.0', 'Software version', 'user', 'string', 0),
+
+-- NIP-13 Proof of Work
+('pow_enabled', 'true', 'Enable NIP-13 Proof of Work validation', 'user', 'boolean', 0),
+('pow_min_difficulty', '0', 'Minimum PoW difficulty required', 'user', 'integer', 0),
+('pow_mode', 'basic', 'PoW validation mode (basic/full/strict)', 'user', 'string', 0),
+
+-- NIP-40 Expiration Timestamp
+('expiration_enabled', 'true', 'Enable NIP-40 expiration handling', 'user', 'boolean', 0),
+('expiration_strict', 'true', 'Reject expired events on submission', 'user', 'boolean', 0),
+('expiration_filter', 'true', 'Filter expired events from responses', 'user', 'boolean', 0),
+('expiration_grace_period', '300', 'Grace period for clock skew (seconds)', 'user', 'integer', 0),
+
+-- Subscription limits
+('max_subscriptions_per_client', '20', 'Max subscriptions per client', 'user', 'integer', 0),
+('max_total_subscriptions', '5000', 'Max total concurrent subscriptions', 'user', 'integer', 0),
+('subscription_id_max_length', '64', 'Maximum subscription ID length', 'user', 'integer', 0),
+
+-- Event processing limits
+('max_event_tags', '100', 'Maximum tags per event', 'user', 'integer', 0),
+('max_content_length', '8196', 'Maximum content length', 'user', 'integer', 0),
+('max_message_length', '16384', 'Maximum message length', 'user', 'integer', 0),
+
+-- Performance settings
+('default_limit', '500', 'Default query limit', 'user', 'integer', 0),
+('max_limit', '5000', 'Maximum query limit', 'user', 'integer', 0);
+```
+
+### Runtime Statistics
+
+```sql
+INSERT OR IGNORE INTO server_config (key, value, description, config_type, data_type) VALUES
+-- Runtime statistics (updated by server)
+('server_start_time', '0', 'Server startup timestamp', 'runtime', 'integer'),
+('total_events_processed', '0', 'Total events processed', 'runtime', 'integer'),
+('total_subscriptions_created', '0', 'Total subscriptions created', 'runtime', 'integer'),
+('current_connections', '0', 'Current active connections', 'runtime', 'integer'),
+('database_size_bytes', '0', 'Database file size in bytes', 'runtime', 'integer');
+```
+
+## Configuration Views
+
+### Active Configuration View
+
+```sql
+CREATE VIEW active_config AS
+SELECT 
+    key,
+    value,
+    description,
+    config_type,
+    data_type,
+    requires_restart,
+    updated_at
+FROM server_config
+WHERE config_type IN ('system', 'user')
+ORDER BY config_type, key;
+```
+
+### Runtime Statistics View
+
+```sql
+CREATE VIEW runtime_stats AS
+SELECT 
+    key,
+    value,
+    description,
+    updated_at
+FROM server_config
+WHERE config_type = 'runtime'
+ORDER BY key;
+```
+
+### Configuration Change Summary
+
+```sql
+CREATE VIEW recent_config_changes AS
+SELECT 
+    ch.config_key,
+    sc.description,
+    ch.old_value,
+    ch.new_value,
+    ch.changed_by,
+    ch.change_reason,
+    ch.changed_at
+FROM config_history ch
+JOIN server_config sc ON ch.config_key = sc.key
+ORDER BY ch.changed_at DESC
+LIMIT 50;
+```
+
+## Validation Rules Format
+
+Configuration validation rules are stored as JSON strings in the `validation_rules` column:
+
+```json
+{
+  "type": "integer",
+  "min": 1,
+  "max": 65535,
+  "required": true
+}
+```
+
+```json
+{
+  "type": "string",
+  "pattern": "^[0-9a-fA-F]{64}$",
+  "required": false,
+  "description": "64-character hex string"
+}
+```
+
+```json
+{
+  "type": "boolean",
+  "required": true
+}
+```
+
+## Migration Strategy
+
+1. **Phase 1**: Add configuration tables to existing schema
+2. **Phase 2**: Populate with current hardcoded values
+3. **Phase 3**: Update application code to read from database
+4. **Phase 4**: Add file-based configuration loading
+5. **Phase 5**: Remove hardcoded defaults and environment variable fallbacks
+
+## Integration Points
+
+- **Startup**: Load configuration from file → database → apply to application
+- **Runtime**: Read configuration values from database cache
+- **Updates**: Write changes to database → optionally update file
+- **Validation**: Validate all configuration changes before applying
+- **History**: Track all configuration changes for audit purposes

docs/file_config_design.md

@@ -0,0 +1,493 @@
+# File-Based Configuration Architecture Design
+
+## Overview
+This document outlines the XDG-compliant file-based configuration system for the C Nostr Relay, following the Ginxsom admin system approach using signed Nostr events.
+
+## XDG Base Directory Specification Compliance
+
+### File Location Strategy
+
+**Primary Location:**
+```
+$XDG_CONFIG_HOME/c-relay/c_relay_config_event.json
+```
+
+**Fallback Location:**
+```
+$HOME/.config/c-relay/c_relay_config_event.json
+```
+
+**System-wide Fallback:**
+```
+/etc/c-relay/c_relay_config_event.json
+```
+
+### Directory Structure
+```
+$XDG_CONFIG_HOME/c-relay/
+├── c_relay_config_event.json          # Main configuration file
+├── backup/                            # Configuration backups
+│   ├── c_relay_config_event.json.bak
+│   └── c_relay_config_event.20241205.json
+└── validation/                        # Validation logs
+    └── config_validation.log
+```
+
+## Configuration File Format
+
+### Signed Nostr Event Structure
+
+The configuration file contains a signed Nostr event (kind 33334) with relay configuration:
+
+```json
+{
+  "kind": 33334,
+  "created_at": 1704067200,
+  "tags": [
+    ["relay_name", "C Nostr Relay"],
+    ["relay_description", "High-performance C Nostr relay with SQLite storage"],
+    ["relay_port", "8888"],
+    ["database_path", "db/c_nostr_relay.db"],
+    ["admin_pubkey", ""],
+    ["admin_enabled", "false"],
+    
+    ["pow_enabled", "true"],
+    ["pow_min_difficulty", "0"],
+    ["pow_mode", "basic"],
+    
+    ["expiration_enabled", "true"],
+    ["expiration_strict", "true"],
+    ["expiration_filter", "true"],
+    ["expiration_grace_period", "300"],
+    
+    ["max_subscriptions_per_client", "20"],
+    ["max_total_subscriptions", "5000"],
+    ["max_connections", "100"],
+    
+    ["relay_contact", ""],
+    ["relay_pubkey", ""],
+    ["relay_software", "https://git.laantungir.net/laantungir/c-relay.git"],
+    ["relay_version", "0.2.0"],
+    
+    ["max_event_tags", "100"],
+    ["max_content_length", "8196"],
+    ["max_message_length", "16384"],
+    ["default_limit", "500"],
+    ["max_limit", "5000"]
+  ],
+  "content": "C Nostr Relay configuration event",
+  "pubkey": "admin_public_key_hex_64_chars",
+  "id": "computed_event_id_hex_64_chars",
+  "sig": "computed_signature_hex_128_chars"
+}
+```
+
+### Event Kind Definition
+
+**Kind 33334**: C Nostr Relay Configuration Event
+- Parameterized replaceable event
+- Must be signed by authorized admin pubkey
+- Contains relay configuration as tags
+- Validation required on load
+
+## Configuration Loading Architecture
+
+### Loading Priority Chain
+
+1. **Command Line Arguments** (highest priority)
+2. **File-based Configuration** (signed Nostr event)
+3. **Database Configuration** (persistent storage)
+4. **Environment Variables** (compatibility mode)
+5. **Hardcoded Defaults** (fallback)
+
+### Loading Process Flow
+
+```mermaid
+flowchart TD
+    A[Server Startup] --> B[Get Config File Path]
+    B --> C{File Exists?}
+    C -->|No| D[Check Database Config]
+    C -->|Yes| E[Load & Parse JSON]
+    E --> F[Validate Event Structure]
+    F --> G{Valid Event?}
+    G -->|No| H[Log Error & Use Database]
+    G -->|Yes| I[Verify Event Signature]
+    I --> J{Signature Valid?}
+    J -->|No| K[Log Error & Use Database]
+    J -->|Yes| L[Extract Configuration Tags]
+    L --> M[Apply to Database]
+    M --> N[Apply to Application]
+    D --> O[Load from Database]
+    H --> O
+    K --> O
+    O --> P[Apply Environment Variable Overrides]
+    P --> Q[Apply Command Line Overrides]
+    Q --> N
+    N --> R[Server Ready]
+```
+
+## C Implementation Architecture
+
+### Core Data Structures
+
+```c
+// Configuration file management
+typedef struct {
+    char file_path[512];
+    char file_hash[65];      // SHA256 hash
+    time_t last_modified;
+    time_t last_loaded;
+    int validation_status;   // 0=valid, 1=invalid, 2=unverified
+    char validation_error[256];
+} config_file_info_t;
+
+// Configuration event structure
+typedef struct {
+    char event_id[65];
+    char pubkey[65];
+    char signature[129];
+    long created_at;
+    int kind;
+    cJSON* tags;
+    char* content;
+} config_event_t;
+
+// Configuration management context
+typedef struct {
+    config_file_info_t file_info;
+    config_event_t event;
+    int loaded_from_file;
+    int loaded_from_database;
+    char admin_pubkey[65];
+    time_t load_timestamp;
+} config_context_t;
+```
+
+### Core Function Signatures
+
+```c
+// XDG path resolution
+int get_config_file_path(char* path, size_t path_size);
+int create_config_directories(const char* config_path);
+
+// File operations
+int load_config_from_file(const char* config_path, config_context_t* ctx);
+int save_config_to_file(const char* config_path, const config_event_t* event);
+int backup_config_file(const char* config_path);
+
+// Event validation
+int validate_config_event_structure(const cJSON* event);
+int verify_config_event_signature(const config_event_t* event, const char* admin_pubkey);
+int validate_config_tag_values(const cJSON* tags);
+
+// Configuration extraction and application
+int extract_config_from_tags(const cJSON* tags, config_context_t* ctx);
+int apply_config_to_database(const config_context_t* ctx);
+int apply_config_to_globals(const config_context_t* ctx);
+
+// File monitoring and updates
+int monitor_config_file_changes(const char* config_path);
+int reload_config_on_change(config_context_t* ctx);
+
+// Error handling and logging
+int log_config_validation_error(const char* config_key, const char* error);
+int log_config_load_event(const config_context_t* ctx, const char* source);
+```
+
+## Configuration Validation Rules
+
+### Event Structure Validation
+
+1. **Required Fields**: `kind`, `created_at`, `tags`, `content`, `pubkey`, `id`, `sig`
+2. **Kind Validation**: Must be exactly 33334
+3. **Timestamp Validation**: Must be reasonable (not too old, not future)
+4. **Tags Format**: Array of string arrays `[["key", "value"], ...]`
+5. **Signature Verification**: Must be signed by authorized admin pubkey
+
+### Configuration Value Validation
+
+```c
+typedef struct {
+    char* key;
+    char* data_type;        // "string", "integer", "boolean", "json"
+    char* validation_rule;  // JSON validation rule
+    int required;
+    char* default_value;
+} config_validation_rule_t;
+
+static config_validation_rule_t validation_rules[] = {
+    {"relay_port", "integer", "{\"min\": 1, \"max\": 65535}", 1, "8888"},
+    {"pow_min_difficulty", "integer", "{\"min\": 0, \"max\": 64}", 1, "0"},
+    {"expiration_grace_period", "integer", "{\"min\": 0, \"max\": 86400}", 1, "300"},
+    {"admin_pubkey", "string", "{\"pattern\": \"^[0-9a-fA-F]{64}$\"}", 0, ""},
+    {"pow_enabled", "boolean", "{}", 1, "true"},
+    // ... more rules
+};
+```
+
+### Security Validation
+
+1. **Admin Pubkey Verification**: Only configured admin pubkeys can create config events
+2. **Event ID Verification**: Event ID must match computed hash
+3. **Signature Verification**: Signature must be valid for the event and pubkey
+4. **Timestamp Validation**: Prevent replay attacks with old events
+5. **File Permission Checks**: Config files should have appropriate permissions
+
+## File Management Features
+
+### Configuration File Operations
+
+**File Creation:**
+- Generate initial configuration file with default values
+- Sign with admin private key
+- Set appropriate file permissions (600 - owner read/write only)
+
+**File Updates:**
+- Create backup of existing file
+- Validate new configuration
+- Atomic file replacement (write to temp, then rename)
+- Update file metadata cache
+
+**File Monitoring:**
+- Watch for file system changes using inotify (Linux)
+- Reload configuration automatically when file changes
+- Validate changes before applying
+- Log all configuration reload events
+
+### Backup and Recovery
+
+**Automatic Backups:**
+```
+$XDG_CONFIG_HOME/c-relay/backup/
+├── c_relay_config_event.json.bak           # Last working config
+├── c_relay_config_event.20241205-143022.json # Timestamped backups
+└── c_relay_config_event.20241204-091530.json
+```
+
+**Recovery Process:**
+1. Detect corrupted or invalid config file
+2. Attempt to load from `.bak` backup
+3. If backup fails, generate default configuration
+4. Log recovery actions for audit
+
+## Integration with Database Schema
+
+### File-Database Synchronization
+
+**On File Load:**
+1. Parse and validate file-based configuration
+2. Extract configuration values from event tags
+3. Update database `server_config` table
+4. Record file metadata in `config_file_cache` table
+5. Log configuration changes in `config_history` table
+
+**Configuration Priority Resolution:**
+```c
+char* get_config_value(const char* key, const char* default_value) {
+    // Priority: CLI args > File config > DB config > Env vars > Default
+    char* value = NULL;
+    
+    // 1. Check command line overrides (if implemented)
+    value = get_cli_override(key);
+    if (value) return value;
+    
+    // 2. Check database (updated from file)
+    value = get_database_config(key);
+    if (value) return value;
+    
+    // 3. Check environment variables (compatibility)
+    value = get_env_config(key);
+    if (value) return value;
+    
+    // 4. Return default
+    return strdup(default_value);
+}
+```
+
+## Error Handling and Recovery
+
+### Validation Error Handling
+
+```c
+typedef enum {
+    CONFIG_ERROR_NONE = 0,
+    CONFIG_ERROR_FILE_NOT_FOUND = 1,
+    CONFIG_ERROR_PARSE_FAILED = 2,
+    CONFIG_ERROR_INVALID_STRUCTURE = 3,
+    CONFIG_ERROR_SIGNATURE_INVALID = 4,
+    CONFIG_ERROR_UNAUTHORIZED = 5,
+    CONFIG_ERROR_VALUE_INVALID = 6,
+    CONFIG_ERROR_IO_ERROR = 7
+} config_error_t;
+
+typedef struct {
+    config_error_t error_code;
+    char error_message[256];
+    char config_key[64];
+    char invalid_value[128];
+    time_t error_timestamp;
+} config_error_info_t;
+```
+
+### Graceful Degradation
+
+**File Load Failure:**
+1. Log detailed error information
+2. Fall back to database configuration
+3. Continue operation with last known good config
+4. Set service status to "degraded" mode
+
+**Validation Failure:**
+1. Log validation errors with specific details
+2. Skip invalid configuration items
+3. Use default values for failed items
+4. Continue with partial configuration
+
+**Permission Errors:**
+1. Log permission issues
+2. Attempt to use fallback locations
+3. Generate temporary config if needed
+4. Alert administrator via logs
+
+## Configuration Update Process
+
+### Safe Configuration Updates
+
+**Atomic Update Process:**
+1. Create backup of current configuration
+2. Write new configuration to temporary file
+3. Validate new configuration completely
+4. If valid, rename temporary file to active config
+5. Update database with new values
+6. Apply changes to running server
+7. Log successful update
+
+**Rollback Process:**
+1. Detect invalid configuration at startup
+2. Restore from backup file
+3. Log rollback event
+4. Continue with previous working configuration
+
+### Hot Reload Support
+
+**File Change Detection:**
+```c
+int monitor_config_file_changes(const char* config_path) {
+    // Use inotify on Linux to watch file changes
+    int inotify_fd = inotify_init();
+    int watch_fd = inotify_add_watch(inotify_fd, config_path, IN_MODIFY | IN_MOVED_TO);
+    
+    // Monitor in separate thread
+    // On change: validate -> apply -> log
+    return 0;
+}
+```
+
+**Runtime Configuration Updates:**
+- Reload configuration on file change
+- Apply non-restart-required changes immediately
+- Queue restart-required changes for next restart
+- Notify operators of configuration changes
+
+## Security Considerations
+
+### Access Control
+
+**File Permissions:**
+- Config files: 600 (owner read/write only)
+- Directories: 700 (owner access only)
+- Backup files: 600 (owner read/write only)
+
+**Admin Key Management:**
+- Admin private keys never stored in config files
+- Only admin pubkeys stored for verification
+- Support for multiple admin pubkeys
+- Key rotation support
+
+### Signature Validation
+
+**Event Signature Verification:**
+```c
+int verify_config_event_signature(const config_event_t* event, const char* admin_pubkey) {
+    // 1. Reconstruct event for signing (without id and sig)
+    // 2. Compute event ID and verify against stored ID
+    // 3. Verify signature using admin pubkey
+    // 4. Check admin pubkey authorization
+    return NOSTR_SUCCESS;
+}
+```
+
+**Anti-Replay Protection:**
+- Configuration events must be newer than current
+- Event timestamps validated against reasonable bounds
+- Configuration history prevents replay attacks
+
+## Implementation Phases
+
+### Phase 1: Basic File Support
+- XDG path resolution
+- File loading and parsing
+- Basic validation
+- Database integration
+
+### Phase 2: Security Features
+- Event signature verification
+- Admin pubkey management
+- File permission checks
+- Error handling
+
+### Phase 3: Advanced Features
+- Hot reload support
+- Automatic backups
+- Configuration utilities
+- Interactive setup
+
+### Phase 4: Monitoring & Management
+- Configuration change monitoring
+- Advanced validation rules
+- Configuration audit logging
+- Management utilities
+
+## Configuration Generation Utilities
+
+### Interactive Setup Script
+
+```bash
+#!/bin/bash
+# scripts/setup_config.sh - Interactive configuration setup
+
+create_initial_config() {
+    echo "=== C Nostr Relay Initial Configuration ==="
+    
+    # Collect basic information
+    read -p "Relay name [C Nostr Relay]: " relay_name
+    read -p "Admin public key (hex): " admin_pubkey
+    read -p "Server port [8888]: " server_port
+    
+    # Generate signed configuration event
+    ./scripts/generate_config.sh \
+        --admin-key "$admin_pubkey" \
+        --relay-name "${relay_name:-C Nostr Relay}" \
+        --port "${server_port:-8888}" \
+        --output "$XDG_CONFIG_HOME/c-relay/c_relay_config_event.json"
+}
+```
+
+### Configuration Validation Utility
+
+```bash
+#!/bin/bash
+# scripts/validate_config.sh - Validate configuration file
+
+validate_config_file() {
+    local config_file="$1"
+    
+    # Check file exists and is readable
+    # Validate JSON structure
+    # Verify event signature
+    # Check configuration values
+    # Report validation results
+}
+```
+
+This comprehensive file-based configuration design provides a robust, secure, and maintainable system that follows industry standards while integrating seamlessly with the existing C Nostr Relay architecture.

make_and_restart_relay.sh

@@ -5,6 +5,53 @@
 
 echo "=== C Nostr Relay Build and Restart Script ==="
 
+# Parse command line arguments
+PRESERVE_CONFIG=false
+HELP=false
+
+while [[ $# -gt 0 ]]; do
+    case $1 in
+        --preserve-config|-p)
+            PRESERVE_CONFIG=true
+            shift
+            ;;
+        --help|-h)
+            HELP=true
+            shift
+            ;;
+        *)
+            echo "Unknown option: $1"
+            HELP=true
+            shift
+            ;;
+    esac
+done
+
+# Show help
+if [ "$HELP" = true ]; then
+    echo "Usage: $0 [OPTIONS]"
+    echo ""
+    echo "Options:"
+    echo "  --preserve-config  Keep existing configuration file (don't regenerate)"
+    echo "  --help, -h         Show this help message"
+    echo ""
+    echo "Default behavior: Automatically regenerates configuration file on each build"
+    echo "                 for development purposes"
+    exit 0
+fi
+
+# Handle configuration file regeneration
+CONFIG_FILE="$HOME/.config/c-relay/c_relay_config_event.json"
+if [ "$PRESERVE_CONFIG" = false ] && [ -f "$CONFIG_FILE" ]; then
+    echo "Removing old configuration file to trigger regeneration..."
+    rm -f "$CONFIG_FILE"
+    echo "✓ Configuration file removed - will be regenerated with latest database values"
+elif [ "$PRESERVE_CONFIG" = true ] && [ -f "$CONFIG_FILE" ]; then
+    echo "Preserving existing configuration file as requested"
+elif [ ! -f "$CONFIG_FILE" ]; then
+    echo "No existing configuration file found - will generate new one"
+fi
+
 # Build the project first
 echo "Building project..."
 make clean all
@@ -90,6 +137,19 @@ if ps -p "$RELAY_PID" >/dev/null 2>&1; then
     # Save PID for debugging
     echo $RELAY_PID > relay.pid
 
+    # Check if a new private key was generated and display it
+    sleep 1  # Give relay time to write initial logs
+    if grep -q "GENERATED RELAY ADMIN PRIVATE KEY" relay.log 2>/dev/null; then
+        echo "=== IMPORTANT: NEW ADMIN PRIVATE KEY GENERATED ==="
+        echo ""
+        # Extract and display the private key section from the log
+        grep -A 8 -B 2 "GENERATED RELAY ADMIN PRIVATE KEY" relay.log | head -n 12
+        echo ""
+        echo "⚠️  SAVE THIS PRIVATE KEY SECURELY - IT CONTROLS YOUR RELAY!"
+        echo "⚠️  This key is also logged in relay.log for reference"
+        echo ""
+    fi
+
     echo "=== Relay server running in background ==="
     echo "To kill relay: pkill -f 'c_relay_'"
     echo "To check status: ps aux | grep c_relay_"

relay.log

@@ -1,117 +0,0 @@
-=== C Nostr Relay Server ===
-[SUCCESS] Database connection established
-[SUCCESS] Relay information initialized with default values
-[INFO] Initializing NIP-13 Proof of Work configuration
-[INFO] PoW Configuration: enabled=true, min_difficulty=0, validation_flags=0x1, mode=full
-[INFO] Starting relay server...
-[INFO] Starting libwebsockets-based Nostr relay server...
-[SUCCESS] WebSocket relay started on ws://127.0.0.1:8888
-[INFO] HTTP request received
-[INFO] Handling NIP-11 relay information request
-[SUCCESS] NIP-11 relay information served successfully
-[INFO] HTTP request received
-[INFO] Handling NIP-11 relay information request
-[SUCCESS] NIP-11 relay information served successfully
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Handling EVENT message with full NIP-01 validation
-[SUCCESS] Event stored in database
-[SUCCESS] Event validated and stored successfully
-[INFO] WebSocket connection closed
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Handling EVENT message with full NIP-01 validation
-[INFO] PoW validated: difficulty=10, target=8, nonce=1839
-[SUCCESS] Event stored in database
-[SUCCESS] Event validated and stored successfully
-[INFO] WebSocket connection closed
-[INFO] HTTP request received
-[INFO] Handling NIP-11 relay information request
-[SUCCESS] NIP-11 relay information served successfully
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] WebSocket connection closed
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Handling EVENT message with full NIP-01 validation
-[INFO] PoW validated: difficulty=21, target=20, nonce=776797
-[SUCCESS] Event stored in database
-[SUCCESS] Event validated and stored successfully
-[INFO] WebSocket connection closed
-[INFO] HTTP request received
-[INFO] Handling NIP-11 relay information request
-[SUCCESS] NIP-11 relay information served successfully
-[INFO] HTTP request received
-[INFO] Handling NIP-11 relay information request
-[SUCCESS] NIP-11 relay information served successfully
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Handling EVENT message with full NIP-01 validation
-[SUCCESS] Event stored in database
-[SUCCESS] Event validated and stored successfully
-[INFO] WebSocket connection closed
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Handling EVENT message with full NIP-01 validation
-[INFO] PoW validated: difficulty=8, target=8, nonce=385
-[SUCCESS] Event stored in database
-[SUCCESS] Event validated and stored successfully
-[INFO] WebSocket connection closed
-[INFO] HTTP request received
-[INFO] Handling NIP-11 relay information request
-[SUCCESS] NIP-11 relay information served successfully
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] Received WebSocket message
-[INFO] WebSocket connection closed
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Handling EVENT message with full NIP-01 validation
-[INFO] PoW validated: difficulty=21, target=20, nonce=776797
-[WARNING] Event already exists in database
-[SUCCESS] Event validated and stored successfully
-[INFO] WebSocket connection closed
-[INFO] HTTP request received
-[INFO] Handling NIP-11 relay information request
-[SUCCESS] NIP-11 relay information served successfully
-[INFO] HTTP request received
-[INFO] Handling NIP-11 relay information request
-[SUCCESS] NIP-11 relay information served successfully
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Handling EVENT message with full NIP-01 validation
-[SUCCESS] Event stored in database
-[SUCCESS] Event validated and stored successfully
-[INFO] WebSocket connection closed
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Handling EVENT message with full NIP-01 validation
-[INFO] PoW validated: difficulty=8, target=8, nonce=1669
-[SUCCESS] Event stored in database
-[SUCCESS] Event validated and stored successfully
-[INFO] WebSocket connection closed
-[INFO] HTTP request received
-[INFO] Handling NIP-11 relay information request
-[SUCCESS] NIP-11 relay information served successfully
-[INFO] WebSocket connection established
-[INFO] Received WebSocket message
-[INFO] Handling EVENT message with full NIP-01 validation
-[INFO] PoW validated: difficulty=21, target=20, nonce=776797
-[WARNING] Event already exists in database
-[SUCCESS] Event validated and stored successfully
-[INFO] WebSocket connection closed

relay.pid

@@ -1 +1 @@
-736301
+871512

src/config.h

@@ -0,0 +1,223 @@
+#ifndef CONFIG_H
+#define CONFIG_H
+
+#include <sqlite3.h>
+#include <time.h>
+#include <stddef.h>
+#include <cjson/cJSON.h>
+
+// Configuration system constants
+#define CONFIG_KEY_MAX_LENGTH 64
+#define CONFIG_VALUE_MAX_LENGTH 512
+#define CONFIG_DESCRIPTION_MAX_LENGTH 256
+#define CONFIG_XDG_DIR_NAME "c-relay"
+#define CONFIG_FILE_NAME "c_relay_config_event.json"
+#define CONFIG_PRIVKEY_ENV "C_RELAY_CONFIG_PRIVKEY"
+#define NOSTR_PUBKEY_HEX_LENGTH 64
+#define NOSTR_PRIVKEY_HEX_LENGTH 64
+#define NOSTR_EVENT_ID_HEX_LENGTH 64
+#define NOSTR_SIGNATURE_HEX_LENGTH 128
+
+// Protocol and implementation constants (hardcoded - should NOT be configurable)
+#define SUBSCRIPTION_ID_MAX_LENGTH 64
+#define CLIENT_IP_MAX_LENGTH 64
+#define RELAY_NAME_MAX_LENGTH 128
+#define RELAY_DESCRIPTION_MAX_LENGTH 1024
+#define RELAY_URL_MAX_LENGTH 256
+#define RELAY_CONTACT_MAX_LENGTH 128
+#define RELAY_PUBKEY_MAX_LENGTH 65
+
+// Default configuration values (used as fallbacks if database config fails)
+#define DEFAULT_DATABASE_PATH "db/c_nostr_relay.db"
+#define DEFAULT_PORT 8888
+#define DEFAULT_HOST "127.0.0.1"
+#define MAX_CLIENTS 100
+#define MAX_SUBSCRIPTIONS_PER_CLIENT 20
+#define MAX_TOTAL_SUBSCRIPTIONS 5000
+#define MAX_FILTERS_PER_SUBSCRIPTION 10
+
+// Configuration types
+typedef enum {
+    CONFIG_TYPE_SYSTEM = 0,
+    CONFIG_TYPE_USER = 1,
+    CONFIG_TYPE_RUNTIME = 2
+} config_type_t;
+
+// Configuration data types
+typedef enum {
+    CONFIG_DATA_STRING = 0,
+    CONFIG_DATA_INTEGER = 1,
+    CONFIG_DATA_BOOLEAN = 2,
+    CONFIG_DATA_JSON = 3
+} config_data_type_t;
+
+// Configuration validation result
+typedef enum {
+    CONFIG_VALID = 0,
+    CONFIG_INVALID_TYPE = 1,
+    CONFIG_INVALID_RANGE = 2,
+    CONFIG_INVALID_FORMAT = 3,
+    CONFIG_MISSING_REQUIRED = 4
+} config_validation_result_t;
+
+// Configuration entry structure
+typedef struct {
+    char key[CONFIG_KEY_MAX_LENGTH];
+    char value[CONFIG_VALUE_MAX_LENGTH];
+    char description[CONFIG_DESCRIPTION_MAX_LENGTH];
+    config_type_t config_type;
+    config_data_type_t data_type;
+    int is_sensitive;
+    int requires_restart;
+    time_t created_at;
+    time_t updated_at;
+} config_entry_t;
+
+// Configuration manager state
+typedef struct {
+    sqlite3* db;
+    sqlite3_stmt* get_config_stmt;
+    sqlite3_stmt* set_config_stmt;
+    sqlite3_stmt* log_change_stmt;
+    
+    // Configuration loading status
+    int file_config_loaded;
+    int database_config_loaded;
+    time_t last_reload;
+    
+    // XDG configuration directory
+    char config_dir_path[512];
+    char config_file_path[600];
+} config_manager_t;
+
+// Global configuration manager instance
+extern config_manager_t g_config_manager;
+
+// ================================
+// CORE CONFIGURATION FUNCTIONS
+// ================================
+
+// Initialize configuration system
+int init_configuration_system(void);
+
+// Cleanup configuration system
+void cleanup_configuration_system(void);
+
+// Load configuration from all sources (file -> database -> defaults)
+int load_configuration(void);
+
+// Apply loaded configuration to global variables
+int apply_configuration_to_globals(void);
+
+// ================================
+// DATABASE CONFIGURATION FUNCTIONS
+// ================================
+
+// Initialize database prepared statements
+int init_config_database_statements(void);
+
+// Get configuration value from database
+int get_database_config(const char* key, char* value, size_t value_size);
+
+// Set configuration value in database
+int set_database_config(const char* key, const char* new_value, const char* changed_by);
+
+// Load all configuration from database
+int load_config_from_database(void);
+
+// ================================
+// FILE CONFIGURATION FUNCTIONS
+// ================================
+
+// Get XDG configuration directory path
+int get_xdg_config_dir(char* path, size_t path_size);
+
+// Check if configuration file exists
+int config_file_exists(void);
+
+// Load configuration from file
+int load_config_from_file(void);
+
+// Validate and apply Nostr configuration event
+int validate_and_apply_config_event(const cJSON* event);
+
+// Validate Nostr event structure
+int validate_nostr_event_structure(const cJSON* event);
+
+// Validate configuration tags array
+int validate_config_tags(const cJSON* tags);
+
+// Extract and apply configuration tags to database
+int extract_and_apply_config_tags(const cJSON* tags);
+
+// ================================
+// CONFIGURATION ACCESS FUNCTIONS
+// ================================
+
+// Get configuration value (checks all sources: file -> database -> environment -> defaults)
+const char* get_config_value(const char* key);
+
+// Get configuration value as integer
+int get_config_int(const char* key, int default_value);
+
+// Get configuration value as boolean
+int get_config_bool(const char* key, int default_value);
+
+// Set configuration value (updates database)
+int set_config_value(const char* key, const char* value);
+
+// ================================
+// CONFIGURATION VALIDATION
+// ================================
+
+// Validate configuration value
+config_validation_result_t validate_config_value(const char* key, const char* value);
+
+// Log validation error
+void log_config_validation_error(const char* key, const char* value, const char* error);
+
+// ================================
+// UTILITY FUNCTIONS
+// ================================
+
+// Convert config type enum to string
+const char* config_type_to_string(config_type_t type);
+
+// Convert config data type enum to string
+const char* config_data_type_to_string(config_data_type_t type);
+
+// Convert string to config type enum
+config_type_t string_to_config_type(const char* str);
+
+// Convert string to config data type enum
+config_data_type_t string_to_config_data_type(const char* str);
+
+// Check if configuration key requires restart
+int config_requires_restart(const char* key);
+
+// ================================
+// NOSTR EVENT GENERATION FUNCTIONS
+// ================================
+
+// Generate configuration file with valid Nostr event if it doesn't exist
+int generate_config_file_if_missing(void);
+
+// Create a valid Nostr configuration event from database values
+cJSON* create_config_nostr_event(const char* privkey_hex);
+
+// Generate a random private key (32 bytes as hex string)
+int generate_random_privkey(char* privkey_hex, size_t buffer_size);
+
+// Derive public key from private key (using secp256k1)
+int derive_pubkey_from_privkey(const char* privkey_hex, char* pubkey_hex, size_t buffer_size);
+
+// Create Nostr event ID (SHA256 of serialized event data)
+int create_nostr_event_id(const cJSON* event, char* event_id_hex, size_t buffer_size);
+
+// Sign Nostr event (using secp256k1 Schnorr signature)
+int sign_nostr_event(const cJSON* event, const char* privkey_hex, char* signature_hex, size_t buffer_size);
+
+// Write configuration event to file
+int write_config_event_to_file(const cJSON* event);
+
+#endif // CONFIG_H

src/main.c

@@ -15,26 +15,7 @@
 #include "../nostr_core_lib/cjson/cJSON.h"
 #include "../nostr_core_lib/nostr_core/nostr_core.h"
 #include "../nostr_core_lib/nostr_core/nip013.h"  // NIP-13: Proof of Work
-
-// Server Configuration
-#define DEFAULT_PORT 8888
-#define DEFAULT_HOST "127.0.0.1"
-#define DATABASE_PATH "db/c_nostr_relay.db"
-#define MAX_CLIENTS 100
-
-// Persistent subscription system configuration
-#define MAX_SUBSCRIPTIONS_PER_CLIENT 20
-#define MAX_TOTAL_SUBSCRIPTIONS 5000
-#define MAX_FILTERS_PER_SUBSCRIPTION 10
-#define SUBSCRIPTION_ID_MAX_LENGTH 64
-#define CLIENT_IP_MAX_LENGTH 64
-
-// NIP-11 relay information configuration
-#define RELAY_NAME_MAX_LENGTH 128
-#define RELAY_DESCRIPTION_MAX_LENGTH 1024
-#define RELAY_URL_MAX_LENGTH 256
-#define RELAY_CONTACT_MAX_LENGTH 128
-#define RELAY_PUBKEY_MAX_LENGTH 65  // 64 hex chars + null terminator
+#include "config.h"  // Configuration management system
 
 // Color constants for logging
 #define RED     "\033[31m"
@@ -45,7 +26,7 @@
 #define RESET   "\033[0m"
 
 // Global state
-static sqlite3* g_db = NULL;
+sqlite3* g_db = NULL;  // Non-static so config.c can access it
 static int g_server_running = 1;
 static struct lws_context *ws_context = NULL;
 
@@ -97,6 +78,24 @@ static struct pow_config g_pow_config = {
     .anti_spam_mode = 0            // Basic validation by default
 };
 
+// NIP-40 Expiration configuration structure
+struct expiration_config {
+    int enabled;                    // 0 = disabled, 1 = enabled
+    int strict_mode;                // 1 = reject expired events on submission
+    int filter_responses;           // 1 = filter expired events from responses
+    int delete_expired;             // 1 = delete expired events from DB (future feature)
+    long grace_period;              // Grace period in seconds for clock skew
+};
+
+// Global expiration configuration instance
+static struct expiration_config g_expiration_config = {
+    .enabled = 1,                   // Enable expiration handling by default
+    .strict_mode = 1,               // Reject expired events on submission by default
+    .filter_responses = 1,          // Filter expired events from responses by default
+    .delete_expired = 0,            // Don't delete by default (keep for audit)
+    .grace_period = 300             // 5 minutes grace period for clock skew
+};
+
 
 /////////////////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////////////////
@@ -170,8 +169,8 @@ static subscription_manager_t g_subscription_manager = {
     .active_subscriptions = NULL,
     .subscriptions_lock = PTHREAD_MUTEX_INITIALIZER,
     .total_subscriptions = 0,
-    .max_subscriptions_per_client = MAX_SUBSCRIPTIONS_PER_CLIENT,
-    .max_total_subscriptions = MAX_TOTAL_SUBSCRIPTIONS,
+    .max_subscriptions_per_client = MAX_SUBSCRIPTIONS_PER_CLIENT, // Will be updated from config
+    .max_total_subscriptions = MAX_TOTAL_SUBSCRIPTIONS, // Will be updated from config
     .total_created = 0,
     .total_events_broadcast = 0
 };
@@ -182,6 +181,9 @@ void log_success(const char* message);
 void log_error(const char* message);
 void log_warning(const char* message);
 
+// Forward declaration for subscription manager configuration
+void update_subscription_manager_config(void);
+
 // Forward declarations for subscription database logging
 void log_subscription_created(const subscription_t* sub);
 void log_subscription_closed(const char* sub_id, const char* client_ip, const char* reason);
@@ -217,6 +219,12 @@ int handle_nip11_http_request(struct lws* wsi, const char* accept_header);
 void init_pow_config();
 int validate_event_pow(cJSON* event, char* error_message, size_t error_size);
 
+// Forward declarations for NIP-40 expiration handling
+void init_expiration_config();
+long extract_expiration_timestamp(cJSON* tags);
+int is_event_expired(cJSON* event, time_t current_time);
+int validate_event_expiration(cJSON* event, char* error_message, size_t error_size);
+
 
 /////////////////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////////////////
@@ -651,6 +659,19 @@ int broadcast_event_to_subscriptions(cJSON* event) {
         return 0;
     }
     
+    // Check if event is expired and should not be broadcast (NIP-40)
+    if (g_expiration_config.enabled && g_expiration_config.filter_responses) {
+        time_t current_time = time(NULL);
+        if (is_event_expired(event, current_time)) {
+            char debug_msg[256];
+            cJSON* event_id_obj = cJSON_GetObjectItem(event, "id");
+            const char* event_id = event_id_obj ? cJSON_GetStringValue(event_id_obj) : "unknown";
+            snprintf(debug_msg, sizeof(debug_msg), "Skipping broadcast of expired event: %.16s", event_id);
+            log_info(debug_msg);
+            return 0; // Don't broadcast expired events
+        }
+    }
+    
     int broadcasts = 0;
     
     pthread_mutex_lock(&g_subscription_manager.subscriptions_lock);
@@ -918,6 +939,19 @@ void log_warning(const char* message) {
     fflush(stdout);
 }
 
+// Update subscription manager configuration from config system
+void update_subscription_manager_config(void) {
+    g_subscription_manager.max_subscriptions_per_client = get_config_int("max_subscriptions_per_client", MAX_SUBSCRIPTIONS_PER_CLIENT);
+    g_subscription_manager.max_total_subscriptions = get_config_int("max_total_subscriptions", MAX_TOTAL_SUBSCRIPTIONS);
+    
+    char config_msg[256];
+    snprintf(config_msg, sizeof(config_msg),
+             "Subscription limits: max_per_client=%d, max_total=%d",
+             g_subscription_manager.max_subscriptions_per_client,
+             g_subscription_manager.max_total_subscriptions);
+    log_info(config_msg);
+}
+
 // Signal handler for graceful shutdown
 void signal_handler(int sig) {
     if (sig == SIGINT || sig == SIGTERM) {
@@ -1251,13 +1285,47 @@ int mark_event_as_deleted(const char* event_id, const char* deletion_event_id, c
 /////////////////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////////////////
 
-// Initialize relay information with default values
+// Initialize relay information using configuration system
 void init_relay_info() {
-    // Set default relay information
-    strncpy(g_relay_info.name, "C Nostr Relay", sizeof(g_relay_info.name) - 1);
-    strncpy(g_relay_info.description, "A high-performance Nostr relay implemented in C with SQLite storage", sizeof(g_relay_info.description) - 1);
-    strncpy(g_relay_info.software, "https://github.com/teknari/c-relay", sizeof(g_relay_info.software) - 1);
-    strncpy(g_relay_info.version, "0.1.0", sizeof(g_relay_info.version) - 1);
+    // Load relay information from configuration system
+    const char* relay_name = get_config_value("relay_name");
+    if (relay_name) {
+        strncpy(g_relay_info.name, relay_name, sizeof(g_relay_info.name) - 1);
+    } else {
+        strncpy(g_relay_info.name, "C Nostr Relay", sizeof(g_relay_info.name) - 1);
+    }
+    
+    const char* relay_description = get_config_value("relay_description");
+    if (relay_description) {
+        strncpy(g_relay_info.description, relay_description, sizeof(g_relay_info.description) - 1);
+    } else {
+        strncpy(g_relay_info.description, "A high-performance Nostr relay implemented in C with SQLite storage", sizeof(g_relay_info.description) - 1);
+    }
+    
+    const char* relay_software = get_config_value("relay_software");
+    if (relay_software) {
+        strncpy(g_relay_info.software, relay_software, sizeof(g_relay_info.software) - 1);
+    } else {
+        strncpy(g_relay_info.software, "https://git.laantungir.net/laantungir/c-relay.git", sizeof(g_relay_info.software) - 1);
+    }
+    
+    const char* relay_version = get_config_value("relay_version");
+    if (relay_version) {
+        strncpy(g_relay_info.version, relay_version, sizeof(g_relay_info.version) - 1);
+    } else {
+        strncpy(g_relay_info.version, "0.2.0", sizeof(g_relay_info.version) - 1);
+    }
+    
+    // Load optional fields
+    const char* relay_contact = get_config_value("relay_contact");
+    if (relay_contact) {
+        strncpy(g_relay_info.contact, relay_contact, sizeof(g_relay_info.contact) - 1);
+    }
+    
+    const char* relay_pubkey = get_config_value("relay_pubkey");
+    if (relay_pubkey) {
+        strncpy(g_relay_info.pubkey, relay_pubkey, sizeof(g_relay_info.pubkey) - 1);
+    }
     
     // Initialize supported NIPs array
     g_relay_info.supported_nips = cJSON_CreateArray();
@@ -1268,24 +1336,25 @@ void init_relay_info() {
         cJSON_AddItemToArray(g_relay_info.supported_nips, cJSON_CreateNumber(13));  // NIP-13: Proof of Work
         cJSON_AddItemToArray(g_relay_info.supported_nips, cJSON_CreateNumber(15));  // NIP-15: EOSE
         cJSON_AddItemToArray(g_relay_info.supported_nips, cJSON_CreateNumber(20));  // NIP-20: Command results
+        cJSON_AddItemToArray(g_relay_info.supported_nips, cJSON_CreateNumber(40));  // NIP-40: Expiration Timestamp
     }
     
-    // Initialize server limitations
+    // Initialize server limitations using configuration
     g_relay_info.limitation = cJSON_CreateObject();
     if (g_relay_info.limitation) {
-        cJSON_AddNumberToObject(g_relay_info.limitation, "max_message_length", 16384);
-        cJSON_AddNumberToObject(g_relay_info.limitation, "max_subscriptions", MAX_SUBSCRIPTIONS_PER_CLIENT);
-        cJSON_AddNumberToObject(g_relay_info.limitation, "max_limit", 5000);
+        cJSON_AddNumberToObject(g_relay_info.limitation, "max_message_length", get_config_int("max_message_length", 16384));
+        cJSON_AddNumberToObject(g_relay_info.limitation, "max_subscriptions", get_config_int("max_subscriptions_per_client", 20));
+        cJSON_AddNumberToObject(g_relay_info.limitation, "max_limit", get_config_int("max_limit", 5000));
         cJSON_AddNumberToObject(g_relay_info.limitation, "max_subid_length", SUBSCRIPTION_ID_MAX_LENGTH);
-        cJSON_AddNumberToObject(g_relay_info.limitation, "max_event_tags", 100);
-        cJSON_AddNumberToObject(g_relay_info.limitation, "max_content_length", 8196);
+        cJSON_AddNumberToObject(g_relay_info.limitation, "max_event_tags", get_config_int("max_event_tags", 100));
+        cJSON_AddNumberToObject(g_relay_info.limitation, "max_content_length", get_config_int("max_content_length", 8196));
         cJSON_AddNumberToObject(g_relay_info.limitation, "min_pow_difficulty", g_pow_config.min_pow_difficulty);
-        cJSON_AddBoolToObject(g_relay_info.limitation, "auth_required", cJSON_False);
+        cJSON_AddBoolToObject(g_relay_info.limitation, "auth_required", get_config_bool("admin_enabled", 0) ? cJSON_True : cJSON_False);
         cJSON_AddBoolToObject(g_relay_info.limitation, "payment_required", cJSON_False);
         cJSON_AddBoolToObject(g_relay_info.limitation, "restricted_writes", cJSON_False);
         cJSON_AddNumberToObject(g_relay_info.limitation, "created_at_lower_limit", 0);
         cJSON_AddNumberToObject(g_relay_info.limitation, "created_at_upper_limit", 2147483647);
-        cJSON_AddNumberToObject(g_relay_info.limitation, "default_limit", 500);
+        cJSON_AddNumberToObject(g_relay_info.limitation, "default_limit", get_config_int("default_limit", 500));
     }
     
     // Initialize empty retention policies (can be configured later)
@@ -1598,48 +1667,39 @@ int handle_nip11_http_request(struct lws* wsi, const char* accept_header) {
 /////////////////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////////////////
 
-// Initialize PoW configuration with environment variables and defaults
+// Initialize PoW configuration using configuration system
 void init_pow_config() {
     log_info("Initializing NIP-13 Proof of Work configuration");
     
-    // Initialize with defaults (already set in struct initialization)
+    // Load PoW settings from configuration system
+    g_pow_config.enabled = get_config_bool("pow_enabled", 1);
+    g_pow_config.min_pow_difficulty = get_config_int("pow_min_difficulty", 0);
     
-    // Check environment variables for configuration
-    const char* pow_enabled_env = getenv("RELAY_POW_ENABLED");
-    if (pow_enabled_env) {
-        g_pow_config.enabled = (strcmp(pow_enabled_env, "1") == 0 ||
-                               strcmp(pow_enabled_env, "true") == 0 ||
-                               strcmp(pow_enabled_env, "yes") == 0);
-    }
-    
-    const char* min_diff_env = getenv("RELAY_MIN_POW_DIFFICULTY");
-    if (min_diff_env) {
-        int min_diff = atoi(min_diff_env);
-        if (min_diff >= 0 && min_diff <= 64) {  // Reasonable bounds
-            g_pow_config.min_pow_difficulty = min_diff;
-        }
-    }
-    
-    const char* pow_mode_env = getenv("RELAY_POW_MODE");
-    if (pow_mode_env) {
-        if (strcmp(pow_mode_env, "strict") == 0) {
+    // Get PoW mode from configuration
+    const char* pow_mode = get_config_value("pow_mode");
+    if (pow_mode) {
+        if (strcmp(pow_mode, "strict") == 0) {
             g_pow_config.validation_flags = NOSTR_POW_VALIDATE_ANTI_SPAM | NOSTR_POW_STRICT_FORMAT;
             g_pow_config.require_nonce_tag = 1;
             g_pow_config.reject_lower_targets = 1;
             g_pow_config.strict_format = 1;
             g_pow_config.anti_spam_mode = 1;
             log_info("PoW configured in strict anti-spam mode");
-        } else if (strcmp(pow_mode_env, "full") == 0) {
+        } else if (strcmp(pow_mode, "full") == 0) {
             g_pow_config.validation_flags = NOSTR_POW_VALIDATE_FULL;
             g_pow_config.require_nonce_tag = 1;
             log_info("PoW configured in full validation mode");
-        } else if (strcmp(pow_mode_env, "basic") == 0) {
+        } else if (strcmp(pow_mode, "basic") == 0) {
             g_pow_config.validation_flags = NOSTR_POW_VALIDATE_BASIC;
             log_info("PoW configured in basic validation mode");
-        } else if (strcmp(pow_mode_env, "disabled") == 0) {
+        } else if (strcmp(pow_mode, "disabled") == 0) {
             g_pow_config.enabled = 0;
-            log_info("PoW validation disabled via RELAY_POW_MODE");
+            log_info("PoW validation disabled via configuration");
         }
+    } else {
+        // Default to basic mode
+        g_pow_config.validation_flags = NOSTR_POW_VALIDATE_BASIC;
+        log_info("PoW configured in basic validation mode (default)");
     }
     
     // Log final configuration
@@ -1757,6 +1817,121 @@ int validate_event_pow(cJSON* event, char* error_message, size_t error_size) {
     return 0;  // Success
 }
 
+/////////////////////////////////////////////////////////////////////////////////////////
+/////////////////////////////////////////////////////////////////////////////////////////
+//             NIP-40 EXPIRATION TIMESTAMP HANDLING
+/////////////////////////////////////////////////////////////////////////////////////////
+/////////////////////////////////////////////////////////////////////////////////////////
+
+// Initialize expiration configuration using configuration system
+void init_expiration_config() {
+    log_info("Initializing NIP-40 Expiration Timestamp configuration");
+    
+    // Load expiration settings from configuration system
+    g_expiration_config.enabled = get_config_bool("expiration_enabled", 1);
+    g_expiration_config.strict_mode = get_config_bool("expiration_strict", 1);
+    g_expiration_config.filter_responses = get_config_bool("expiration_filter", 1);
+    g_expiration_config.delete_expired = get_config_bool("expiration_delete", 0);
+    g_expiration_config.grace_period = get_config_int("expiration_grace_period", 300);
+    
+    // Validate grace period bounds
+    if (g_expiration_config.grace_period < 0 || g_expiration_config.grace_period > 86400) {
+        log_warning("Invalid grace period, using default of 300 seconds");
+        g_expiration_config.grace_period = 300;
+    }
+    
+    // Log final configuration
+    char config_msg[512];
+    snprintf(config_msg, sizeof(config_msg),
+             "Expiration Configuration: enabled=%s, strict_mode=%s, filter_responses=%s, grace_period=%ld seconds",
+             g_expiration_config.enabled ? "true" : "false",
+             g_expiration_config.strict_mode ? "true" : "false",
+             g_expiration_config.filter_responses ? "true" : "false",
+             g_expiration_config.grace_period);
+    log_info(config_msg);
+}
+
+// Extract expiration timestamp from event tags
+long extract_expiration_timestamp(cJSON* tags) {
+    if (!tags || !cJSON_IsArray(tags)) {
+        return 0; // No expiration
+    }
+    
+    cJSON* tag = NULL;
+    cJSON_ArrayForEach(tag, tags) {
+        if (cJSON_IsArray(tag) && cJSON_GetArraySize(tag) >= 2) {
+            cJSON* tag_name = cJSON_GetArrayItem(tag, 0);
+            cJSON* tag_value = cJSON_GetArrayItem(tag, 1);
+            
+            if (cJSON_IsString(tag_name) && cJSON_IsString(tag_value)) {
+                const char* name = cJSON_GetStringValue(tag_name);
+                const char* value = cJSON_GetStringValue(tag_value);
+                
+                if (name && value && strcmp(name, "expiration") == 0) {
+                    long expiration_ts = atol(value);
+                    if (expiration_ts > 0) {
+                        return expiration_ts;
+                    }
+                }
+            }
+        }
+    }
+    
+    return 0; // No valid expiration tag found
+}
+
+// Check if event is currently expired
+int is_event_expired(cJSON* event, time_t current_time) {
+    if (!event) {
+        return 0; // Invalid event, not expired
+    }
+    
+    cJSON* tags = cJSON_GetObjectItem(event, "tags");
+    long expiration_ts = extract_expiration_timestamp(tags);
+    
+    if (expiration_ts == 0) {
+        return 0; // No expiration timestamp, not expired
+    }
+    
+    // Check if current time exceeds expiration + grace period
+    return (current_time > (expiration_ts + g_expiration_config.grace_period));
+}
+
+// Validate event expiration according to NIP-40
+int validate_event_expiration(cJSON* event, char* error_message, size_t error_size) {
+    if (!g_expiration_config.enabled) {
+        return 0; // Expiration validation disabled
+    }
+    
+    if (!event) {
+        snprintf(error_message, error_size, "expiration: null event");
+        return -1;
+    }
+    
+    // Check if event is expired
+    time_t current_time = time(NULL);
+    if (is_event_expired(event, current_time)) {
+        if (g_expiration_config.strict_mode) {
+            cJSON* tags = cJSON_GetObjectItem(event, "tags");
+            long expiration_ts = extract_expiration_timestamp(tags);
+            
+            snprintf(error_message, error_size,
+                    "invalid: event expired (expiration=%ld, current=%ld, grace=%ld)",
+                    expiration_ts, (long)current_time, g_expiration_config.grace_period);
+            log_warning("Event rejected: expired timestamp");
+            return -1;
+        } else {
+            // In non-strict mode, log but allow expired events
+            char debug_msg[256];
+            snprintf(debug_msg, sizeof(debug_msg),
+                    "Accepting expired event (strict_mode disabled)");
+            log_info(debug_msg);
+        }
+    }
+    
+    return 0; // Success
+}
+
 /////////////////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////////////////
 //             DATABASE FUNCTIONS
@@ -1765,13 +1940,21 @@ int validate_event_pow(cJSON* event, char* error_message, size_t error_size) {
 
 // Initialize database connection
 int init_database() {
-    int rc = sqlite3_open(DATABASE_PATH, &g_db);
+    // Use configurable database path, falling back to default
+    const char* db_path = get_config_value("database_path");
+    if (!db_path) {
+        db_path = DEFAULT_DATABASE_PATH;
+    }
+    
+    int rc = sqlite3_open(db_path, &g_db);
     if (rc != SQLITE_OK) {
         log_error("Cannot open database");
         return -1;
     }
     
-    log_success("Database connection established");
+    char success_msg[256];
+    snprintf(success_msg, sizeof(success_msg), "Database connection established: %s", db_path);
+    log_success(success_msg);
     return 0;
 }
 
@@ -2082,7 +2265,7 @@ int handle_req_message(const char* sub_id, cJSON* filters, struct lws *wsi, stru
     }
     
     // Check session subscription limits
-    if (pss && pss->subscription_count >= MAX_SUBSCRIPTIONS_PER_CLIENT) {
+    if (pss && pss->subscription_count >= g_subscription_manager.max_subscriptions_per_client) {
         log_error("Maximum subscriptions per client exceeded");
         
         // Send CLOSED notice
@@ -2165,6 +2348,9 @@ int handle_req_message(const char* sub_id, cJSON* filters, struct lws *wsi, stru
         char* sql_ptr = sql + strlen(sql);
         int remaining = sizeof(sql) - strlen(sql);
         
+        // Note: Expiration filtering will be done at application level
+        // after retrieving events to ensure compatibility with all SQLite versions
+        
         // Handle kinds filter
         cJSON* kinds = cJSON_GetObjectItem(filter, "kinds");
         if (kinds && cJSON_IsArray(kinds)) {
@@ -2293,6 +2479,16 @@ int handle_req_message(const char* sub_id, cJSON* filters, struct lws *wsi, stru
             }
             cJSON_AddItemToObject(event, "tags", tags);
             
+            // Check expiration filtering (NIP-40) at application level
+            if (g_expiration_config.enabled && g_expiration_config.filter_responses) {
+                time_t current_time = time(NULL);
+                if (is_event_expired(event, current_time)) {
+                    // Skip this expired event
+                    cJSON_Delete(event);
+                    continue;
+                }
+            }
+            
             // Send EVENT message
             cJSON* event_msg = cJSON_CreateArray();
             cJSON_AddItemToArray(event_msg, cJSON_CreateString("EVENT"));
@@ -2388,14 +2584,20 @@ int handle_event_message(cJSON* event, char* error_message, size_t error_size) {
         return pow_result;  // PoW validation failed, error message already set
     }
     
-    // Step 4: Complete event validation (combines structure + signature + additional checks)
+    // Step 4: Validate expiration timestamp (NIP-40) if enabled
+    int expiration_result = validate_event_expiration(event, error_message, error_size);
+    if (expiration_result != 0) {
+        return expiration_result;  // Expiration validation failed, error message already set
+    }
+    
+    // Step 5: Complete event validation (combines structure + signature + additional checks)
     int validation_result = nostr_validate_event(event);
     if (validation_result != NOSTR_SUCCESS) {
         snprintf(error_message, error_size, "invalid: complete event validation failed");
         return validation_result;
     }
     
-    // Step 5: Check for special event types and handle accordingly
+    // Step 6: Check for special event types and handle accordingly
     cJSON* kind_obj = cJSON_GetObjectItem(event, "kind");
     cJSON* pubkey_obj = cJSON_GetObjectItem(event, "pubkey");
     cJSON* created_at_obj = cJSON_GetObjectItem(event, "created_at");
@@ -2435,7 +2637,7 @@ int handle_event_message(cJSON* event, char* error_message, size_t error_size) {
         }
     }
     
-    // Step 6: Store event in database
+    // Step 7: Store event in database
     if (store_event(event) == 0) {
         error_message[0] = '\0';  // Success - empty error message
         log_success("Event validated and stored successfully");
@@ -2687,7 +2889,7 @@ int start_websocket_relay() {
     log_info("Starting libwebsockets-based Nostr relay server...");
 
     memset(&info, 0, sizeof(info));
-    info.port = DEFAULT_PORT;
+    info.port = get_config_int("relay_port", DEFAULT_PORT);
     info.protocols = protocols;
     info.gid = -1;
     info.uid = -1;
@@ -2713,7 +2915,9 @@ int start_websocket_relay() {
         return -1;
     }
 
-    log_success("WebSocket relay started on ws://127.0.0.1:8888");
+    char startup_msg[256];
+    snprintf(startup_msg, sizeof(startup_msg), "WebSocket relay started on ws://127.0.0.1:%d", info.port);
+    log_success(startup_msg);
 
     // Main event loop with proper signal handling
     while (g_server_running) {
@@ -2769,6 +2973,12 @@ int main(int argc, char* argv[]) {
                     log_error("Invalid port number");
                     return 1;
                 }
+                // Store port in configuration system
+                char port_str[16];
+                snprintf(port_str, sizeof(port_str), "%d", port);
+                set_database_config("relay_port", port_str, "command_line");
+                // Re-apply configuration to make sure global variables are updated
+                apply_configuration_to_globals();
             } else {
                 log_error("Port argument requires a value");
                 return 1;
@@ -2786,25 +2996,40 @@ int main(int argc, char* argv[]) {
     
     printf(BLUE BOLD "=== C Nostr Relay Server ===" RESET "\n");
     
-    // Initialize database
+    // Initialize database FIRST (required for configuration system)
     if (init_database() != 0) {
         log_error("Failed to initialize database");
         return 1;
     }
     
-    // Initialize nostr library
+    // Initialize nostr library BEFORE configuration system
+    // (required for Nostr event generation in config files)
     if (nostr_init() != 0) {
         log_error("Failed to initialize nostr library");
         close_database();
         return 1;
     }
     
+    // Initialize configuration system (loads file + database + applies to globals)
+    if (init_configuration_system() != 0) {
+        log_error("Failed to initialize configuration system");
+        nostr_cleanup();
+        close_database();
+        return 1;
+    }
+    
     // Initialize NIP-11 relay information
     init_relay_info();
     
     // Initialize NIP-13 PoW configuration
     init_pow_config();
     
+    // Initialize NIP-40 expiration configuration
+    init_expiration_config();
+    
+    // Update subscription manager configuration
+    update_subscription_manager_config();
+    
     log_info("Starting relay server...");
     
     // Start WebSocket Nostr relay server
@@ -2812,6 +3037,7 @@ int main(int argc, char* argv[]) {
     
     // Cleanup
     cleanup_relay_info();
+    cleanup_configuration_system();
     nostr_cleanup();
     close_database();
     

tests/40_nip_test.sh

@@ -0,0 +1,539 @@
+#!/bin/bash
+
+# NIP-40 Expiration Timestamp Test Suite for C Nostr Relay
+# Tests expiration timestamp handling in the relay's event processing pipeline
+
+set -e  # Exit on error
+
+# Color constants
+RED='\033[31m'
+GREEN='\033[32m'
+YELLOW='\033[33m'
+BLUE='\033[34m'
+BOLD='\033[1m'
+RESET='\033[0m'
+
+# Test configuration
+RELAY_URL="ws://127.0.0.1:8888"
+HTTP_URL="http://127.0.0.1:8888"
+TEST_COUNT=0
+PASSED_COUNT=0
+FAILED_COUNT=0
+
+# Test results tracking
+declare -a TEST_RESULTS=()
+
+print_info() {
+    echo -e "${BLUE}[INFO]${RESET} $1"
+}
+
+print_success() {
+    echo -e "${GREEN}${BOLD}[SUCCESS]${RESET} $1"
+}
+
+print_warning() {
+    echo -e "${YELLOW}[WARNING]${RESET} $1"
+}
+
+print_error() {
+    echo -e "${RED}${BOLD}[ERROR]${RESET} $1"
+}
+
+print_test_header() {
+    TEST_COUNT=$((TEST_COUNT + 1))
+    echo ""
+    echo -e "${BOLD}=== TEST $TEST_COUNT: $1 ===${RESET}"
+}
+
+record_test_result() {
+    local test_name="$1"
+    local result="$2"
+    local details="$3"
+    
+    TEST_RESULTS+=("$test_name|$result|$details")
+    
+    if [ "$result" = "PASS" ]; then
+        PASSED_COUNT=$((PASSED_COUNT + 1))
+        print_success "PASS: $test_name"
+    else
+        FAILED_COUNT=$((FAILED_COUNT + 1))
+        print_error "FAIL: $test_name"
+        if [ -n "$details" ]; then
+            echo "       Details: $details"
+        fi
+    fi
+}
+
+# Check if relay is running
+check_relay_running() {
+    print_info "Checking if relay is running..."
+    
+    if ! curl -s -H "Accept: application/nostr+json" "$HTTP_URL/" >/dev/null 2>&1; then
+        print_error "Relay is not running or not accessible at $HTTP_URL"
+        print_info "Please start the relay with: ./make_and_restart_relay.sh"
+        exit 1
+    fi
+    
+    print_success "Relay is running and accessible"
+}
+
+# Test NIP-11 relay information includes NIP-40
+test_nip11_expiration_support() {
+    print_test_header "NIP-11 Expiration Support Advertisement"
+    
+    print_info "Fetching relay information..."
+    RELAY_INFO=$(curl -s -H "Accept: application/nostr+json" "$HTTP_URL/")
+    
+    echo "Relay Info Response:"
+    echo "$RELAY_INFO" | jq '.'
+    echo ""
+    
+    # Check if NIP-40 is in supported_nips
+    if echo "$RELAY_INFO" | jq -e '.supported_nips | index(40)' >/dev/null 2>&1; then
+        print_success "✓ NIP-40 found in supported_nips array"
+        NIP40_SUPPORTED=true
+    else
+        print_error "✗ NIP-40 not found in supported_nips array"
+        NIP40_SUPPORTED=false
+    fi
+    
+    if [ "$NIP40_SUPPORTED" = true ]; then
+        record_test_result "NIP-11 Expiration Support Advertisement" "PASS" "NIP-40 advertised in relay info"
+        return 0
+    else
+        record_test_result "NIP-11 Expiration Support Advertisement" "FAIL" "NIP-40 not advertised"
+        return 1
+    fi
+}
+
+# Helper function to create event with expiration tag
+create_event_with_expiration() {
+    local content="$1"
+    local expiration_timestamp="$2"
+    local private_key="91ba716fa9e7ea2fcbad360cf4f8e0d312f73984da63d90f524ad61a6a1e7dbe"
+    
+    if ! command -v nak &> /dev/null; then
+        echo ""
+        return 1
+    fi
+    
+    # Create event with expiration tag
+    nak event --sec "$private_key" -c "$content" -t "expiration=$expiration_timestamp" --ts $(date +%s)
+}
+
+# Helper function to send event and check response
+send_event_and_check() {
+    local event_json="$1"
+    local expected_result="$2"  # "accept" or "reject"
+    local description="$3"
+    
+    if [ -z "$event_json" ]; then
+        return 1
+    fi
+    
+    # Create EVENT message
+    local event_message="[\"EVENT\",$event_json]"
+    
+    # Send to relay
+    if command -v websocat &> /dev/null; then
+        local response=$(echo "$event_message" | timeout 5s websocat "$RELAY_URL" 2>&1 || echo "Connection failed")
+        
+        print_info "Relay response: $response"
+        
+        if [[ "$response" == *"Connection failed"* ]]; then
+            print_error "✗ Failed to connect to relay"
+            return 1
+        elif [[ "$expected_result" == "accept" && "$response" == *"true"* ]]; then
+            print_success "✓ $description accepted as expected"
+            return 0
+        elif [[ "$expected_result" == "reject" && "$response" == *"false"* ]]; then
+            print_success "✓ $description rejected as expected"
+            return 0
+        elif [[ "$expected_result" == "accept" && "$response" == *"false"* ]]; then
+            print_error "✗ $description unexpectedly rejected: $response"
+            return 1
+        elif [[ "$expected_result" == "reject" && "$response" == *"true"* ]]; then
+            print_error "✗ $description unexpectedly accepted: $response"
+            return 1
+        else
+            print_warning "? Unclear response for $description: $response"
+            return 1
+        fi
+    else
+        print_error "websocat not found - required for testing"
+        return 1
+    fi
+}
+
+# Test event without expiration tag
+test_event_without_expiration() {
+    print_test_header "Event Submission Without Expiration Tag"
+    
+    if ! command -v nak &> /dev/null; then
+        print_warning "nak command not found - skipping expiration tests"
+        record_test_result "Event Submission Without Expiration Tag" "SKIP" "nak not available"
+        return 0
+    fi
+    
+    print_info "Creating event without expiration tag..."
+    
+    local private_key="91ba716fa9e7ea2fcbad360cf4f8e0d312f73984da63d90f524ad61a6a1e7dbe"
+    local event_json=$(nak event --sec "$private_key" -c "Test event without expiration" --ts $(date +%s))
+    
+    print_info "Generated event:"
+    echo "$event_json" | jq '.'
+    echo ""
+    
+    if send_event_and_check "$event_json" "accept" "Event without expiration tag"; then
+        record_test_result "Event Submission Without Expiration Tag" "PASS" "Non-expiring event accepted"
+        return 0
+    else
+        record_test_result "Event Submission Without Expiration Tag" "FAIL" "Non-expiring event handling failed"
+        return 1
+    fi
+}
+
+# Test event with future expiration (should be accepted)
+test_event_with_future_expiration() {
+    print_test_header "Event Submission With Future Expiration"
+    
+    if ! command -v nak &> /dev/null; then
+        record_test_result "Event Submission With Future Expiration" "SKIP" "nak not available"
+        return 0
+    fi
+    
+    print_info "Creating event with future expiration (1 hour from now)..."
+    
+    local future_timestamp=$(($(date +%s) + 3600))  # 1 hour from now
+    local event_json=$(create_event_with_expiration "Test event expiring in 1 hour" "$future_timestamp")
+    
+    if [ -z "$event_json" ]; then
+        record_test_result "Event Submission With Future Expiration" "FAIL" "Failed to create event"
+        return 1
+    fi
+    
+    print_info "Generated event (expires at $future_timestamp):"
+    echo "$event_json" | jq '.'
+    echo ""
+    
+    if send_event_and_check "$event_json" "accept" "Event with future expiration"; then
+        record_test_result "Event Submission With Future Expiration" "PASS" "Future-expiring event accepted"
+        return 0
+    else
+        record_test_result "Event Submission With Future Expiration" "FAIL" "Future-expiring event rejected"
+        return 1
+    fi
+}
+
+# Test event with past expiration (should be rejected in strict mode)
+test_event_with_past_expiration() {
+    print_test_header "Event Submission With Past Expiration"
+    
+    if ! command -v nak &> /dev/null; then
+        record_test_result "Event Submission With Past Expiration" "SKIP" "nak not available"
+        return 0
+    fi
+    
+    print_info "Creating event with past expiration (1 hour ago)..."
+    
+    local past_timestamp=$(($(date +%s) - 3600))  # 1 hour ago
+    local event_json=$(create_event_with_expiration "Test event expired 1 hour ago" "$past_timestamp")
+    
+    if [ -z "$event_json" ]; then
+        record_test_result "Event Submission With Past Expiration" "FAIL" "Failed to create event"
+        return 1
+    fi
+    
+    print_info "Generated event (expired at $past_timestamp):"
+    echo "$event_json" | jq '.'
+    echo ""
+    
+    # In strict mode (default), this should be rejected
+    if send_event_and_check "$event_json" "reject" "Event with past expiration"; then
+        record_test_result "Event Submission With Past Expiration" "PASS" "Expired event correctly rejected in strict mode"
+        return 0
+    else
+        record_test_result "Event Submission With Past Expiration" "FAIL" "Expired event handling failed"
+        return 1
+    fi
+}
+
+# Test event with expiration within grace period
+test_event_within_grace_period() {
+    print_test_header "Event Submission Within Grace Period"
+    
+    if ! command -v nak &> /dev/null; then
+        record_test_result "Event Submission Within Grace Period" "SKIP" "nak not available"
+        return 0
+    fi
+    
+    print_info "Creating event with expiration within grace period (2 minutes ago, grace period is 5 minutes)..."
+    
+    local grace_timestamp=$(($(date +%s) - 120))  # 2 minutes ago (within 5 minute grace period)
+    local event_json=$(create_event_with_expiration "Test event within grace period" "$grace_timestamp")
+    
+    if [ -z "$event_json" ]; then
+        record_test_result "Event Submission Within Grace Period" "FAIL" "Failed to create event"
+        return 1
+    fi
+    
+    print_info "Generated event (expired at $grace_timestamp, within grace period):"
+    echo "$event_json" | jq '.'
+    echo ""
+    
+    # Should be accepted due to grace period
+    if send_event_and_check "$event_json" "accept" "Event within grace period"; then
+        record_test_result "Event Submission Within Grace Period" "PASS" "Event within grace period accepted"
+        return 0
+    else
+        record_test_result "Event Submission Within Grace Period" "FAIL" "Grace period handling failed"
+        return 1
+    fi
+}
+
+# Test event filtering in subscriptions
+test_expiration_filtering_in_subscriptions() {
+    print_test_header "Expiration Filtering in Subscriptions"
+    
+    if ! command -v nak &> /dev/null || ! command -v websocat &> /dev/null; then
+        record_test_result "Expiration Filtering in Subscriptions" "SKIP" "Required tools not available"
+        return 0
+    fi
+    
+    print_info "Setting up test events for subscription filtering..."
+    
+    # First, create a few events with different expiration times
+    local private_key="91ba716fa9e7ea2fcbad360cf4f8e0d312f73984da63d90f524ad61a6a1e7dbe"
+    
+    # Event 1: No expiration (should be returned)
+    local event1=$(nak event --sec "$private_key" -c "Event without expiration for filtering test" --ts $(date +%s))
+    
+    # Event 2: Future expiration (should be returned)
+    local future_timestamp=$(($(date +%s) + 1800))  # 30 minutes from now
+    local event2=$(create_event_with_expiration "Event with future expiration for filtering test" "$future_timestamp")
+    
+    # Event 3: Past expiration (should NOT be returned if filtering is enabled)
+    local past_timestamp=$(($(date +%s) - 3600))  # 1 hour ago
+    local event3=$(create_event_with_expiration "Event with past expiration for filtering test" "$past_timestamp")
+    
+    print_info "Publishing test events..."
+    
+    # Note: We expect event3 to be rejected on submission in strict mode,
+    # so we'll create it with a slightly more recent expiration that might get through
+    local recent_past=$(($(date +%s) - 600))  # 10 minutes ago (outside grace period)
+    local event3_recent=$(create_event_with_expiration "Recently expired event for filtering test" "$recent_past")
+    
+    # Try to submit all events (some may be rejected)
+    echo "[\"EVENT\",$event1]" | timeout 3s websocat "$RELAY_URL" >/dev/null 2>&1 || true
+    echo "[\"EVENT\",$event2]" | timeout 3s websocat "$RELAY_URL" >/dev/null 2>&1 || true
+    echo "[\"EVENT\",$event3_recent]" | timeout 3s websocat "$RELAY_URL" >/dev/null 2>&1 || true
+    
+    sleep 2  # Let events settle
+    
+    print_info "Testing subscription filtering..."
+    
+    # Create subscription for recent events
+    local req_message='["REQ","filter_test",{"kinds":[1],"limit":10}]'
+    local response=$(echo -e "$req_message\n[\"CLOSE\",\"filter_test\"]" | timeout 5s websocat "$RELAY_URL" 2>/dev/null || echo "")
+    
+    print_info "Subscription response:"
+    echo "$response"
+    echo ""
+    
+    # Count events that contain our test content
+    local no_exp_count=0
+    local future_exp_count=0  
+    local past_exp_count=0
+    
+    if echo "$response" | grep -q "Event without expiration for filtering test"; then
+        no_exp_count=1
+        print_success "✓ Event without expiration found in subscription results"
+    fi
+    
+    if echo "$response" | grep -q "Event with future expiration for filtering test"; then
+        future_exp_count=1
+        print_success "✓ Event with future expiration found in subscription results"
+    fi
+    
+    if echo "$response" | grep -q "Recently expired event for filtering test"; then
+        past_exp_count=1
+        print_warning "✗ Recently expired event found in subscription results (should be filtered)"
+    else
+        print_success "✓ Recently expired event properly filtered from subscription results"
+    fi
+    
+    # Evaluate results
+    local expected_events=$((no_exp_count + future_exp_count))
+    if [ $expected_events -ge 1 ] && [ $past_exp_count -eq 0 ]; then
+        record_test_result "Expiration Filtering in Subscriptions" "PASS" "Expired events properly filtered from subscriptions"
+        return 0
+    else
+        record_test_result "Expiration Filtering in Subscriptions" "FAIL" "Expiration filtering not working properly in subscriptions"
+        return 1
+    fi
+}
+
+# Test malformed expiration tags
+test_malformed_expiration_tags() {
+    print_test_header "Handling of Malformed Expiration Tags"
+    
+    if ! command -v nak &> /dev/null; then
+        record_test_result "Handling of Malformed Expiration Tags" "SKIP" "nak not available"
+        return 0
+    fi
+    
+    print_info "Testing events with malformed expiration tags..."
+    
+    local private_key="91ba716fa9e7ea2fcbad360cf4f8e0d312f73984da63d90f524ad61a6a1e7dbe"
+    
+    # Test 1: Non-numeric expiration value
+    local event1=$(nak event --sec "$private_key" -c "Event with non-numeric expiration" -t "expiration=not_a_number" --ts $(date +%s))
+    
+    # Test 2: Empty expiration value  
+    local event2=$(nak event --sec "$private_key" -c "Event with empty expiration" -t "expiration=" --ts $(date +%s))
+    
+    print_info "Testing non-numeric expiration value..."
+    if send_event_and_check "$event1" "accept" "Event with non-numeric expiration (should be treated as no expiration)"; then
+        print_success "✓ Non-numeric expiration handled gracefully"
+        malformed_test1=true
+    else
+        malformed_test1=false
+    fi
+    
+    print_info "Testing empty expiration value..."
+    if send_event_and_check "$event2" "accept" "Event with empty expiration (should be treated as no expiration)"; then
+        print_success "✓ Empty expiration handled gracefully"
+        malformed_test2=true
+    else
+        malformed_test2=false
+    fi
+    
+    if [ "$malformed_test1" = true ] && [ "$malformed_test2" = true ]; then
+        record_test_result "Handling of Malformed Expiration Tags" "PASS" "Malformed expiration tags handled gracefully"
+        return 0
+    else
+        record_test_result "Handling of Malformed Expiration Tags" "FAIL" "Malformed expiration tag handling failed"
+        return 1
+    fi
+}
+
+# Test configuration via environment variables
+test_expiration_configuration() {
+    print_test_header "Expiration Configuration Via Environment Variables"
+    
+    print_info "Testing expiration configuration from relay logs..."
+    
+    if [ -f "relay.log" ]; then
+        print_info "Current configuration from logs:"
+        grep "Expiration Configuration:" relay.log | tail -1 || print_warning "No expiration configuration found in logs"
+    else
+        print_warning "No relay.log found"
+    fi
+    
+    # The relay should be running with default configuration
+    print_info "Default configuration should be:"
+    print_info "  enabled=true"
+    print_info "  strict_mode=true (rejects expired events on submission)"
+    print_info "  filter_responses=true (filters expired events from responses)"
+    print_info "  grace_period=300 seconds (5 minutes)"
+    
+    # Test current behavior matches expected default configuration
+    print_info "Configuration test based on observed behavior:"
+    
+    # Check if NIP-40 is advertised (indicates enabled=true)
+    if curl -s -H "Accept: application/nostr+json" "$HTTP_URL/" | jq -e '.supported_nips | index(40)' >/dev/null 2>&1; then
+        print_success "✓ NIP-40 support advertised (enabled=true)"
+        config_test=true
+    else
+        print_error "✗ NIP-40 not advertised (may be disabled)"
+        config_test=false
+    fi
+    
+    if [ "$config_test" = true ]; then
+        record_test_result "Expiration Configuration Via Environment Variables" "PASS" "Expiration configuration is accessible and working"
+        return 0
+    else
+        record_test_result "Expiration Configuration Via Environment Variables" "FAIL" "Expiration configuration issues detected"
+        return 1
+    fi
+}
+
+# Print test summary
+print_test_summary() {
+    echo ""
+    echo -e "${BOLD}=== TEST SUMMARY ===${RESET}"
+    echo "Total tests run: $TEST_COUNT"
+    echo -e "${GREEN}Passed: $PASSED_COUNT${RESET}"
+    echo -e "${RED}Failed: $FAILED_COUNT${RESET}"
+    
+    if [ $FAILED_COUNT -gt 0 ]; then
+        echo ""
+        echo -e "${RED}${BOLD}Failed tests:${RESET}"
+        for result in "${TEST_RESULTS[@]}"; do
+            IFS='|' read -r name status details <<< "$result"
+            if [ "$status" = "FAIL" ]; then
+                echo -e "  ${RED}✗ $name${RESET}"
+                if [ -n "$details" ]; then
+                    echo "    $details"
+                fi
+            fi
+        done
+    fi
+    
+    echo ""
+    if [ $FAILED_COUNT -eq 0 ]; then
+        echo -e "${GREEN}${BOLD}🎉 ALL TESTS PASSED!${RESET}"
+        echo -e "${GREEN}✅ NIP-40 Expiration Timestamp support is working correctly in the relay${RESET}"
+        return 0
+    else
+        echo -e "${RED}${BOLD}❌ SOME TESTS FAILED${RESET}"
+        echo "Please review the output above and check relay logs for more details."
+        return 1
+    fi
+}
+
+# Main test execution
+main() {
+    echo -e "${BOLD}=== NIP-40 Expiration Timestamp Relay Test Suite ===${RESET}"
+    echo "Testing NIP-40 Expiration Timestamp support in the C Nostr Relay"
+    echo "Relay URL: $RELAY_URL"
+    echo ""
+    
+    # Check prerequisites
+    if ! command -v curl &> /dev/null; then
+        print_error "curl is required but not installed"
+        exit 1
+    fi
+    
+    if ! command -v jq &> /dev/null; then
+        print_error "jq is required but not installed"
+        exit 1
+    fi
+    
+    if ! command -v websocat &> /dev/null; then
+        print_warning "websocat not found - WebSocket tests will be skipped"
+    fi
+    
+    if ! command -v nak &> /dev/null; then
+        print_warning "nak not found - Event generation tests will be skipped"
+        print_info "Install with: go install github.com/fiatjaf/nak@latest"
+    fi
+    
+    # Run tests
+    check_relay_running
+    test_nip11_expiration_support
+    test_event_without_expiration
+    test_event_with_future_expiration
+    test_event_with_past_expiration
+    test_event_within_grace_period
+    test_expiration_filtering_in_subscriptions
+    test_malformed_expiration_tags
+    test_expiration_configuration
+    
+    # Print summary
+    print_test_summary
+    exit $?
+}
+
+# Run main function
+main "$@"