💎 Hash Cron Directive in TuskLang for Ruby

Ruby Documentation

Hash Cron Directive in TuskLang for Ruby

Welcome to the automated revolution with TuskLang's Hash Cron Directive! This is where we break free from the constraints of traditional cron systems and embrace the power of declarative, configuration-driven task scheduling. In Ruby, this means combining TuskLang's elegant hash directives with Ruby's powerful scheduling capabilities to create automated systems that are as expressive as they are powerful.

What is the Hash Cron Directive?

The Hash Cron Directive (#cron) is TuskLang's declaration of independence from traditional cron systems. It allows you to define complete scheduled tasks, jobs, and automated workflows using simple hash configurations. In Ruby, this translates to powerful, declarative scheduling definitions that can be processed, validated, and executed with minimal ceremony.

Basic Cron Directive Syntax

Basic cron job definition

cron_job_config = { "#cron" => { "name" => "data-backup", "schedule" => "0 2 *", "handler" => "BackupJob#execute", "timezone" => "UTC", "enabled" => true, "description" => "Daily database backup at 2 AM" } }

Ruby class to process the cron directive

class CronDirectiveProcessor def initialize(config) @config = config @tusk_config = load_tusk_config end

def process_cron_directive cron_config = @config["#cron"] return nil unless cron_config

{ name: cron_config["name"], schedule: cron_config["schedule"], handler: parse_handler(cron_config["handler"]), timezone: cron_config["timezone"] || "UTC", enabled: cron_config["enabled"] || true, description: cron_config["description"], retry_policy: process_retry_policy(cron_config["retry_policy"]), timeout: cron_config["timeout"] || 300 } end

private

def parse_handler(handler_string) return nil unless handler_string job_class, method = handler_string.split("#") { class: job_class, method: method } end

def process_retry_policy(retry_config) return {} unless retry_config

{ max_attempts: retry_config["max_attempts"] || 3, backoff: retry_config["backoff"] || "exponential", delay: retry_config["delay"] || 60 } end

def load_tusk_config TuskConfig.load("peanu.tsk") end end

Advanced Cron Configuration

Comprehensive cron job configuration

advanced_cron_config = { "#cron" => { "jobs" => { "data-backup" => { "schedule" => "0 2 *", "handler" => "BackupJob#execute", "timezone" => "UTC", "enabled" => true, "description" => "Daily database backup", "retry_policy" => { "max_attempts" => 3, "backoff" => "exponential", "delay" => 300 }, "timeout" => 1800, "dependencies" => ["database-maintenance"], "notifications" => { "on_success" => ["email:admin@example.com"], "on_failure" => ["email:admin@example.com", "slack:alerts"] } }, "report-generation" => { "schedule" => "0 6 1", "handler" => "ReportJob#generate_weekly", "timezone" => "America/New_York", "enabled" => true, "description" => "Weekly report generation", "parameters" => { "report_type" => "weekly", "format" => "pdf", "recipients" => "@management_team" }, "timeout" => 3600, "resources" => { "memory" => "2GB", "cpu" => "high" } }, "cache-cleanup" => { "schedule" => "/30 *", "handler" => "CacheJob#cleanup", "enabled" => true, "description" => "Cache cleanup every 30 minutes", "timeout" => 300, "priority" => "low" } }, "schedules" => { "business-hours" => { "timezone" => "America/New_York", "start_time" => "09:00", "end_time" => "17:00", "days" => ["monday", "tuesday", "wednesday", "thursday", "friday"] }, "maintenance-window" => { "timezone" => "UTC", "start_time" => "02:00", "end_time" => "04:00", "days" => ["sunday"] } }, "notifications" => { "email" => { "smtp" => { "host" => "@smtp_host", "port" => "@smtp_port", "username" => "@smtp_username", "password" => "@smtp_password" }, "from" => "cron@example.com", "templates" => { "success" => "notifications/success.html.erb", "failure" => "notifications/failure.html.erb" } }, "slack" => { "webhook_url" => "@slack_webhook", "channel" => "#alerts", "username" => "CronBot" } } } }

Ruby processor for advanced cron configurations

class AdvancedCronProcessor < CronDirectiveProcessor def process_advanced_config cron_config = @config["#cron"] { jobs: process_jobs(cron_config["jobs"]), schedules: process_schedules(cron_config["schedules"]), notifications: process_notifications(cron_config["notifications"]), global_settings: process_global_settings(cron_config["global_settings"]) } end

private

def process_jobs(jobs_config) jobs_config.transform_values do |job_config| { schedule: job_config["schedule"], handler: parse_handler(job_config["handler"]), timezone: job_config["timezone"] || "UTC", enabled: job_config["enabled"] || true, description: job_config["description"], retry_policy: process_retry_policy(job_config["retry_policy"]), timeout: job_config["timeout"] || 300, dependencies: Array(job_config["dependencies"]), notifications: process_job_notifications(job_config["notifications"]), parameters: job_config["parameters"] || {}, resources: job_config["resources"] || {}, priority: job_config["priority"] || "normal" } end end

def process_schedules(schedules_config) return {} unless schedules_config

schedules_config.transform_values do |schedule_config| { timezone: schedule_config["timezone"] || "UTC", start_time: schedule_config["start_time"], end_time: schedule_config["end_time"], days: Array(schedule_config["days"]), exceptions: schedule_config["exceptions"] || [] } end end

def process_notifications(notifications_config) return {} unless notifications_config

{ email: process_email_notifications(notifications_config["email"]), slack: process_slack_notifications(notifications_config["slack"]), webhook: process_webhook_notifications(notifications_config["webhook"]) } end

def process_job_notifications(notifications_config) return {} unless notifications_config

{ on_success: Array(notifications_config["on_success"]), on_failure: Array(notifications_config["on_failure"]), on_timeout: Array(notifications_config["on_timeout"]) } end

def process_email_notifications(email_config) return {} unless email_config

{ smtp: process_smtp_config(email_config["smtp"]), from: email_config["from"], templates: email_config["templates"] || {} } end

def process_smtp_config(smtp_config) return {} unless smtp_config

{ host: resolve_tusk_variable(smtp_config["host"]), port: resolve_tusk_variable(smtp_config["port"]), username: resolve_tusk_variable(smtp_config["username"]), password: resolve_tusk_variable(smtp_config["password"]), ssl: smtp_config["ssl"] || true } end

def process_slack_notifications(slack_config) return {} unless slack_config

{ webhook_url: resolve_tusk_variable(slack_config["webhook_url"]), channel: slack_config["channel"], username: slack_config["username"] } end

def process_webhook_notifications(webhook_config) return {} unless webhook_config

{ url: resolve_tusk_variable(webhook_config["url"]), method: webhook_config["method"] || "POST", headers: webhook_config["headers"] || {} } end

def process_global_settings(global_config) return {} unless global_config

{ max_concurrent_jobs: global_config["max_concurrent_jobs"] || 10, job_queue: global_config["job_queue"] || "default", log_level: global_config["log_level"] || "info", metrics: global_config["metrics"] || false } end

def resolve_tusk_variable(variable) return variable unless variable&.start_with?("@") variable_name = variable[1..-1] TuskConfig.get(variable_name) end end

Job Execution and Scheduling

Job execution configuration with TuskLang features

job_execution_config = { "#cron" => { "jobs" => { "data-processing" => { "schedule" => "/15 *", "handler" => "DataProcessingJob#execute", "parameters" => { "batch_size" => "@batch_size", "source" => "@data_source", "destination" => "@data_destination" }, "validation" => { "check_dependencies" => true, "validate_parameters" => true, "check_resources" => true }, "monitoring" => { "track_performance" => true, "alert_threshold" => 300, "metrics" => ["execution_time", "memory_usage", "records_processed"] } } } } }

Ruby job execution processor

class JobExecutionProcessor def initialize(config) @config = config["#cron"] @scheduler = Rufus::Scheduler.new end

def schedule_jobs @config["jobs"].each do |job_name, job_config| next unless job_config["enabled"]

schedule_job(job_name, job_config) end end

def execute_job(job_name, job_config, context = {}) # Validate job before execution validation_result = validate_job(job_name, job_config, context) return validation_result unless validation_result[:valid]

# Check dependencies dependency_result = check_dependencies(job_config["dependencies"]) return dependency_result unless dependency_result[:satisfied]

# Execute job with monitoring start_time = Time.current result = execute_job_handler(job_config["handler"], job_config["parameters"], context) end_time = Time.current

# Record metrics record_metrics(job_name, start_time, end_time, result)

# Send notifications send_notifications(job_name, job_config, result)

result end

private

def schedule_job(job_name, job_config) schedule = job_config["schedule"] timezone = job_config["timezone"] || "UTC" @scheduler.cron(schedule, tz: timezone) do execute_job(job_name, job_config) end end

def validate_job(job_name, job_config, context) validation_config = job_config["validation"] return { valid: true } unless validation_config

if validation_config["check_dependencies"] dependency_result = check_dependencies(job_config["dependencies"]) return dependency_result unless dependency_result[:satisfied] end

if validation_config["validate_parameters"] parameter_result = validate_parameters(job_config["parameters"]) return parameter_result unless parameter_result[:valid] end

if validation_config["check_resources"] resource_result = check_resources(job_config["resources"]) return resource_result unless resource_result[:available] end

{ valid: true } end

def check_dependencies(dependencies) return { satisfied: true } unless dependencies&.any?

dependencies.each do |dependency| unless dependency_satisfied?(dependency) return { satisfied: false, error: "Dependency not satisfied: #{dependency}" } end end

{ satisfied: true } end

def validate_parameters(parameters) parameters.each do |key, value| resolved_value = resolve_tusk_variable(value) case key when "batch_size" unless resolved_value.is_a?(Integer) && resolved_value > 0 return { valid: false, error: "Invalid batch_size: must be positive integer" } end when "source", "destination" unless resolved_value.is_a?(String) && !resolved_value.empty? return { valid: false, error: "Invalid #{key}: must be non-empty string" } end end end

{ valid: true } end

def check_resources(resources) return { available: true } unless resources&.any?

if resources["memory"] available_memory = get_available_memory required_memory = parse_memory_requirement(resources["memory"]) if available_memory < required_memory return { available: false, error: "Insufficient memory: required #{required_memory}MB, available #{available_memory}MB" } end end

{ available: true } end

def execute_job_handler(handler_config, parameters, context) job_class = handler_config[:class].constantize job_instance = job_class.new # Resolve TuskLang variables in parameters resolved_parameters = resolve_parameters(parameters) job_instance.send(handler_config[:method], resolved_parameters, context) rescue => e { success: false, error: e.message, backtrace: e.backtrace.first(5) } end

def resolve_parameters(parameters) parameters.transform_values do |value| resolve_tusk_variable(value) end end

def resolve_tusk_variable(value) return value unless value.is_a?(String) && value.start_with?("@") variable_name = value[1..-1] TuskConfig.get(variable_name) end

def dependency_satisfied?(dependency) # Implementation would check if dependency is met # This could be checking if a file exists, service is running, etc. true end

def get_available_memory # Implementation would get available system memory 8192 # 8GB example end

def parse_memory_requirement(memory_string) # Parse memory requirements like "2GB", "512MB" case memory_string when /(\d+)GB/i then $1.to_i * 1024 when /(\d+)MB/i then $1.to_i else memory_string.to_i end end

def record_metrics(job_name, start_time, end_time, result) execution_time = end_time - start_time metrics = { job_name: job_name, execution_time: execution_time, success: result[:success], timestamp: start_time }

# Store metrics (could be to database, monitoring service, etc.) MetricsRecorder.record(metrics) end

def send_notifications(job_name, job_config, result) notifications = job_config["notifications"] return unless notifications

if result[:success] && notifications["on_success"] send_notification_list(notifications["on_success"], job_name, result, "success") elsif !result[:success] && notifications["on_failure"] send_notification_list(notifications["on_failure"], job_name, result, "failure") end end

def send_notification_list(notification_list, job_name, result, status) notification_list.each do |notification| send_notification(notification, job_name, result, status) end end

def send_notification(notification, job_name, result, status) case notification when /^email:(.+)$/ send_email_notification($1, job_name, result, status) when /^slack:(.+)$/ send_slack_notification($1, job_name, result, status) when /^webhook:(.+)$/ send_webhook_notification($1, job_name, result, status) end end end

Monitoring and Metrics

Monitoring configuration

monitoring_config = { "#cron" => { "monitoring" => { "enabled" => true, "metrics" => { "execution_time" => { "enabled" => true, "alert_threshold" => 300, "aggregation" => "average" }, "success_rate" => { "enabled" => true, "alert_threshold" => 0.95, "aggregation" => "percentage" }, "memory_usage" => { "enabled" => true, "alert_threshold" => "80%", "aggregation" => "max" } }, "alerts" => { "email" => { "enabled" => true, "recipients" => ["admin@example.com", "ops@example.com"] }, "slack" => { "enabled" => true, "channel" => "#cron-alerts" }, "pagerduty" => { "enabled" => true, "service_key" => "@pagerduty_service_key" } }, "dashboard" => { "enabled" => true, "url" => "/cron-dashboard", "refresh_interval" => 30 } } } }

Ruby monitoring processor

class CronMonitoringProcessor def initialize(config) @config = config["#cron"]["monitoring"] @metrics_collector = MetricsCollector.new @alert_manager = AlertManager.new(@config["alerts"]) end

def record_job_execution(job_name, execution_data) return unless @config["enabled"]

# Record basic metrics @metrics_collector.record_execution_time(job_name, execution_data[:execution_time]) @metrics_collector.record_success_rate(job_name, execution_data[:success]) @metrics_collector.record_memory_usage(job_name, execution_data[:memory_usage])

# Check for alerts check_alerts(job_name, execution_data) end

def generate_dashboard_data return {} unless @config["dashboard"]["enabled"]

{ jobs: get_jobs_summary, metrics: get_metrics_summary, alerts: get_active_alerts, system_health: get_system_health } end

private

def check_alerts(job_name, execution_data) @config["metrics"].each do |metric_name, metric_config| next unless metric_config["enabled"]

current_value = get_current_metric_value(job_name, metric_name) threshold = metric_config["alert_threshold"]

if threshold_exceeded?(current_value, threshold, metric_config["aggregation"]) trigger_alert(job_name, metric_name, current_value, threshold) end end end

def get_current_metric_value(job_name, metric_name) case metric_name when "execution_time" @metrics_collector.get_average_execution_time(job_name) when "success_rate" @metrics_collector.get_success_rate(job_name) when "memory_usage" @metrics_collector.get_max_memory_usage(job_name) else 0 end end

def threshold_exceeded?(value, threshold, aggregation) case aggregation when "average", "max" value > threshold when "percentage" value < threshold else false end end

def trigger_alert(job_name, metric_name, value, threshold) alert_data = { job_name: job_name, metric_name: metric_name, current_value: value, threshold: threshold, timestamp: Time.current }

@alert_manager.send_alert(alert_data) end

def get_jobs_summary # Implementation would return summary of all jobs { total_jobs: 10, active_jobs: 8, failed_jobs: 1, running_jobs: 1 } end

def get_metrics_summary # Implementation would return summary of metrics { average_execution_time: 45.2, overall_success_rate: 0.98, total_executions: 1250 } end

def get_active_alerts # Implementation would return active alerts [] end

def get_system_health # Implementation would return system health status { status: "healthy", cpu_usage: 45.2, memory_usage: 67.8, disk_usage: 23.1 } end end

Metrics collector

class MetricsCollector def initialize @redis = Redis.new end

def record_execution_time(job_name, execution_time) key = "cron:metrics:#{job_name}:execution_time" @redis.lpush(key, execution_time) @redis.ltrim(key, 0, 999) # Keep last 1000 records end

def record_success_rate(job_name, success) key = "cron:metrics:#{job_name}:success" @redis.lpush(key, success ? 1 : 0) @redis.ltrim(key, 0, 999) end

def record_memory_usage(job_name, memory_usage) key = "cron:metrics:#{job_name}:memory_usage" @redis.lpush(key, memory_usage) @redis.ltrim(key, 0, 999) end

def get_average_execution_time(job_name) key = "cron:metrics:#{job_name}:execution_time" values = @redis.lrange(key, 0, -1).map(&:to_f) values.empty? ? 0 : values.sum / values.length end

def get_success_rate(job_name) key = "cron:metrics:#{job_name}:success" values = @redis.lrange(key, 0, -1).map(&:to_i) values.empty? ? 1.0 : values.sum.to_f / values.length end

def get_max_memory_usage(job_name) key = "cron:metrics:#{job_name}:memory_usage" values = @redis.lrange(key, 0, -1).map(&:to_f) values.empty? ? 0 : values.max end end

Alert manager

class AlertManager def initialize(alert_config) @alert_config = alert_config end

def send_alert(alert_data) if @alert_config["email"]["enabled"] send_email_alert(alert_data) end

if @alert_config["slack"]["enabled"] send_slack_alert(alert_data) end

if @alert_config["pagerduty"]["enabled"] send_pagerduty_alert(alert_data) end end

private

def send_email_alert(alert_data) recipients = @alert_config["email"]["recipients"] subject = "Cron Alert: #{alert_data[:job_name]}" body = generate_alert_email_body(alert_data)

# Implementation would send email puts "Sending email alert to #{recipients.join(', ')}" end

def send_slack_alert(alert_data) channel = @alert_config["slack"]["channel"] message = generate_slack_alert_message(alert_data)

# Implementation would send Slack message puts "Sending Slack alert to #{channel}" end

def send_pagerduty_alert(alert_data) service_key = resolve_tusk_variable(@alert_config["pagerduty"]["service_key"]) # Implementation would send PagerDuty alert puts "Sending PagerDuty alert" end

def generate_alert_email_body(alert_data) <<~EMAIL Cron Job Alert Job: #{alert_data[:job_name]} Metric: #{alert_data[:metric_name]} Current Value: #{alert_data[:current_value]} Threshold: #{alert_data[:threshold]} Time: #{alert_data[:timestamp]} EMAIL end

def generate_slack_alert_message(alert_data) { text: "🚨 Cron Alert: #{alert_data[:job_name]}", attachments: [ { fields: [ { title: "Metric", value: alert_data[:metric_name], short: true }, { title: "Current Value", value: alert_data[:current_value].to_s, short: true }, { title: "Threshold", value: alert_data[:threshold].to_s, short: true }, { title: "Time", value: alert_data[:timestamp].strftime("%Y-%m-%d %H:%M:%S"), short: true } ] } ] } end

def resolve_tusk_variable(variable) return variable unless variable&.start_with?("@") variable_name = variable[1..-1] TuskConfig.get(variable_name) end end

Integration with Ruby Scheduling Frameworks

Rufus Scheduler integration example

class TuskRufusScheduler include CronDirectiveProcessor

def initialize(config) @tusk_config = load_tusk_config @cron_processor = CronDirectiveProcessor.new(@tusk_config) @job_processor = JobExecutionProcessor.new(@tusk_config) @monitoring_processor = CronMonitoringProcessor.new(@tusk_config) @scheduler = Rufus::Scheduler.new end

def start cron_config = @cron_processor.process_cron_directive return unless cron_config

schedule_jobs(cron_config[:jobs]) start_monitoring end

def stop @scheduler.shutdown end

private

def schedule_jobs(jobs_config) jobs_config.each do |job_name, job_config| next unless job_config[:enabled]

schedule_job(job_name, job_config) end end

def schedule_job(job_name, job_config) schedule = job_config[:schedule] timezone = job_config[:timezone] @scheduler.cron(schedule, tz: timezone) do execute_job_with_monitoring(job_name, job_config) end end

def execute_job_with_monitoring(job_name, job_config) start_time = Time.current memory_before = get_memory_usage

result = @job_processor.execute_job(job_name, job_config)

end_time = Time.current memory_after = get_memory_usage

execution_data = { execution_time: end_time - start_time, success: result[:success], memory_usage: memory_after - memory_before }

@monitoring_processor.record_job_execution(job_name, execution_data) end

def start_monitoring return unless @tusk_config["#cron"]["monitoring"]["enabled"]

# Start monitoring dashboard if enabled if @tusk_config["#cron"]["monitoring"]["dashboard"]["enabled"] start_dashboard_server end end

def start_dashboard_server # Implementation would start a web server for the dashboard puts "Starting cron dashboard server..." end

def get_memory_usage # Implementation would get current memory usage Process.getrusage(:SELF).maxrss end

def load_tusk_config TuskConfig.load("peanu.tsk") end end

Sidekiq integration example

class TuskSidekiqScheduler include CronDirectiveProcessor

def initialize(config) @tusk_config = load_tusk_config @cron_processor = CronDirectiveProcessor.new(@tusk_config) @sidekiq_scheduler = Sidekiq::Scheduler.new end

def schedule_jobs cron_config = @cron_processor.process_cron_directive return unless cron_config

cron_config[:jobs].each do |job_name, job_config| next unless job_config[:enabled]

schedule_sidekiq_job(job_name, job_config) end end

private

def schedule_sidekiq_job(job_name, job_config) schedule = job_config[:schedule] handler_config = job_config[:handler]

@sidekiq_scheduler.cron(schedule) do enqueue_sidekiq_job(handler_config[:class], job_config[:parameters]) end end

def enqueue_sidekiq_job(job_class, parameters) job_class.perform_async(parameters) end

def load_tusk_config TuskConfig.load("peanu.tsk") end end

Example Sidekiq job class

class TuskCronJob include Sidekiq::Worker

def perform(parameters) # Job implementation puts "Executing TuskLang cron job with parameters: #{parameters}" end end

Best Practices and Patterns

Best practices for cron directive usage

class CronDirectiveBestPractices def self.validate_config(config) errors = [] # Check required fields unless config["#cron"] errors << "Missing #cron directive" return errors end

cron_config = config["#cron"] # Validate jobs unless cron_config["jobs"]&.any? errors << "At least one job must be defined" end

# Validate job configurations cron_config["jobs"]&.each do |job_name, job_config| job_errors = validate_job(job_name, job_config) errors.concat(job_errors) end

errors end

def self.optimize_config(config) cron_config = config["#cron"] # Set defaults for jobs cron_config["jobs"]&.each do |job_name, job_config| job_config["timezone"] ||= "UTC" job_config["enabled"] = true if job_config["enabled"].nil? job_config["timeout"] ||= 300 job_config["retry_policy"] ||= { "max_attempts" => 3, "backoff" => "exponential", "delay" => 60 } end

# Set monitoring defaults cron_config["monitoring"] ||= {} cron_config["monitoring"]["enabled"] = true if cron_config["monitoring"]["enabled"].nil?

config end

def self.generate_documentation(config) cron_config = config["#cron"] { jobs: cron_config["jobs"]&.keys, schedules: cron_config["schedules"]&.keys, monitoring_enabled: cron_config["monitoring"]&.dig("enabled"), notifications: cron_config["notifications"]&.keys } end

private

def self.validate_job(job_name, job_config) errors = [] unless job_config["schedule"] errors << "Job #{job_name} must have a schedule" end unless job_config["handler"] errors << "Job #{job_name} must have a handler" end

# Validate schedule format if job_config["schedule"] && !valid_cron_schedule?(job_config["schedule"]) errors << "Job #{job_name} has invalid cron schedule: #{job_config['schedule']}" end

# Validate handler format if job_config["handler"] && !job_config["handler"].include?("#") errors << "Handler must be in format 'Class#method'" end

errors end

def self.valid_cron_schedule?(schedule) # Basic cron schedule validation parts = schedule.split(" ") return false unless parts.length == 5

# This is a simplified validation - in production you'd want more robust validation parts.all? { |part| part.match?(/^[\d*\/,\-]+$/) } end end

Usage example

config = { "#cron" => { "jobs" => { "backup" => { "schedule" => "0 2 *", "handler" => "BackupJob#execute", "description" => "Daily backup" } } } }

Validate and optimize

errors = CronDirectiveBestPractices.validate_config(config) if errors.empty? optimized_config = CronDirectiveBestPractices.optimize_config(config) documentation = CronDirectiveBestPractices.generate_documentation(config) puts "Configuration is valid!" puts "Documentation: #{documentation}" else puts "Configuration errors: #{errors}" end

Conclusion

The Hash Cron Directive in TuskLang represents a revolutionary approach to task scheduling and automation. By combining declarative configuration with Ruby's powerful scheduling capabilities, you can create sophisticated, maintainable automated systems with minimal boilerplate code.

Key benefits: - Declarative Configuration: Define complete scheduled jobs in simple hash structures - Ruby Integration: Leverage Ruby's scheduling frameworks and ecosystem - Advanced Scheduling: Support for complex schedules, timezones, and dependencies - Monitoring and Metrics: Built-in monitoring, alerting, and performance tracking - Error Handling: Comprehensive retry policies and error recovery - Notifications: Flexible notification system for job status updates - Resource Management: Built-in resource monitoring and allocation

Remember, TuskLang is about breaking free from conventions and embracing the power of declarative, configuration-driven development. The Hash Cron Directive is your gateway to building automated systems that are as expressive as they are powerful!