diff --git a/example/.tflint.hcl b/example/.tflint.hcl
new file mode 100644
index 0000000..e927895
--- /dev/null
+++ b/example/.tflint.hcl
@@ -0,0 +1,16 @@
+plugin "terraform" {
+  enabled = true
+  preset  = "recommended"
+}
+
+rule "terraform_unused_declarations" {
+  enabled = true
+}
+
+# rule "terraform_documented_outputs" {
+#  enabled = true
+# }
+
+rule "terraform_documented_variables" {
+  enabled = true
+}
diff --git a/example/providers.tf b/example/providers.tf
index 502d800..5873620 100644
--- a/example/providers.tf
+++ b/example/providers.tf
@@ -3,7 +3,7 @@ terraform {
   required_providers {
     stackit = {
       source  = "stackitcloud/stackit"
-      version = "0.54.0"
+      version = "0.56.0"
     }
   }
 }
diff --git a/example/variables.tf b/example/variables.tf
index bfeab6e..dff5a62 100644
--- a/example/variables.tf
+++ b/example/variables.tf
@@ -61,10 +61,6 @@ variable "labels" {
   default     = {}
 }
 
-# -----------------------------------------------------------------------------#
-# Security Groups
-# -----------------------------------------------------------------------------#
-
 variable "security_groups" {
   description = "Map of security group definitions"
   type = map(object({
@@ -93,10 +89,6 @@ variable "security_groups" {
   }))
 }
 
-# -----------------------------------------------------------------------------#
-# PostgreSQL
-# -----------------------------------------------------------------------------#
-
 variable "postgres_instances" {
   description = "Map of PostgreSQL instances to create"
   type = map(object({
@@ -119,10 +111,6 @@ variable "postgres_instances" {
   }))
 }
 
-# -----------------------------------------------------------------------------#
-# Networks
-# -----------------------------------------------------------------------------#
-
 variable "networks" {
   description = "Map of network definitions per project"
   type = map(object({
@@ -219,10 +207,6 @@ variable "ske_clusters" {
   default = {}
 }
 
-# -----------------------------------------------------------------------------#
-# Observability
-# -----------------------------------------------------------------------------#
-
 variable "observability_instances" {
   description = "Map of Observability instances to create"
   type = map(object({
diff --git a/main.tf b/main.tf
new file mode 100644
index 0000000..93ef132
--- /dev/null
+++ b/main.tf
@@ -0,0 +1,130 @@
+resource "stackit_network_area" "project_sna" {
+  organization_id  = var.organization_id
+  name             = var.SNA_name
+  network_ranges   = var.SNA_network_ranges
+  transfer_network = var.SNA_transfer_network
+}
+
+module "projects" {
+  source = "./project"
+
+  projects        = var.Projects_map
+  organization_id = var.organization_id
+  sna_id          = stackit_network_area.project_sna.network_area_id
+  labels          = var.labels != null ? var.labels : {}
+}
+
+locals {
+  project_ids = { for k, v in module.projects.created_projects : k => v.project_id }
+}
+
+module "stackit_ske_cluster" {
+  source = "./ske"
+  for_each = var.ske_clusters
+
+  project_id = local.project_ids[each.value.project_key]
+  name       = each.value.name
+  node_pools = each.value.node_pools
+  kubernetes_version_min = lookup(each.value, "kubernetes_version_min", null)
+  hibernations           = lookup(each.value, "hibernations", null)
+  maintenance            = lookup(each.value, "maintenance", null)
+  extensions             = lookup(each.value, "extensions", null)
+  default_region         = var.default_region
+}
+
+module "security_groups" {
+  source = "./security-group"
+
+  for_each = var.security_groups
+
+  project_id  = local.project_ids[each.value.project_key]
+  name        = each.value.name
+  description = each.value.description != null ? each.value.description : ""
+  rules       = each.value.rules
+}
+
+locals {
+  security_group_ids_by_name = {
+    for key, m in module.security_groups :
+    m.name => m.security_group_id
+  }
+}
+
+module "net" {
+  depends_on = [module.security_groups]
+  source     = "./network"
+
+  for_each = var.networks
+
+  project_id = local.project_ids[each.value.project_key]
+  name       = each.value.name
+
+  ipv4_gateway       = each.value.ipv4_gateway
+  ipv4_nameservers   = each.value.ipv4_nameservers
+  ipv4_prefix        = each.value.ipv4_prefix
+  ipv4_prefix_length = each.value.ipv4_prefix_length
+
+  ipv6_gateway       = each.value.ipv6_gateway
+  ipv6_nameservers   = each.value.ipv6_nameservers
+  ipv6_prefix        = each.value.ipv6_prefix
+  ipv6_prefix_length = each.value.ipv6_prefix_length
+
+  no_ipv4_gateway = each.value.no_ipv4_gateway
+  no_ipv6_gateway = each.value.no_ipv6_gateway
+  routed          = each.value.routed
+  labels          = each.value.labels
+
+  nics                       = each.value.nics
+  security_group_ids_by_name = local.security_group_ids_by_name
+}
+
+module "postgres" {
+  source = "./postgres"
+
+  for_each = var.postgres_instances
+
+  project_id      = local.project_ids[each.value.project_key]
+  name            = each.value.name
+  ver             = each.value.version
+  flavor          = each.value.flavor
+  storage         = each.value.storage
+  replicas        = each.value.replicas
+  acl             = each.value.acl
+  backup_schedule = each.value.backup_schedule
+  users           = each.value.users
+  databases       = each.value.databases
+}
+
+module "observability" {
+  source   = "./observability"
+  for_each = var.observability_instances
+
+  project_id = local.project_ids[each.value.project_key]
+
+  name      = each.value.name
+  plan_name = each.value.plan_name
+
+  acl                                    = each.value.acl
+  metrics_retention_days                 = each.value.metrics_retention_days
+  metrics_retention_days_5m_downsampling = each.value.metrics_retention_days_5m_downsampling
+  metrics_retention_days_1h_downsampling = each.value.metrics_retention_days_1h_downsampling
+  alert_config                           = each.value.alert_config
+  parameters                             = each.value.parameters
+
+  # Credentials
+  create_credentials = each.value.create_credentials
+  credentials_count  = each.value.credentials_count
+
+  alertgroups = each.value.alertgroups
+
+  logalertgroups = each.value.logalertgroups
+
+  scrapeconfigs = each.value.scrapeconfigs
+}
+
+output "obs_url" {
+  value = {
+    for key, instance in module.observability :
+    key => instance.observability_urls
+  }
+}
diff --git a/network/providers.tf b/network/providers.tf
index 532c77d..6e038c3 100644
--- a/network/providers.tf
+++ b/network/providers.tf
@@ -3,7 +3,7 @@ terraform {
   required_providers {
     stackit = {
       source  = "stackitcloud/stackit"
-      version = "0.54.0"
+      version = "0.56.0"
     }
   }
 }
diff --git a/network/variables.tf b/network/variables.tf
index b5b2fc7..9c7f985 100644
--- a/network/variables.tf
+++ b/network/variables.tf
@@ -8,9 +8,6 @@ variable "name" {
   type        = string
 }
 
-# -----------------------------
-# IPv4
-# -----------------------------
 variable "ipv4_gateway" {
   description = "IPv4 gateway address"
   type        = string
@@ -35,9 +32,6 @@ variable "ipv4_prefix_length" {
   default     = null
 }
 
-# -----------------------------
-# IPv6
-# -----------------------------
 variable "ipv6_gateway" {
   description = "IPv6 gateway address"
   type        = string
@@ -62,18 +56,12 @@ variable "ipv6_prefix_length" {
   default     = null
 }
 
-# -----------------------------
-# Deprecated legacy nameservers (provider still exposes)
-# -----------------------------
 variable "nameservers" {
   description = "Deprecated nameserver list (legacy field)"
   type        = list(string)
   default     = []
 }
 
-# -----------------------------
-# Labels & flags
-# -----------------------------
 variable "labels" {
   description = "Labels map"
   type        = map(string)
@@ -98,9 +86,6 @@ variable "routed" {
   default     = null
 }
 
-# -----------------------------
-# Region override & routing
-# -----------------------------
 variable "region" {
   description = "Resource region override (defaults to provider region)"
   type        = string
@@ -113,9 +98,6 @@ variable "routing_table_id" {
   default     = null
 }
 
-# -----------------------------
-# NIC map (zero or many)
-# -----------------------------
 variable "nics" {
   description = "Map of NIC configs"
   type = map(object({
@@ -130,9 +112,6 @@ variable "nics" {
   default = {}
 }
 
-# -----------------------------
-# Security group lookup map
-# -----------------------------
 variable "security_group_ids_by_name" {
   description = "Security group name→ID map"
   type        = map(string)
diff --git a/observability/providers.tf b/observability/providers.tf
index a2af181..8962cf6 100644
--- a/observability/providers.tf
+++ b/observability/providers.tf
@@ -4,7 +4,7 @@ terraform {
   required_providers {
     stackit = {
       source  = "stackitcloud/stackit"
-      version = "0.54.0"
+      version = "0.56.0"
     }
   }
 }
diff --git a/postgres/providers.tf b/postgres/providers.tf
index 532c77d..6e038c3 100644
--- a/postgres/providers.tf
+++ b/postgres/providers.tf
@@ -3,7 +3,7 @@ terraform {
   required_providers {
     stackit = {
       source  = "stackitcloud/stackit"
-      version = "0.54.0"
+      version = "0.56.0"
     }
   }
 }
diff --git a/project/providers.tf b/project/providers.tf
index 532c77d..6e038c3 100644
--- a/project/providers.tf
+++ b/project/providers.tf
@@ -3,7 +3,7 @@ terraform {
   required_providers {
     stackit = {
       source  = "stackitcloud/stackit"
-      version = "0.54.0"
+      version = "0.56.0"
     }
   }
 }
diff --git a/providers.tf b/providers.tf
new file mode 100644
index 0000000..5873620
--- /dev/null
+++ b/providers.tf
@@ -0,0 +1,16 @@
+terraform {
+  required_version = ">= 1.9.0"
+  required_providers {
+    stackit = {
+      source  = "stackitcloud/stackit"
+      version = "0.56.0"
+    }
+  }
+}
+
+provider "stackit" {
+  default_region           = var.region
+  service_account_token    = var.service_account_token != null ? var.service_account_token : null
+  service_account_key_path = var.service_account_key_path != null ? var.service_account_key_path : null
+  enable_beta_resources    = true
+}
diff --git a/security-group/providers.tf b/security-group/providers.tf
index 532c77d..6e038c3 100644
--- a/security-group/providers.tf
+++ b/security-group/providers.tf
@@ -3,7 +3,7 @@ terraform {
   required_providers {
     stackit = {
       source  = "stackitcloud/stackit"
-      version = "0.54.0"
+      version = "0.56.0"
     }
   }
 }
diff --git a/security-group/variables.tf b/security-group/variables.tf
index 4ca3116..97d6da7 100644
--- a/security-group/variables.tf
+++ b/security-group/variables.tf
@@ -52,7 +52,6 @@ variable "rules" {
     error_message = "Each rule.ether_type must be 'IPv4' or 'IPv6' when set."
   }
 
-  # port_range min <= max when provided
   validation {
     condition = alltrue([
       for r in var.rules :
diff --git a/ske/providers.tf b/ske/providers.tf
index 532c77d..6e038c3 100644
--- a/ske/providers.tf
+++ b/ske/providers.tf
@@ -3,7 +3,7 @@ terraform {
   required_providers {
     stackit = {
       source  = "stackitcloud/stackit"
-      version = "0.54.0"
+      version = "0.56.0"
     }
   }
 }
diff --git a/ske/variables.tf b/ske/variables.tf
index 6636f12..efa26e0 100644
--- a/ske/variables.tf
+++ b/ske/variables.tf
@@ -34,10 +34,6 @@ variable "node_pools" {
   }))
 }
 
-# -----------------------------------------------------------------------------#
-# Optional fields
-# -----------------------------------------------------------------------------#
-
 variable "kubernetes_version_min" {
   description = "Minimum Kubernetes version"
   type        = string
diff --git a/variables.tf b/variables.tf
new file mode 100644
index 0000000..54c97e1
--- /dev/null
+++ b/variables.tf
@@ -0,0 +1,351 @@
+# -----------------------------------------------------------------------------
+# STACKIT Cloud: Core Configuration Variables
+# -----------------------------------------------------------------------------
+
+# Provider region where STACKIT services will be deployed
+variable "region" {
+  description = "Provider region for STACKIT Cloud"
+  type        = string
+  default     = "eu01"
+}
+
+# Token for service account authentication (sensitive)
+variable "service_account_token" {
+  description = "Service account token for authentication"
+  sensitive   = true
+  type        = string
+  default     = null
+}
+
+# -----------------------------------------------------------------------------
+# Subscriber Network Area (SNA) & Project Settings
+# -----------------------------------------------------------------------------
+
+# ID of the STACKIT organization container
+variable "organization_id" {
+  description = "STACKIT organization container ID"
+  type        = string
+}
+
+# Local path to the JSON key for the service account
+variable "service_account_key_path" {
+  description = "Path to service account JSON key"
+  type        = string
+  default     = "/Users/schlenz/.stackit/sa.json"
+}
+
+# Fallback region for resources if none specified
+variable "default_region" {
+  description = "Default region fallback for created resources"
+  type        = string
+  default     = "eu01"
+}
+
+# Name for the Service Network Area (SNA)
+variable "SNA_name" {
+  description = "Name of the Service Network Area to create"
+  type        = string
+}
+
+# List of CIDR prefixes for the Service Network Area network ranges
+variable "SNA_network_ranges" {
+  description = "CIDR list for the Service Network Area"
+  type        = list(object({ prefix = string }))
+}
+
+# CIDR block used for transfer network within the SNA
+variable "SNA_transfer_network" {
+  description = "Transfer network CIDR for the SNA"
+  type        = string
+}
+
+# Map of project keys to project definitions (name and owner email)
+variable "Projects_map" {
+  description = "Map of STACKIT projects to create"
+  type = map(object({
+    name        = string
+    owner_email = string
+  }))
+}
+
+# Default labels applied to resources where supported
+variable "labels" {
+  description = "Default labels to apply where supported"
+  type        = map(string)
+  default     = {}
+}
+
+# Security group definitions, including rules and associations
+variable "security_groups" {
+  description = "Map of security group definitions"
+  type = map(object({
+    name        = optional(string)
+    project_key = string
+    description = optional(string)
+    rules = list(object({
+      direction   = string                   # e.g., ingress or egress
+      description = optional(string)         # description of the rule
+      ether_type  = optional(string)         # IPv4 or IPv6
+      icmp_parameters = optional(object({    # ICMP type/code when applicable
+        type = optional(number)
+        code = optional(number)
+      }))
+      ip_range = optional(string)            # source/destination IP range
+      port_range = optional(object({         # TCP/UDP port range
+        min = number
+        max = number
+      }))
+      protocol = optional(object({            # protocol name/number
+        name   = optional(string)
+        number = optional(number)
+      }))
+      remote_security_group_id = optional(string) # reference another group
+    }))
+  }))
+}
+
+# -----------------------------------------------------------------------------
+# PostgreSQL Database Instances
+# -----------------------------------------------------------------------------
+
+# Definitions for PostgreSQL instances (name, sizing, ACLs, users, and databases)
+variable "postgres_instances" {
+  description = "Map of PostgreSQL instances to create"
+  type = map(object({
+    name        = string
+    project_key = string
+    version     = number
+    flavor      = object({ cpu = number, ram = number })
+    storage     = object({ class = string, size = number })
+    replicas    = number
+    acl         = list(string)              # allowed IP CIDRs
+    backup_schedule = string                # cron-like schedule
+    users = list(object({                   # DB users and their roles
+      username = string
+      roles    = set(string)
+    }))
+    databases = list(object({                # databases to create
+      name  = string
+      owner = string
+    }))
+  }))
+}
+
+# -----------------------------------------------------------------------------
+# Virtual Networks per Project
+# -----------------------------------------------------------------------------
+
+# Network definitions, including IPv4/IPv6 settings, labels, and NICs
+variable "networks" {
+  description = "Map of network definitions per project"
+  type = map(object({
+    name        = string
+    project_key = string
+
+    # IPv4 configuration
+    ipv4_gateway       = optional(string)
+    ipv4_nameservers   = optional(list(string))
+    ipv4_prefix        = optional(string)
+    ipv4_prefix_length = optional(number)
+
+    # IPv6 configuration
+    ipv6_gateway       = optional(string)
+    ipv6_nameservers   = optional(list(string))
+    ipv6_prefix        = optional(string)
+    ipv6_prefix_length = optional(number)
+
+    # Additional flags and resource labels
+    labels          = optional(map(string))
+    no_ipv4_gateway = optional(bool)
+    no_ipv6_gateway = optional(bool)
+    routed          = optional(bool)
+
+    # Network interface cards (NICs) definitions
+    nics = optional(map(object({
+      nic_ipv4                 = optional(string)
+      nic_name                 = string
+      nic_allowed_addresses    = optional(list(string))
+      nic_labels               = optional(map(string))
+      nic_security             = optional(bool)
+      nic_security_group_ids   = optional(list(string))
+      nic_security_group_names = optional(list(string))
+    })))
+  }))
+  default = {}
+}
+
+# -----------------------------------------------------------------------------
+# SKE Kubernetes Clusters
+# -----------------------------------------------------------------------------
+
+# Configuration for SKE clusters, node pools, and optional extensions
+variable "ske_clusters" {
+  description = "Map of SKE cluster definitions"
+  type = map(object({
+    name                   = string
+    project_key            = string
+    kubernetes_version_min = optional(string)
+
+    # Scheduled cluster hibernations
+    hibernations = optional(list(object({
+      start    = string            # local time window start
+      end      = string            # local time window end
+      timezone = optional(string)  # timezone of the schedule
+    })))
+
+    # Maintenance window settings
+    maintenance = optional(object({
+      enable_kubernetes_version_updates    = bool
+      enable_machine_image_version_updates = bool
+      start                                = string
+      end                                  = string
+    }))
+
+    # Cluster extensions (ACL, Argus monitoring)
+    extensions = optional(object({
+      acl = optional(object({
+        enabled       = bool
+        allowed_cidrs = list(string)
+      }))
+      argus = optional(object({
+        enabled           = bool
+        argus_instance_id = string
+      }))
+    }))
+
+    # Node pool definitions (machine types, scaling, labels, taints)
+    node_pools = list(object({
+      name               = string
+      machine_type       = string
+      availability_zones = list(string)
+      minimum            = number
+      maximum            = number
+
+      allow_system_components = optional(bool)
+      cri                     = optional(string)
+      labels                  = optional(map(string))
+      max_surge               = optional(number)
+      max_unavailable         = optional(number)
+      os_name                 = optional(string)
+      os_version_min          = optional(string)
+      volume_size             = optional(number)
+      volume_type             = optional(string)
+      taints = optional(list(object({
+        effect = string
+        key    = string
+        value  = optional(string)
+      })))
+    }))
+  }))
+  default = {}
+}
+
+# -----------------------------------------------------------------------------
+# Observability Instances (Monitoring & Alerting)
+# -----------------------------------------------------------------------------
+
+# Definitions for Observability service instances and alert configurations
+variable "observability_instances" {
+  description = "Map of Observability instances to create"
+  type = map(object({
+    name        = string
+    project_key = string
+    plan_name   = string           # e.g., Observability-Medium-EU01
+
+    # Retention and ACL settings
+    acl                                    = optional(list(string))
+    metrics_retention_days                 = optional(number)
+    metrics_retention_days_5m_downsampling = optional(number)
+    metrics_retention_days_1h_downsampling = optional(number)
+    alert_config                           = optional(any)
+    parameters                             = optional(map(string))
+
+    # Credential generation settings
+    create_credentials = optional(bool, true)
+    credentials_count  = optional(number, 1)
+
+    # Alert group definitions
+    alertgroups = optional(map(object({
+      name     = string
+      interval = optional(string)
+      rules = list(object({
+        alert       = string
+        expression  = string
+        for         = optional(string)
+        labels      = optional(map(string))
+        annotations = optional(map(string))
+      }))
+    })), {})
+
+    # Log alert group definitions
+    logalertgroups = optional(map(object({
+      name     = string
+      interval = optional(string)
+      rules = list(object({
+        alert       = string
+        expression  = string
+        for         = optional(string)
+        labels      = optional(map(string))
+        annotations = optional(map(string))
+      }))
+    })), {})
+
+    # Scrape configuration for metrics collection
+    scrapeconfigs = optional(map(object({
+      name         = string
+      metrics_path = string
+      targets = list(object({
+        urls   = list(string)
+        labels = optional(map(string))
+      }))
+      basic_auth = optional(object({
+        username = string
+        password = string
+      }))
+      saml2 = optional(object({
+        enable_url_parameters = optional(bool)
+      }))
+      sample_limit    = optional(number)
+      scheme          = optional(string)
+      scrape_interval = optional(string)
+      scrape_timeout  = optional(string)
+    })), {})
+  }))
+  default = {}
+
+  validation {
+    condition = alltrue([
+      for k, v in var.observability_instances :
+      contains([
+        "Observability-Medium-EU01",
+        "Observability-Monitoring-XL-EU01",
+        "Observability-Large-EU01",
+        "Observability-Monitoring-Basic-EU01",
+        "Observability-Monitoring-Large-EU01",
+        "Observability-Basic-EU01",
+        "Observability-Monitoring-Medium-EU01",
+        "Observability-Monitoring-XXL-EU01",
+        "Observability-Metrics-Endpoint-100k-EU01",
+        "Observability-Frontend-Starter-EU01",
+        "Observability-Monitoring-Starter-EU01",
+        "Observability-Starter-EU01",
+      ], v.plan_name)
+    ])
+    error_message = <<-EOM
+One or more observability_instances specify an invalid plan_name.
+See the provider error output for supported plans. Allowed:
+    Observability-Medium-EU01
+    Observability-Monitoring-XL-EU01
+    Observability-Large-EU01
+    Observability-Monitoring-Basic-EU01
+    Observability-Monitoring-Large-EU01
+    Observability-Basic-EU01
+    Observability-Monitoring-Medium-EU01
+    Observability-Monitoring-XXL-EU01
+    Observability-Metrics-Endpoint-100k-EU01
+    Observability-Frontend-Starter-EU01
+    Observability-Monitoring-Starter-EU01
+    Observability-Starter-EU01
+EOM
+  }
+}