// TFVersion is the version of Terraform that wrote this state.
TFVersion string `json:"terraform_version,omitempty"`

// Serial is incremented on any operation that modifies
// the State file. It is used to detect potentially conflicting
// updates.
Serial int64 `json:"serial"`

// Lineage is set when a new, blank state is created and then
// never updated. This allows us to determine whether the serials
// of two states can be meaningfully compared.
// Apart from the guarantee that collisions between two lineages
// are very unlikely, this value is opaque and external callers
// should only compare lineage strings byte-for-byte for equality.
Lineage string `json:"lineage"`

// Remote is used to track the metadata required to
// pull and push state files from a remote storage endpoint.
Remote *RemoteState `json:"remote,omitempty"`

// Backend tracks the configuration for the backend in use with
// this state. This is used to track any changes in the backend
// configuration.
Backend *BackendState `json:"backend,omitempty"`

// Modules contains all the modules in a breadth-first order
Modules []*ModuleState `json:"modules"`

mu sync.Mutex