Crate mako_engine 

mako-engine — event-sourced process runtime for German energy market communication (MaKo).

Architecture

Raw EDIFACT bytes (AS4 transport)
        │
        ▼
[edi-energy] parse · validate
        │
        ▼  Command (typed, validated)
EngineContext::spawn / ::resume → Process::execute / ::execute_with / ::execute_with_retry
        │
        ├─ load events → reconstruct state (Workflow::apply + upcast)
        ├─ handle command (Workflow::handle — pure, deterministic)
        └─ append EventEnvelope batch (optimistic concurrency)

EventStore ──► ProjectionRunner ──► Read models
SnapshotStore ──► Process::state_with_snapshot (O(k) replay)
OutboxStore ──► delivery worker ──► AS4 endpoint
DeadlineStore ──► scheduler ──► TimeoutDeadline command
ProcessRegistry ──► inbound message routing ──► Process

Quick start

use mako_engine::{
    builder::EngineBuilder,
    ids::TenantId,
    version::WorkflowId,
    event_store::InMemoryEventStore,
};

let ctx = EngineBuilder::new()
    .with_event_store(InMemoryEventStore::new())
    .build();

// Spawn a new process.
let process = ctx.spawn::<MyWorkflow>(TenantId::new(), WorkflowId::new("…", "FV2024-10-01"));
let envelopes = process.execute(my_command).await?;

// Reconstruct typed state by replaying all events.
let state = process.state().await?;

// Persist routing information and resume on the next message.
ctx.registry().register(tenant, &conv_id.to_string(), process.identity()).await?;
let identity = ctx.registry().lookup(tenant, &conv_id.to_string()).await?.unwrap();
let resumed  = ctx.resume::<MyWorkflow>(identity);

Crate modules

Module	Contents
ids	Typed identifier newtypes (EventId, StreamId, ProcessId, ProcessIdentity, DeadlineId, …)
types	Semantic domain identifiers (MaLo, MeLo, MarktpartnerCode, MessageRef, DeviceId, BkvId, UenbId, BillingPeriod)
version	FormatVersion, WorkflowId, and WorkflowVersionPolicy
envelope	EventEnvelope and NewEvent
error	EngineError, WorkflowError
event_store	EventStore trait (with stream_version) + InMemoryEventStore
workflow	Workflow trait, EventPayload, CommandContext
message_adapter	MessageAdapter trait, AdapterRegistry, FnAdapter — cross-FV command translation
process	Process<W,S> — ergonomic typed process handle
projection	Projection trait + ProjectionRunner (single-stream and multi-stream) + GlobalProjectionCheckpoint
snapshot	Snapshot, SnapshotStore + InMemorySnapshotStore / NoopSnapshotStore
outbox	OutboxMessage, OutboxStore + InMemoryOutboxStore / NoopOutboxStore
inbox	InboxStore trait + InMemoryInboxStore for AS4 retry deduplication
deadline	Deadline, DeadlineStore + InMemoryDeadlineStore / NoopDeadlineStore
registry	ProcessRegistry + InMemoryProcessRegistry / NoopProcessRegistry
pid_router	PidRouter — maps Prüfidentifikator values to workflow names
fristen	Regulatory deadline helpers: add_hours (GPKE 24h), add_werktage (WiM/GeLi/MABIS)
dead_letter	DeadLetterSink trait + LogDeadLetterSink / NoopDeadLetterSink
erp	ErpAdapter, ErpCommandSource, ErpEvent — ERP/backend integration contract (BO4E)
builder	EngineModule trait, EngineBuilder, EngineContext

Modules

builder

EngineModule trait, EngineBuilder, and EngineContext.

dead_letter

Dead-letter sink for unroutable or unprocessable inbound messages.

deadline

Deadline tracking for regulatory process timers.

envelope

The EventEnvelope — the standard wrapper for every persisted event.

erp

ERP integration traits and reference implementations.

error

Engine-level error types.

event_store

EventStore trait and the in-process [InMemoryEventStore] implementation.

fristen

Regulatory deadline calculation helpers.

ids

Typed identifier newtypes for all engine-layer concepts.

inbox

Inbox deduplication for inbound messages.

marktrolle

BDEW Rollenmodell — market-participant role configuration.

message_adapter

MessageAdapter — cross-format-version message-to-command translation.

metrics

EngineMetrics — process-level event counters for Prometheus export.

migration

In-flight process state migration across BDEW format-version boundaries.

outbox

Outbox pattern for reliable at-least-once outbound message delivery.

partner

Trading-partner master data — the PartnerStore trait and supporting types.

pid_router

PID-to-workflow routing table.

process

Process — ergonomic typed handle for a single MaKo process instance.

profile

Profile requirements — decouple domain crates from edi-energy.

projection

Projection trait and ProjectionRunner.

registry

Process routing registry.

snapshot

Snapshotting support — a performance optimisation for long event streams.

types

Semantic domain type wrappers for identifiers used across all MaKo process families.

version

Workflow versioning types.

workflow

Workflow trait, EventPayload, CommandPayload, and CommandContext.

Macros

bo4e_schema_url

Construct a BO4E v202501.0.0 JSON Schema URL for a Business Object.