Frequently asked questions

Voltnir is EPEX SPOT M7 intraday trading middleware for power desks. It is a self-hosted gateway that connects your desk to the EPEX SPOT intraday continuous market and exposes it over REST, WebSocket and gRPC, maintaining the order book, validating orders, and tracking position, cash and P&L in real time.

The EPEX SPOT intraday continuous market on the M7 trading system, and nothing else. You configure the delivery areas your EPEX SPOT membership is admitted to, by EIC code, and the M7 products you want; Voltnir maintains the book and risk for exactly that set. Contract granularity follows M7, hourly through quarter-hourly.

No. Voltnir is the market-access layer, not the brain. It owns the exchange connection, the order book, validation, risk checks and audit, and executes the orders you send. Your models, signals and forecasts never enter it. And it trades the EPEX SPOT intraday continuous market only; day-ahead and auction trading run on a different EPEX SPOT system and are out of scope.

Self-hosted. Voltnir runs in your environment, not ours: a single static binary on your own infrastructure, with your EPEX SPOT credentials and your trading data staying on your side. There is no Voltnir-operated cloud in the trading path.

A Linux host you control, your EPEX SPOT credentials, and a licence file from the customer portal. Voltnir ships as one static binary with an embedded database, so there is nothing else to install; point it at your own PostgreSQL instead when you want an external store. The connection to EPEX SPOT is outbound only; you open nothing inbound toward the exchange.

Three transports over one contract: a REST API, a WebSocket feed, and gRPC. Trading, market data and account operations are available on all three with the same fields, permissions and units. Report exports and terminal sign-in sessions are REST only. Live contracts, orders, trades and P&L stream over both WebSocket and gRPC.

Over whichever transport fits your stack: REST, WebSocket or gRPC. Trading, market data and account operations are available on all three with identical fields, units and permissions. Report exports and terminal sign-in sessions are REST only. There is also a Python gRPC SDK and the published service definition for generated clients in other languages. The bundled trading terminal is built on the same public API, so anything it shows, your own code can read the same way.

No. Voltnir speaks the EPEX SPOT API for you. It holds the M7 session, AMQP for orders and WebSocket for market data, keeps the order book, checks risk before an order leaves, and exposes all of it over REST, WebSocket and gRPC. Your code never touches the exchange protocol, and the exchange never sees anything but a conformant M7 client.

The full M7 order-entry model: regular limit, iceberg, block, balance and pre-arranged orders, together with the M7 execution restrictions (AON, FOK, IOC), the validity rules, and hibernated entry. Every order is validated as one combination before anything reaches the exchange, with the same fields and the same rules on REST, WebSocket and gRPC.

Layered pre-trade checks enforced in the gateway before any order reaches M7: a house-wide position limit per contract plus independent per-member limits, a slot limit that caps the net position in each quarter-hour of each delivery area summed over every contract delivering in it (house-wide and per member, off by default, with an observe mode that audits what it would refuse before you switch it to reject), a cash limit taken directly from the exchange in separate EUR and GBP pools with no fail-open mode (a limit of zero means no trading in that pool, always), each virtual member holding a fixed share of that limit no other member can spend, each virtual member trading only in the delivery areas it is given, self-trade prevention, and a global kill-switch that halts order entry and sends a cancel-all to the exchange so the resting book is flattened, live, with no restart. Every limit change is permission-gated and lands in the audit trail.

Yes. An append-only trail of every state-changing action, stamped with who did it, from where, over which transport, and the exact before and after of what changed. Orders, trades and every fault the exchange returns are recorded with per-user attribution, and all of it is queryable on every transport, with order, trade and audit-trail exports over REST and retention you choose.

Yes. The binary serves a React trading terminal built on the exact public API any client uses: live order-book depth, an order ticket with a pre-trade market-impact preview, the public trade tape, real-time P&L, a cross-border capacity map of Europe, and the operator pages for users, members and limits.

The gateway is a single Rust binary with no garbage collector, so nothing pauses between a market-data frame arriving and the book updating. Voltnir publishes the timings it measured on the EPEX SPOT simulation environment over about 12 hours and 4,000 orders: an order-book delta applied in a mean of 12 μs and an order handed to the M7 connection in a mean of 118 μs on a dedicated 8-core server, 30 μs and 480 μs on a shared 2 vCPU VM. Admission, the pre-trade checks, has a p99 of 98.1 μs on the dedicated server. The gateway also times itself continuously and exposes the same stages on its OpenMetrics endpoint, which Prometheus or any OpenMetrics collector can scrape, and in the terminal, so you read latency from your own install and your own network path, not from a datasheet.

Yes. Voltnir is multi-tenant and white-label: one EPEX SPOT membership can carry multiple desks, each with its own users, per-member limits and role-based access control, isolated position and cash tracking, and an append-only audit trail.

Against a signed licence file the binary verifies at startup, offline. There is no licence server to call and nothing phones home. The licence fixes the environment it may reach (a simulator licence can never trade production), the EPEX SPOT identity it may trade as, the tier it runs at (Trader, or Desk with user and member management), and the date it expires. Renewing is a new file and a restart.

Yes. Voltnir is a certified Independent Software Vendor (ISV) of EPEX SPOT for the M7 intraday continuous market. Certification means the software passed EPEX SPOT's conformance tests against its trading products and market specifications, and Voltnir is listed on the exchange's software-providers page. For your desk it means the exchange does not ask you to pass the M7 conformance test, because Voltnir already has: you request simulation and production access for an ISV application and go live on software the exchange has already tested.

Download a free simulator licence from the customer portal and run Voltnir against the EPEX SPOT SIM environment in minutes, with no sales call. The Voltnir simulator licence is free; the one thing you need from EPEX SPOT itself is their simulation licence, the ASIM licence, which issues the SIM credentials Voltnir connects with.