Execute.

From target book to broker order

The Nexus overview shows step 4 as orders passing staged limits on their way to the broker. This is the whole path, and every step of it runs every trading day.

1. 1

   Promoted book

   An account trades only the research book promoted for it. If that link is unknown or wrong, new risk is removed and exits still go out.

2. 2

   Same sizing

   The trader and research pin the same position engine, so a backtest and the live book can't disagree about how a signal becomes a position.

3. 3

   Checked

   The book is built only when every input market's data is complete. A closed market takes no orders, and stakes are rounded to the broker's deal steps.

4. 4

   Sent

   Every order passes the pre-trade limits. A flip is a close, then an open that is sent only after the close confirms.

5. 5

   Reconciled

   Positions are checked against the broker before every cycle. Funding and fills are reconciled every night.

For your firmEvery trading day starts with a full-book dry run before the first slot, 78 of them since 24 August, so the day's orders are rehearsed before any reach the broker.

Limits that never trap a position

Every order is checked against size, notional and position limits, set for 122 scopes from a single instrument up to a whole asset class. The limits are staged from off to warn to block, and the next stage is switched on only when the evidence says it is safe.

• Size, notional, positionRuns

  Maximum order size, maximum notional and maximum position are checked on every order, and any breach is written on the order record itself.

• Risk-reducing always passesRuns

  No stage ever refuses an order that reduces a position, so a limit can't trap the book. The check still runs and is recorded.

• Price collarsRuns · warn

  Each order's price is compared with an independently captured price, and unusable quotes are caught.

• Margin capRuns

  A margin cap trims the plan or stops the run before anything reaches the broker. It has never had to fire in production, and a drill proved that it works.

• Early warningRuns

  Alerts fire at 50% and 80% of a limit, with hysteresis so they don't flap.

• Block modeBuilt, tested

  Block mode refuses a breach, and it refuses any instrument that has no limit set. It goes live only once a replay of real fills under block refuses nothing. The last replay still refused one real order, so production runs at warn.

Independent brakes, any one of which stops trading

One broker client, paced and measured

A single IG REST client places orders, confirms them and reads positions, for a demo or a live account by configuration. It starts on the demo endpoint, in dry run, unless it is told otherwise.

Reconciled before every cycle, and again every night

A reconciliation is only useful if it can stop trading. The position check can, and it has: 74 live runs were stopped because the books didn't agree or the check couldn't finish.

• Positions, before every cycleRuns

  Positions are checked against the broker before each trading cycle, and a break halts the run. There have been 1,085 checks since 26 July. Since 15 September, 227 of 230 were clean.

• Book against researchRuns

  A daily check compares the trader's book with research's targets. It has run 182 times and halted trading 3 times.

• Funding, nightlyRuns

  IG transaction history is pulled every night and reconciled against the model's funding, and breaks are flagged for follow-up.

• Portfolio ledgerRuns

  Fills sync into the portfolio ledger every night: 361 transactions over 53 runs since 23 August.

• Next-morning auditRuns

  Each trading day is audited the next morning, 168 times so far.

• Broker statementsBuilt

  Reconciliation against the broker's statements is built and has not run yet.

Each market at its own exchange's time

A resident scheduler trades each of 37 markets at its local exchange time, in Chicago, New York and London, and stays correct across daylight-saving changes. It made 908 live runs over 90 trading days, from 7 July to 14 October.

• Idempotent. A slot that has already run doesn't run again.
• Dry run by default. Sending real orders is an explicit setting, never an accident.
• Data first. A market trades only when its inputs are complete.
• Rehearsed daily. A full-book dry run comes before the first slot of every trading day.

How it is scheduledEvery trading job is a systemd unit on the production host, with no separate job framework: Scheduled by systemd.

What runs, stated plainly

Each control is shown at the stage it has reached in production.

• Every broker order so far has been on IG demo accounts. No live account has placed an order, and going live is an operator decision that is still open.
• The brakes stop new orders. They don't cancel orders resting at the broker, close positions or end the broker session; flatten does the closing.
• Reconciliation reports breaks rather than claiming a clean record, and some funding breaks are open now.
• One broker (IG spread bets), one production host and one operator.
• This page describes the framework. It shows no trading results and makes no performance claim.

Sources, read 2026-10-15: the trader's order, account, schedule, scheduler-run, limit, reconciliation and drill records; the portfolio ledger's sync runs; the deployed versions of the trader and the research service; the trader's code and documentation on its main branch; and the handbook's status page.