Portfolio rebalancing infrastructure for European investment platforms
Connects to 14 exchanges. Optimizes for tax lots. Settles T+2. What private wealth charges 80bps for — your API delivers at 15.
POST /v1/portfolios/pf_3x8k2m/rebalance
Authorization: Bearer sk_live_••••••••
Content-Type: application/json
{
"target_weights": {
"IE00B4L5Y983": 0.60,
"LU0908500753": 0.25,
"DE0008469008": 0.15
},
"tax_method": "HIFO",
"drift_threshold": 0.05
}{
"rebalance_id": "rb_7z4n9q",
"status": "completed",
"order_sequence": [{
"isin": "IE00B4L5Y983",
"exchange": "XEUR",
"side": "buy",
"quantity": 142,
"tax_lot_id": "tl_2025_03_18",
"est_settlement": "2026-06-23"
}],
"tax_impact_eur": -312.40
}European exchange fragmentation is an infrastructure problem, not a project
14 different order protocols — FIX/4.4, proprietary REST, venue-specific ITCH feeds. Divergent tax jurisdictions: FIFO mandatory in Germany (§20 EStG), HIFO optimal in the UK, average cost for pension wrappers. T+2 settlement windows that shift on exchange-specific public holidays. ISA and PEA wrapper rules. Withholding tax across five dividend jurisdictions.
Building this in-house means 18–24 months before you process a single retail rebalance — and it never stops needing maintenance as market structure changes. Portfolwright takes that to two weeks, and maintains it ongoing.
Three layers. One API.
Everything you need to launch rebalancing in two weeks — not eighteen months.
Rebalancing Engine
Continuous drift detection against target weights. FIFO and HIFO tax lot selection. Minimum-order logic to reduce unnecessary turnover.
- Drift threshold configuration (1–10%)
- Tax lot optimization per jurisdiction
- Cash buffer management
Exchange Connectivity
14 European exchanges via a single normalized order interface. Real-time fill confirmations. Settlement calendar awareness built in.
- Unified order struct across all exchanges
- Real-time fill webhooks
- T+2 settlement sequencing
Tax Optimizer
Jurisdiction-aware lot sequencing across UK ISA, French PEA, and German Depot accounts. MiFID II Article 25 compliance records generated automatically.
- ISA / PEA wrapper-aware lot selection
- MiFID II trade record export
- Withholding tax tracking
Three steps to a production rebalance
POST target weights
Send target allocation percentages per ISIN, tax method preference, and drift threshold.
POST /v1/portfolios/{id}/rebalance
Engine calculates optimal sequence
Portfolwright detects drift, selects optimal tax lots, sequences orders across exchanges with T+2 settlement awareness.
Webhook: rebalance.calculated
Receive order_sequence[]
Each leg returns exchange, quantity, tax_lot_id, and estimated settlement date. MiFID II records generated automatically.
Webhook: rebalance.completed
// JavaScript SDK
const pwt = new Portfolwright({
apiKey: "sk_live_••••••••"
});
await pwt.portfolios.rebalance("pf_3x8k2m", {
target_weights: {
"IE00B4L5Y983": 0.60,
"LU0908500753": 0.25
},
tax_method: "HIFO",
drift_threshold: 0.05
});{
"rebalance_id": "rb_7z4n9q",
"status": "completed",
"order_sequence": [{
"isin": "IE00B4L5Y983",
"exchange": "XEUR",
"side": "buy",
"quantity": 142,
"tax_lot_id": "tl_2025_03_18"
}],
"mifid_record_id": "mf_8k3p1r",
"tax_impact_eur": -312.40
}Go from signed up to first rebalance in two weeks.
API keys available in your dashboard on day one. Sandbox environment with test portfolios included. Dedicated integration engineer assigned to your team.
Used by platforms who tried building it first
"We connected to Euronext Paris, Deutsche Börse Xetra, and Nasdaq Nordic through a single Portfolwright integration. We had been planning a six-month in-house build. The normalized order struct and webhook layer got us live in three weeks."
Erik Lindqvist
CTO, VestNord — Nordic retail investment platform
"MiFID II Article 25 best-execution records were blocking our compliance sign-off for months. Portfolwright generates them automatically on every order leg — execution venue, venue selection rationale, price achieved, timestamp. Our compliance team closed the weekly review in 40 minutes, down from a full day."
Sophie Marsh
Head of Engineering, Mira Invest — UK retail platform
Rebalancing events processed
European exchanges in production
Uptime SLA on Growth tier