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Selected work

62 fintech platforms. Three we'll talk about in detail.

Most of our work is behind NDAs we take seriously. Below: three deep cases where founders let us tell the story, plus a short list of everyone else.

62
Platforms shipped
$4.1B
Annual volume
19
SOC 2 reports landed
94%
Repeat clients
CASE 01 / LENDINGSeries B14 months2024–2025

Halcyon Lending: One ledger replaced 14 systems

!
The Challenge
Reconciliation across 14 disparate systems took 6 hours daily. Origination, servicing, three warehouses, two collection platforms, a homegrown loan tape, and a Google Sheet — each reporting different numbers. SOC 2 had 11 exceptions. Series B diligence was 8 weeks out.
+
How We Helped
Spent sprint one mapping data lineage. By week four had a one-page diagram the auditor signed off on. Built an event-sourced canonical ledger on Postgres + Temporal. Migrated 2.4M historical entries. By week eight, loans originated against the new ledger.
✓
The Impact
6-hour batch became a 4-minute streaming job. Google Sheet was deprecated. Zero SOC 2 findings on next audit. Series B closed at a higher valuation, with the diligence team calling the architecture "unusually mature." $2.4M annualized ops savings.
Before & After
Source systems14 → 1
Reconciliation6h 12m → 4m
Unreconciled / EOM$340k → $0
Ops headcount4 FTE → 0.5 FTE
SOC 2 findings11 → 0
Annualized savings$2.4M

"They walked in, found the four queries the entire company depended on, and built a system around them. We closed our Series B with the diligence team calling our architecture 'unusually mature.'"

MW
Marcus Whitfield
VP Engineering · Halcyon Lending
CASE 02 / PAYMENTSSeries A9 weeks2025

Parallel Pay: Real-time payments shipped in 9 weeks

!
The Challenge
Beautiful card product, board mandate to ship RTP before the next pricing round. Existing payments stack was three contractors, two vendors, and a refactor that had been "two weeks out" for six months. No clear ownership.
+
How We Helped
Absorbed the active work, killed the refactor, and shipped against a clean orchestration layer on Go + TigerBeetle + Temporal. Idempotency throughout, multi-rail routing, observability dashboards before traffic.
✓
The Impact
RTP live in week nine. Month one cleared $410M with zero operational incidents, zero reversals, two compliance escalations (resolved in the system, not in Slack). 99.99% SLA hit on settlement.
RTP Volume · first 12 weeks
$410M
Month one cleared, zero reversals
W1 · $4MW6 · $128MW12 · $410M
9wk
To prod
0
Reversals
99.99%
SLA

"Beltline replaced four contractors and a planning offsite with one team and a Notion doc. We shipped real-time payments in nine weeks."

DT
Diana Tang
CTO · Parallel Pay
CASE 03 / COMPLIANCESeries C21 days2025–2026

Atlas Treasury: SOC 2 saved three weeks before close

!
The Challenge
21 days from SOC 2 Type II close. 38 open exceptions, 2 missing controls, broken evidence pipeline, and an auditor patiently asking when the pipeline would actually pipe evidence. Internal team had been working weekends for two months.
+
How We Helped
Two senior engineers deployed. Mapped every exception to a one-line fix or a one-paragraph response. Rebuilt the control evidence pipeline against their actual systems. Prepped the auditor packet from scratch.
✓
The Impact
Audit closed on schedule with zero findings. Atlas now uses the same playbook for ISO 27001. The auditor described the controls as "the cleanest she'd seen in a year."
21-Day Recovery
D1Diagnose
✓
D4Triage
✓
D8Pipeline rebuild
✓
D11Remediate
✓
D15Evidence
✓
D21Audit closed · 0 findings

"They saved our SOC 2. More importantly, they made the next one easy. The auditor described the controls as 'the cleanest she'd seen in a year.'"

AT
Aisha Tran
Head of Compliance · Atlas Treasury
More engagements

More of the work we can talk about

A short selection — the cases not behind tighter NDAs.

PAYMENTS2024

Ledgermint

Multi-tenant card-issuing platform for vertical SaaS. Shipped on Lithic + custom orchestration. Powers $1.2B in annual GMV today.

14 weeks · 4 ppl→ $1.2B GMV
BANKING2024

Northbound Capital

Sponsor-bank diligence packet, BaaS architecture, and the 200-page operating procedure manual. Approved first review.

8 weeks · 2 ppl→ Bank approved
WEALTH2024

Sixth & Co.

RIA-facing portfolio management console, billing engine, and the migration off Tamarac. Hosts $4.2B AUM live.

22 weeks · 5 ppl→ $4.2B AUM
TREASURY2023

Modulus FX

FX desk + cross-border payouts for a vertical-SaaS embedded finance product. Killed three vendors in the process. 47bps saved per transaction.

18 weeks · 4 ppl→ 47bps saved
LENDING2023

Junction Bank

SMB working-capital origination — application to funding in < 90 seconds, full underwriting audit trail. 4× conversion lift.

16 weeks · 3 ppl→ 4× conversion
PAYMENTS2023

Anchor Payouts

Mass-payout engine for a marketplace. 180k payees, four countries, two banking partners, one ledger. 99.97% on-time delivery.

11 weeks · 3 ppl→ 99.97% on-time
Across every engagement, since 2017

The work, added up

62
Platforms shipped
$4.1B
Annual volume on our rails
19
SOC 2 reports landed
0
Audits failed
31
Funding-round diligence calls
94%
Clients who came back
On the record

What founders say after we leave

"The only consultancy I've worked with that turned down scope. They cut our roadmap in half and our velocity tripled."

RM
Roberto Mendoza
CEO · Modulus FX

"I've worked with the big names. None of them get fintech the way Beltline does. None of them ship like Beltline does."

SK
Sarah Kowalski
CTO · Series C lending platform

"Beltline sat in our Series A diligence call and answered every technical question better than our CTO would have. He hired one of them three months later."

JL
James Liu
Founder · Embedded payouts startup

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