Banking Software Development

Software for banks and credit unions: cores, ledgers, payments, lending, and digital channels, built by senior engineers with the controls examiners expect.
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Definition

What is banking software development?

Banking software development covers the systems a bank runs on: the core and ledger that hold accounts and balances, the payment rails that move money, loan origination and servicing, the digital channels customers see, and the reporting that goes to regulators and the board. BD Emerson designs, builds, and integrates these systems for banks and credit unions, working with the core you have or replacing pieces of it in stages. Every build ships with the access controls, audit trails, and documentation your examiners will ask for.

Services

What banking software services are included?

Core and ledger engineering
Payments integration
Loan origination and servicing
Digital banking channels
Regulatory reporting and data
Core vendor integration

Core and ledger engineering

We build account, balance, and posting logic to bank standards: double-entry ledgers, idempotent postings, and end-of-day reconciliation. We extend the core you run, build around its limits, or replace it in stages when the numbers justify a move.

Payments integration

We connect to the rails banks use: ACH, wires, RTP, FedNow, and card networks. We build origination, settlement, and exception handling for each rail, and we treat cutoff windows, returns, and reversals as designed paths rather than edge cases.

Loan origination and servicing

We build origination, underwriting workflow, servicing, and collections around your credit policy rather than a vendor's assumptions. Lending is where banks differ most, so it is where custom software most often earns its cost.

Digital banking channels

We build online and mobile banking connected to the core through clean APIs: real-time balances, transfers, and payments for retail and business customers. You control the roadmap instead of waiting on a vendor release cycle.

Regulatory reporting and data

We build the data layer behind call reports, BSA and AML monitoring, and board reporting, then the reconciliation on top of it, so the numbers your regulators see match the ledger every period.

Core vendor integration

We integrate with the incumbent core landscape: FIS, Fiserv, and Jack Henry systems, plus the processors and fintech tools around them. We work through their APIs and file interfaces, and we resell nothing, so the integration advice stays ours.

Our approach

Our approach

01

Buy the commodity, build the difference

Banks should buy commodity capability and build only what sets them apart. We put that split in writing before the first sprint: which capabilities a vendor already covers well, which ones deserve custom work, and what each path costs.

02

Design the ledger and the seams first

Banking systems fail where they meet, at postings, cutoffs, and reconciliation points. We design the account model, integration contracts, and failure handling before feature code, because those decisions are the expensive ones to reverse.

03

Prove it against the old system

A new system runs in parallel with the one it replaces until the outputs agree. We reconcile at the transaction and balance level on live data, and cutover happens only when the evidence shows the two systems match.

04

Hand over a system your team runs

Delivery ends with your people operating the platform: documentation, runbooks, monitoring, and the audit evidence collected during the build. We stay available for the next phase, and you keep every artifact either way.

contact us

Planning a core replacement or a new banking build?

Bring the core you are working around, the rail you need to reach, or the build vs buy decision on your desk. An engineer will walk through it with you and tell you what we would do, including when the answer is to buy.

Our Advantage

Why BD Emerson for banking software

Senior engineers end to end

The engineers who scope the work build it, and the people in the first call stay on the build. Your ledger and payments logic is not handed to a rotating delivery bench after signing.

Independent of the core vendors

We resell nothing and take no margin from FIS, Fiserv, Jack Henry, or anyone else. When we recommend buying instead of building, the advice costs us work, and we give it anyway.

Compliance is in the build

GLBA safeguards, access controls, and audit evidence are designed in from the first sprint rather than retrofitted before an exam. BD Emerson performs SOC 2 examinations through its licensed CPA attest arm, so we build to the standard the evidence gets judged by.

How We Work

How we deliver banking software

Every engagement runs the same delivery model, from a single payments integration to a staged core replacement. Each step ends in an artifact your bank keeps: an inventory, a written recommendation, a design, or a reconciled cutover.
Reviews

What our customers say

Great consulting firms for scaling security, compliance, and appsec.

Outstanding partner in Technical and Cyber Due Diligence

Appsec maturity and application hardening.

BD Emerson helped us simplfiy our compliance management.

BD Emerson did such a phenomenal job. What started as privacy support quickly became a full partnership across compliance, engineering, and even business operations. They’re embedded with our team. They understand our product. They move fast. They’re simply invaluable.

Adam Ben Jacobs

CTO @ OneStep GPS

Great consulting firms for scaling security, compliance, and appsec.

Outstanding partner in Technical and Cyber Due Diligence

Appsec maturity and application hardening.

BD Emerson helped us simplfiy our compliance management.

BD Emerson did such a phenomenal job. What started as privacy support quickly became a full partnership across compliance, engineering, and even business operations. They’re embedded with our team. They understand our product. They move fast. They’re simply invaluable.

Adam Ben Jacobs

CTO @ OneStep GPS

We had a hard time finding the right company to partner with in support of our compliance journey. Some vendors sell the idea that they do the work, but then you end up doing everything. The ambiguity is what killed our last project. BD Emerson’s team has such great technical knowledge and understands the standard so well that they made us comfortable with moving fast. This has led to us closing major enterprise customers that were previously out of reach because of security and compliance.

Tom Watkins

CEO @ AMI AssetTrack

Lead an enterprise initiative to overhaul the organization's technology stack from ecommerce, corporate tech, and corporate security.

Supported ISO 42001 exercise and served as internal auditor.

Rubrik's privacy and compliance team began with the backbone of BD Emerson. BD Emerson supported building out the privacy program, GRC (ISO 27001, SOC 2, CMMC, FedRAMP), and the appsec function.

We needed a partner who could move quickly, without sacrificing precision. BD Emerson brought the expertise, structure, and speed we were looking for. Their team became an extension of ours, embedding themselves across the organization, guiding us step by step, and giving us confidence in areas we hadn’t tackled before. The internal audit they conducted was so detailed that even the external auditors called it out. Achieving ISO 27001 with zero nonconformities says everything you need to know about the quality of the partnership.

Walid Souilem

CTO @ FGI Worldwide

We had a hard time finding the right company to partner with in support of our compliance journey. Some vendors sell the idea that they do the work, but then you end up doing everything. The ambiguity is what killed our last project. BD Emerson’s team has such great technical knowledge and understands the standard so well that they made us comfortable with moving fast. This has led to us closing major enterprise customers that were previously out of reach because of security and compliance.

Tom Watkins

CEO @ AMI AssetTrack

Lead an enterprise initiative to overhaul the organization's technology stack from ecommerce, corporate tech, and corporate security.

Supported ISO 42001 exercise and served as internal auditor.

Rubrik's privacy and compliance team began with the backbone of BD Emerson. BD Emerson supported building out the privacy program, GRC (ISO 27001, SOC 2, CMMC, FedRAMP), and the appsec function.

We needed a partner who could move quickly, without sacrificing precision. BD Emerson brought the expertise, structure, and speed we were looking for. Their team became an extension of ours, embedding themselves across the organization, guiding us step by step, and giving us confidence in areas we hadn’t tackled before. The internal audit they conducted was so detailed that even the external auditors called it out. Achieving ISO 27001 with zero nonconformities says everything you need to know about the quality of the partnership.

Walid Souilem

CTO @ FGI Worldwide

BD Emerson didn’t just help us meet our compliance goals; they integrated security and privacy into the core of our operations. I highly recommend BD Emerson to anyone seeking SOC 2 or GDPR compliance, or simply looking to enhance their security team and boost customer trust in their product and services. Their dedication and expertise have been invaluable to our success.

Padraig Reilly

CEO, Boxcore

BD Emerson understood our business requirements and worked side-by-side with us. The policies and controls we developed together not only meet compliance standards but improve how we operate day to day.

Matt Meierdierks

IT Manager, Lincoln Industries

From day one, BD Emerson brought urgency, clarity, and a sharp understanding of what truly matters to our business — earning and keeping customer trust. They went beyond helping us meet compliance requirements; they helped build a foundation for secure, scalable growth. That kind of partnership is rare.

Jason Marker

CEO @ LifeLenz

BD Emerson didn’t just help us pass an audit—they helped us build a sustainable culture of security.

Alexey Indeev

CTO Spare

BD Emerson was essential in helping our company navigate the daunting process of leveling up our security infrastructure. BD Emerson’s impressive expertise and confidence throughout the process helped our team exceed HIPAA and SOC 2 Type 1 standards quickly, distilling what can be an overwhelming process into a streamlined, organized effort. From day one they began adding value and getting us on course. With their help we delivered on a massive security overhaul with both extreme efficiency and thorough attention to details. Because of BD Emerson’s support, we’ve increased our clients’ trust in Titan Intake and the life-changing work it accomplishes for those seeking specialist referrals.

Patrick Bruce

CEO, Titan Intake

BD Emerson didn’t just help us meet our compliance goals; they integrated security and privacy into the core of our operations. I highly recommend BD Emerson to anyone seeking SOC 2 or GDPR compliance, or simply looking to enhance their security team and boost customer trust in their product and services. Their dedication and expertise have been invaluable to our success.

Padraig Reilly

CEO, Boxcore

BD Emerson understood our business requirements and worked side-by-side with us. The policies and controls we developed together not only meet compliance standards but improve how we operate day to day.

Matt Meierdierks

IT Manager, Lincoln Industries

From day one, BD Emerson brought urgency, clarity, and a sharp understanding of what truly matters to our business — earning and keeping customer trust. They went beyond helping us meet compliance requirements; they helped build a foundation for secure, scalable growth. That kind of partnership is rare.

Jason Marker

CEO @ LifeLenz

BD Emerson didn’t just help us pass an audit—they helped us build a sustainable culture of security.

Alexey Indeev

CTO Spare

BD Emerson was essential in helping our company navigate the daunting process of leveling up our security infrastructure. BD Emerson’s impressive expertise and confidence throughout the process helped our team exceed HIPAA and SOC 2 Type 1 standards quickly, distilling what can be an overwhelming process into a streamlined, organized effort. From day one they began adding value and getting us on course. With their help we delivered on a massive security overhaul with both extreme efficiency and thorough attention to details. Because of BD Emerson’s support, we’ve increased our clients’ trust in Titan Intake and the life-changing work it accomplishes for those seeking specialist referrals.

Patrick Bruce

CEO, Titan Intake

Certificates

Our accreditations

At BD Emerson, we believe that our team's extensive certifications not only set us apart but also ensure that we provide the highest level of service to our clients.
FAQ

Frequently asked questions

Should a bank build or buy its core system?

How do you replace a legacy ledger without breaking balances?

What do examiners ask about custom software?

What drives the timeline on a banking software build?

Can you work with our existing core vendor?

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