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Addendum Tech Stack

Enterprise software development and IT outsourcing for financial services

IT Services and IT Consulting Los Angeles, California 51–200 employees Founded 2009 Privately Held

Addendum is a 51–200-person IT services firm founded in 2009, operating primarily as a staff-augmentation and custom-development shop for banking, fintech, and telecom clients. The tech stack—Java, .NET, GCP, BigQuery, and Oracle EBS—reflects a heavy concentration in backend systems and data warehousing, with active migration work moving on-premises workloads to cloud. Current hiring is engineering-heavy (22 of 37 roles) and concentrated in mid-level engineers, with geographic expansion into Eastern Europe and Central America, suggesting capacity scaling to support larger concurrent projects.

Tech Stack 56 technologies

Core StackJava .NET Playwright Postman Jira Confluence BigQuery Python GitLab GitHub Tableau Looker Terraform Power BI Angular Swagger GCP Dataform Dataflow Google Cloud Functions SQL iOS Android TOGAF Nessus Microsoft Defender Excel Oracle EBS BlackLine Spring Boot+26 more

What Addendum Is Building

◆Challenges

Automating processes
Agent-facing experience
Optimizing reconciliation systems
Improving business process efficiency
Optimizing warehouse management system
Performance improvements
Building polish market from zero
Operational issues
Data-driven decision-making
Improving business processes

▲Active Projects

Customizing intellimatch systems
Static data setup deployment
Improve agent-facing experience of international financial application
Intellimatch development and automation for reconciliation systems
System version change and migration projects
Building polish market from zero
Structured a/b testing
Central bank systems project
Enhancing data availability across custody investment solutions
Migrating on-premises functionality to gcp

Hiring Activity

Accelerating35 roles · 20 in 30d

Department

Engineering

22

Ops

3

Data

2

HR

2

Product

2

Security

2

Consulting

1

Finance

1

Seniority

Mid

21

Senior

13

Director

1

Junior

1

Manager

1

Notable leadership hires: Strategic Delivery Director

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About Addendum

Addendum provides enterprise software development, IT resource outsourcing, and consulting services to clients in financial services, banking, telecom, and government. The firm operates as a distributed team across ten countries, with headquarters in Los Angeles and significant delivery centers in Eastern Europe. Core service lines include custom development, staff augmentation, data strategy and BI, QA, and DevOps support. Active projects span reconciliation-system automation, cloud migration (GCP), and international market expansion, with a documented focus on operational efficiency and agent-facing experience improvements for large financial institutions.

HeadquartersLos Angeles, California

Company Size51–200 employees

Founded2009

Hiring MarketsPoland, Lithuania, Latvia, Germany, United Kingdom, Philippines, Mexico, Costa Rica

Frequently Asked Questions

What tech stack does Addendum use?

Primary: Java, .NET, Python, SQL, GCP (BigQuery, Dataflow, Cloud Functions), Oracle EBS. Testing/automation: Playwright, Postman. Analytics: Tableau, Looker, Power BI. Infrastructure: Terraform, GitHub/GitLab.

What is Addendum working on?

Cloud migration to GCP, reconciliation-system optimization, expanding into the Polish market, improving agent-facing experience for financial applications, and building BI/data-availability infrastructure for custody and investment solutions.