This quarter, we’re excited to spotlight Matthew Bain, Distinguished Engineer and Executive Director at Morgan Stanley, Lead CALM Maintainer, and a member of FINOS’s Technical Oversight Committee (TOC). A long-time FINOS contributor, Matt also maintains the TraderX project, is a co-lead of the DevOps Automation SIG and the working group lead for Architecture as Code, epitomizing sustained leadership across the FINOS ecosystem. Matt was also the recipient of the Coach Award at OSFF London 2025.

Based in London, Matt brings over 20 years of experience building trading systems, data platforms, and developer tooling in financial services. When he’s not working on open source, you’ll often find him watching cricket at The Oval.

CALM: A Community-Driven FINOS Success Story

Led by Matthew Bain, the Common Architecture Language Model (CALM) began as a community-driven effort within the DevOps Automation SIG, emerging from the Architecture as Code Working Group. Matt’s early work focused on solving a shared industry challenge: how to describe and evolve system architectures in an efficient, consistent and verifiable way.

As interest grew, Matt helped guide CALM’s evolution into a formal FINOS project, working closely with the community and FINOS staff to establish open governance and sustained collaboration. In this role, he led as a point of connection, maintaining momentum, increasing visibility and ensuring the project remained community led as it scaled under the FINOS umbrella.

Since then, CALM has continued to mature. Under Matt’s leadership, the project delivered a v1 release in August 2025, formed a dedicated core team of maintainers & contributors and built visibility through multiple Open Source in Finance Forum (OSFF) presentations in both London and New York. In parallel, contributors developed a series of trainings and tutorials, making CALM easier to understand, adopt, and apply in practice. Today, CALM is supported by maintainers and contributors from multiple firms, with active participation from financial services organizations across the industry.

Why CALM Is Important

CALM ensures that architectural decisions are consistently applied and easily auditable.

As financial institutions modernize increasingly complex and regulated technology environments, it can be challenging for teams to describe architectures, and how they evolve, in a consistent way that supports understanding by both humans and Agentic engineers and architects. CALM addresses this by providing a common language to architectural lifecycle mapping, improving clarity and collaboration and is proving instrumental in delivering consistency and predictability with Agentic AI tools.

Get Involved with CALM

CALM has recently launched its 2026 Project Roadmap, outlining the next phase of growth and deeper cross-industry participation.

Interested in joining the CALM community?

• Read the CALM 2026 Roadmap to see what’s ahead
• Join an upcoming CALM monthly call and help shape the project’s next phase
• Attend Architecture as Code office hours - Matt regularly attends and welcomes questions
• Explore CALM trainings and tutorials to get started

Open source in financial services succeeds when communities build together. CALM’s journey and Matthew Bain’s leadership within it are strong examples of that collaboration in action.