Calamos Investments Catches Missing Custodian Files with Files.com Before the Trading Day Starts

Calamos Investments is a global asset manager headquartered in Naperville, Illinois, with more than $50 billion in assets under management. It is the largest US manager of convertible securities and one of the country's largest liquid-alternatives providers, running strategies through mutual funds, ETFs, closed-end funds and UCITS vehicles for institutional and individual clients worldwide.

That product range has an operational consequence. Calamos funds trade against NYSE, Canadian, Irish, Luxembourg and UCITS market calendars, and every one of them runs on a daily cycle of files: NAVs, holdings, shadow accounting and trade data arriving overnight from between 60 and 100 custodians and data vendors. The firm's start of day depends on those files showing up.

A Missing File Makes No Sound

Calamos ran its vendor-data operation on a file-triggered architecture. ActiveBatch, the firm's batch scheduler, watched the folder where vendor files landed and fired hundreds of jobs the moment the right file appeared. The architecture had one blind spot, and it was the one that mattered most: a file that never arrives produces no event. No trigger fires, no job runs, and no error is thrown. The gap surfaced only when someone discovered that a business process had not run.

“Since we're file-trigger based most of the time, if the file doesn't come in, it never triggers our job.”

The files this happened to were not incidental. Start-of-day and end-of-day NAV and shadow accounting files from custodians carry regulatory deadlines, and the firm's investment decisions run on the same data.

“We also make investment decisions on that data too, so if the data isn't there at the right time, there could be a situation where, for example, there appears to be cash here, but maybe there's not cash there because the file hasn't been updated.”

The timing made it worse. Custodian files land in the early morning hours, while the team is asleep. By the time anyone noticed a gap, the custodian's own window for redelivering the file had often closed, and the miss carried into the trading day.

A Second Job to Watch the First

The problem was known, and it survived because every available fix lived outside the layer it was watching. Detecting absence in ActiveBatch meant building a second job whose only purpose was to check whether the first one ran. The data engineering team had also bolted on its own SLA trackers in Databricks, checking whether files had reached storage and opening tickets when they hadn't. Files carried no record of who owned them or which vendor contact to chase, so even a detected miss started with backtracking.

And any schedule-based check had to know when not to expect a file. Markets close on different days in each of the five geographies Calamos operates across. Some close for half days. Some vendors follow calendars of their own that match no country's holidays. A naive check that expected a file every day at the same hour would be wrong dozens of days a year, paging an eight-person on-call rotation for files that were never due.

What the fix had to do was clear. Write down, per feed, what correct delivery looks like: which files, on which path, by when, in what shape. Evaluate every window against that definition. Know the difference between a miss and a holiday, across five market calendars. And put the alert in front of both the on-call engineer and the vendor while redelivery was still possible. Calamos selected Files.com as the landing point for its vendor files, with Expectations, the platform's built-in delivery monitoring, carrying that requirement.

Delivery SLAs Defined Where the Files Land

Custodian and vendor files now land in Files.com, and the critical feeds each carry an Expectation: the folder and file pattern to watch, the deadline, and the shape the delivered files must take. When a window closes, Files.com evaluates what arrived. A file that never came is recorded as missing and opens an incident. A file that arrived in the wrong shape is recorded as invalid before any downstream job consumes it. The team scoped this deliberately, putting Expectations on the feeds that matter most rather than on everything.

Files.com custom Holiday Calendars carry the part no generic schedule could. Calamos built calendars covering NYSE, Canadian, Irish, Luxembourg and UCITS market closures, half-day early closures, and the vendor-specific calendars that follow no national holiday schedule at all. An Expectation tied to a calendar simply does not open a window on a day no file is due, so a Dublin bank holiday no longer pages an engineer in Illinois.

When a window does fail, the alert reaches the on-call rotation, and a missed Expectation can email the responsible vendor directly, naming the file, when it was expected, and who to contact. The chase that used to start with reconstructing ownership now starts with the vendor already notified.

The same evaluation validates shape on arrival. A vendor that sends a spreadsheet where a CSV was expected used to surface as a middle-of-the-night page from a broken load. Now it is flagged as an invalid delivery at intake.

Caught in the Vendor's Window, Not the Next Morning

With Expectations running against the production feeds, Calamos replaced a silence it discovered the next morning with a signal it can act on the same night.

• A missing custodian file is detected inside the vendor's own operating window, so a replacement can be requested and delivered before the start of the business day, instead of after a downstream process has already failed.
• False alerts on market holidays are gone. An Expectation tied to a holiday calendar expects nothing on days nothing is due, across all five market calendars the firm operates on.
• Malformed deliveries are caught and recorded as invalid at intake, before a downstream job runs against bad data.
• Delivery monitoring lives in the ingestion platform itself. Defining what correct delivery looks like is now a step in standing up a feed, not a second monitoring job to build and maintain alongside every feed that matters.

The File That Never Arrives Is Now an Event

For a firm where those files carry regulatory deadlines and the day's first investment decisions, that is the change Files.com made: delivery SLAs live in the ingestion layer itself, where a file that fails to arrive is something to act on, not a silence to discover the next morning.