How Ramp engineers accelerate code review with Codex

At Ramp, engineers are using Codex with GPT‑5.5 to accelerate code review and develop internal agentic tooling, helping teams get substantive pull request feedback in minutes instead of hours. Thanks to its reasoning capabilities, Codex with GPT‑5.5 is uniquely able to reduce the amount of manual, hands-on work they’d otherwise have to do.

Ramp’s AI Developer Experience team is using Codex to improve software development velocity and code quality.

“Codex code review is industry gold standard. We’ve been relying on it for a long time here at Ramp,” explains Austin Ray, who leads AI DevEx. “It’s incredible, and our engineers ask for it by name. They look forward to its comments on every PR, and it’s become a mandatory part of a lot of code review flows.”

And that’s what Ray recommends for other leaders: Focus on the hands-on experience and real-world results.

Ray is also using Codex to support the development of On-Call Assistant, an agentic tool that takes on most of the burden for Ramp engineers during on-call rotations.

With Codex, Ray can depend on its “incredibly adept” reasoning capabilities to support development. As a result, On-Call Assistant has become significantly faster to build, and Ray is more confident about every improvement shipped.

Codex is changing how fast Ramp engineers can work and giving them the resources to support even greater ambitions. For Ray, this indicates a new way to think of engineering as a whole.

Ramp engineers who used to wait hours for a first review can now get substantive feedback from Codex in minutes. Codex stands apart from other tools because it deeply reasons against the codebase, resulting in what Ray describes as “a level of thoroughness that most human reviewers don’t have time for.”

Codex matches this depth with an experience that, Ray says, “meets engineers where they are.” Engineers who prefer to work close to the metal can work from the CLI, and the Codex app provides visual cues, utilities, and additional features for those who want them. Ray, typically a CLI user, felt drawn to the app. “It feels like the app shepherds you toward higher productivity in your engineering workflows,” Ray says.

“On call is hard,” Ray explains. “We have a lot of business logic, domain knowledge, and heavy incidents. You have to keep a ton of things in context and reason through a lot of complexity.”