* The unified API saves us from building and maintaining dozens of brittle integrations

* Excellent coverage and fast connector delivery—new vendors get added quickly.

* Support is responsive and knowledgeable; they don’t hand-wave.

* Great observability—logs, retries, and error surfaces make debugging painless. Review collected by and hosted on G2.com.

* Great API, but the SDK isn’t there yet: inconsistent naming, limited helpers, and outdated examples increase dev time

* Would love field-level selection and a clear ‘field matrix’ across ATSs so we know exactly what comes back. Review collected by and hosted on G2.com.

It's hard to think of any upside if I'm honest. Review collected by and hosted on G2.com.

You cannot market this feature because none of the integrations are ready to be used. As the customer, you are expected to QA every integration yourself.

Also: Their marketing website lists integrations that are not available.

Also: Many of their integrations do not contain data (such as Pay) which was flagged by us during the sales process as important.

Also: They only fix integrations once you ask them to - which there is no SLA for.

Also: You get very little or no testing credentials to any HRIS providers unless you're paying them upwards of £70,000 a year.

This renders the integration worthless, as it cannot be relied on to provide our clients with a good experience.

I have quotes from StackOne to evidence every point that is raised above. Review collected by and hosted on G2.com.

StackOne has been very willing to provide support when we ran into roadblocks with an issue, and has also been willing to jump on a call with our clients to be a technical resource during specific issues that arise during the integration setup. Their willingness to do this and be flexible is what I like most about StackOne. Review collected by and hosted on G2.com.

There are a few key features that would be nice to have such as the ability to filter out records from integrations. Sometimes we run into timeout issues/errors and that has also been a challenge. I wish RaaS was supported over more partners other than WorkDay. I don't have an issue with StackOne as a platform at all, but there are a few features that would make my job easier. Review collected by and hosted on G2.com.

StackOne’s unified API dramatically simplified our HRIS integrations. It's one integration to rule them all. And their team bent over backwards to build custom connectors on our timeline. The real-time, no-data-store architecture means we can launch new integrations in weeks, not months, and their AI-assisted field-mapping UI cut our mapping effort in half. The dedicated solutions engineer and Slack channel support made troubleshooting and governance friction nearly disappear. Review collected by and hosted on G2.com.

A few corner-case fields required manual tweaks in the UI. Otherwise, their transparency and responsiveness have kept us moving forward. Review collected by and hosted on G2.com.

The whole process of integrating StackOne into our product was smooth from start to finish. The API is polished with great documentation and we received fantastic support during the development process. The StackOne team was always available to take questions in a timely manor and also made amendments their side if needs be. The aggerate API they offered had all the endpoints we needed to complete our integration. StackOne also provide good debugging tools within their product that help you identity issues that maybe occurring with the 3rd party APIs. Review collected by and hosted on G2.com.

Thats nothing to add here really as the product did what we needed it to do. Review collected by and hosted on G2.com.

StackOne has been instrumental in accelerating our product roadmap.

Building and maintaining in-house integrations for the numerous ATS, LMS and HRIS platforms our customers use would be a huge drain on our Engineering resources. StackOne's unified API has abstracted all that complexity away.

The API is robust and the documentation is very clear. The platform well designed underpinned with a thoughtful User Experience.

What's stood out to me having used similar products has been the team's responsiveness and collaborative approach. They feel like an extension of our own team which is super rare for a vendor. Review collected by and hosted on G2.com.

No much to contribute to the dislikes there are some more niche integrations that are less mature than the core ones.

However the team has been transparent about this and has been proactive in working with us to address any edge cases we've encountered.

It hasn't been blocker for us. Review collected by and hosted on G2.com.

We work with StackOne from a partner perspective, collaborating closely on integrating connectors that help make our clients' lives easier. Over time, we’ve built an amazing rapport with the team, and it’s been a genuinely positive experience throughout.

What stands out most is their willingness to go the extra mile. The StackOne team is always available when we have questions or need guidance, and their responsiveness and technical expertise have been invaluable in getting projects across the finish line. Review collected by and hosted on G2.com.

There’s honestly not much to critique—they’re great at what they do and truly feel like an extension of our own team. It’s rare to find a partnership that feels this seamless and supportive. Review collected by and hosted on G2.com.

Well designed unified API to 3rd party systems,

Practical and complete documentation,

Quick reaction to changes in 3rd party systems and reported issues Review collected by and hosted on G2.com.

Error handling and reporting is not unified

Customization options are limited Review collected by and hosted on G2.com.

The APIs and elements are thoughtfully designed. Their unified structure allows you to integrate with almost anything once you have completed a single integration. This significantly accelerates development and makes it much easier to add new integrations based on client needs. Review collected by and hosted on G2.com.

Since it is a vert fast paced growth company , sometimes things are not working as expected and fixes might take a while Review collected by and hosted on G2.com.

What we like best about StackOne is its ability to simplify complex LMS integrations. It saves our team significant time and effort by providing reliable, consistent access to data across multiple LMS platforms. The platform is stable, well-documented, and the support team is responsive and knowledgeable. Review collected by and hosted on G2.com.

not much, they are always helpful and the documentation is helpful Review collected by and hosted on G2.com.