I strongly disagree with quickly sunsetting hibernate 5 or deciding on it so quickly. It's already split out and works without the build modifications that micronaut requires - ideally we want anything in our repo that's easy to maintain. We should release hibernate with support in 8.x and then evaluate what we do with Grails 9 (spring boot 5). The difference between micronaut and hibernate is that micronaut is causing a substantial amount of work that conflicts with the other dependencies and leads to a completely insecure Grails app. Hibernate hasn't had that problem. Personally, I think we should leave hibernate 5 support as optional in 9 (default to hibernate 7 in 9) because it's a major change and then remove it when we do Spring Boot 6.
For micronaut, my proposal is to release it in 8, but then do no further releases unless we have someone to support it. I'm suggesting we effectively drop support for it after the initial 8.0.x release. -James On Tue, Jun 16, 2026 at 11:34 AM Walter Duque de Estrada <[email protected]> wrote: > > Thanks for outlining the challenges with Micronaut so clearly. Rather than > moving it to a side repository immediately, I propose a phased sunsetting > strategy. I also think we should include Hibernate 5 (h5) in this exact same > plan. > > Here is my proposed path: > > Grails 8.0.x: Micronaut and h5 are kept in the build. It is uncomfortable but > manageable. We accept patches only. > > Grails 8.1.x: They are kept in the codebase historically, but are strictly > unmaintained. > > Grails 9.0.x: Micronaut and h5 are completely removed. > > This approach gives any remaining users a predictable runway while > immediately reducing our maintenance burden so we can focus on core > priorities like the Hibernate 7 migration. > > What does the team think > > Thanks, > > Walter > > > > On Jun 16, 2026, at 8:06 AM, James Daugherty <[email protected]> wrote: > > > > Hi Everyone, > > > > For the last 2 weekly meetings we have discussed the problems of > > integrating Micronaut & Spring. Both James Fredley & I have spent a > > significant amount of time ensuring Micronaut continues to work with > > Grails. While we have a solution for Grails 8, we don't think we can > > continue this support without a champion to help in this area. Here > > are the problems we've encountered: > > > > 1. Micronaut & Spring are updating dependencies at a different pace. > > This is really our core issue. For example, in Spring Boot 3.5.x > > Netty was updated to 4.1.x, while Micronaut jumped to 4.2.x. These > > version mismatches introduce hard incompatibilities which makes us > > choose which framework to prefer. Because Spring chose the lower > > version, we were forced to choose Netty 4.1.x, which meant that the > > Micronaut version had to be kept at a lower version. During 8.0's > > development, this was even more extreme due to the Micronaut 5.x > > development. > > > > 2. The downgrading of dependencies means CVEs in our dependent > > libraries often will exist and we will be unable to update. This is a > > huge blocker for us. We can't release insecure software. Without > > members on either the Micronaut or Spring teams, we can't really help > > resolve these issues. Micronaut has been helpful in updating > > libraries when we request, but we don't think it's reasonable to ask > > them to downgrade - we're not involved in their framework development. > > > > 3. Micronaut made the decision to jump all the way to Java 25 in > > Micronaut 5, even though 21 is still supported. Spring made the > > decision to support all the way back to 21. We had discussed going to > > 25, but we wanted to choose the minimum JVM version that would be > > supported for the life expectancy of Grails 8 (so we chose 21). This > > means that the micronaut portions of our build have to be built with > > Java 25, while the rest is built with Java 21. This is another huge > > issue for us because the ASF Security team requires reproducible > > builds. Which means a significant amount of work had to go into our > > verification process to support this divergence. > > > > 4. We have not seen significant contributions to the Micronaut support > > in Grails. Only James Fredley & James Daugherty have been evolving > > it. Without a champion to help with these problems, we are spending > > too much of our time on Micronaut and not enough on other core > > priorities (i.e. Hibernate 7). > > > > 5. We believe there are a low number of users still using the > > Micronaut support and thus the effort to continue this support is > > higher than the reward. > > > > This email is meant to start a wider discussion: we want to move the > > micronaut support into a side repository. If we can find a champion > > to help maintain it, then we can keep publishing it separate from > > Grails. Otherwise, we will eventually archive that integration and > > abandon it. > > > > -James >
