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deal.II

DEVOPS
Velocity2.5

C++ finite element library for solving partial differential equations

dealii.org ↗

deal.II ships one big finite-element release a year, then patches it twice

finite-elementsscientific-computingannual-releasepoint-releasesopen-sourcecontributor-growth
◆Current state
deal.II is on a steady annual major-release rhythm — 9.6 in late 2024, 9.7 in July 2025, 9.8 in August 2026 — with one or two bug-fix point releases filling each gap. Its GitHub release notes are deliberately thin: each one links out to a generated changes-between-versions page and spends its body on contributor credits. What the feed does show directly is the shape of the project, including a release-candidate train that runs about two weeks before each major.
◆Where it's heading
The contributor roster is the signal these notes carry best, and it is growing: 9.8.0 alone credits roughly two dozen first-time contributors against a recurring core of about sixty. Point releases stay narrow and mechanical — MSVC and C++20 compatibility, MatrixFree face handling, Trilinos/Tpetra fixes — which suggests release engineering is stable enough that regressions surface in a predictable band. Nothing in the feed indicates a change of direction; this is a mature library compounding.
◆Prediction
Based on the 9.6 and 9.7 patterns, expect a 9.8.1 within roughly two months carrying compiler-compatibility and MatrixFree fixes, and the next major in mid-2027 preceded by a short rc1-through-rc4 train. The release notes themselves are unlikely to get more detailed given how consistently they defer to the external changelog.

◆Recent moves

  1. 21h ago

    deal.II version 9.8.0

    The annual major release, landing about twelve and a half months after 9.7.0 and holding the cadence. The published notes list contributors rather than changes and point to a generated changes-between-versions page, so the scope is not visible in the feed itself; the two dozen first-time contributors credited are the one concrete detail it does carry.

    View source ↗
  2. 10mo ago

    deal.II 9.7.1 fixes MSVC C++20 and MatrixFree 1D faces

    A four-fix point release two months after 9.7.0, covering MSVC C++20 compatibility, MatrixOut defaults, an FESystem line-orientation bug and 1D face handling in MatrixFree. This is the narrow compiler-and-edge-case band where deal.II regressions consistently land.

    View source ↗
  3. 1y ago

    deal.II version 9.7.0

    The 2025 major release, closing a release-candidate train that ran from rc1 on 11 July to rc4 the day before. As with 9.8.0, the body defers to an external changelog and credits contributors rather than enumerating changes.

    View source ↗
  4. 1y ago

    deal.II 9.7.0 release candidate 4

    The final pre-release, cut one day before 9.7.0 shipped. Carries no notes beyond its own designation — the rc train exists to gather downstream build reports, not to document changes.

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  5. 1y ago

    deal.II 9.7.0 release candidate 3

    Third candidate in the 9.7.0 train, three days after rc2 and four before the release. Contentless by design, like the rest of the series.

    View source ↗
  6. 1y ago

    deal.II 9.7.0 release candidate 2

    Second candidate in the 9.7.0 train, a week after rc1. The tightening interval between candidates — seven days, then three, then one — is the only information the sequence conveys.

    View source ↗