Fit: PartialCore overlap exists; named gaps need replacing or rebuilding.Fit is not feature parity.ATier ANo paid feature gates in the self-run editionMIT LicenseA short and simple permissive license with conditions only requiring preservation of copyright and license notices. Licensed works, modifications, and larger works may be distributed under different terms and without source code.MayCommercial useModificationDistributionPrivate useMustLicense and copyright noticeNoLiabilityWarrantySummary from GitHub's choosealicense.comSelf-hostable: yesYou can run it on your own server.
Documentation/wiki use case covered with book/chapter/page hierarchy, roles, API and export options; validate Confluence macros/integrations and rebuild unsupported content.
Fit: PartialCore overlap exists; named gaps need replacing or rebuilding.Fit is not feature parity.CTier CDaily-workflow features need a paid editionGNU Affero General Public License v3.0Permissions of this strongest copyleft license are conditioned on making available complete source code of licensed works and modifications, which include larger works using a licensed work, under the same license. Copyright and license notices must be preserved. Contributors provide an express grant of patent rights. When a modified version is used to provide a service over a network, the complete source code of the modified version must be made available.MayCommercial useModificationDistributionPatent usePrivate useMustLicense and copyright noticeState changesDisclose sourceNetwork use is distributionSame licenseNoLiabilityWarrantySummary from GitHub's choosealicense.comSelf-hostable: yesYou can run it on your own server.
Confluence HTML space ZIP importer is Business-gated; docs claim formatting, hierarchy, internal links, images/attachments and Draw.io diagrams preserved. Test macros and integrations separately.
Source-available or unresolved
Kept apart: these are not open source by the OSI definition, or their license scope is not settled.
Fit: PartialCore overlap exists; named gaps need replacing or rebuilding.Fit is not feature parity.STier SSource-available license, not OSIBUSL 1.1 (custom license)Not a standard license, so GitHub's license summaries don't cover it. Read the project's license text before relying on it.Self-hostable: yesYou can run it on your own server.
Knowledge-base replacement candidate under BSL rather than OSS; Confluence importer listed among on-premise features but exact paid-tier placement not verified. API export capabilities documented.
Fit: Different approachSolves the same job differently; plan a redesign, not a copy.Fit is not feature parity.UTier ULicense or parity scope unresolvedMIT LicenseA short and simple permissive license with conditions only requiring preservation of copyright and license notices. Licensed works, modifications, and larger works may be distributed under different terms and without source code.MayCommercial useModificationDistributionPrivate useMustLicense and copyright noticeNoLiabilityWarrantySummary from GitHub's choosealicense.comMozilla Public License 2.0Permissions of this weak copyleft license are conditioned on making available source code of licensed files and modifications of those files under the same license (or in certain cases, one of the GNU licenses). Copyright and license notices must be preserved. Contributors provide an express grant of patent rights. However, a larger work using the licensed work may be distributed under different terms and without source code for files added in the larger work.MayCommercial useModificationDistributionPatent usePrivate useMustDisclose sourceLicense and copyright noticeSame license (file)NoLiabilityTrademark useWarrantySummary from GitHub's choosealicense.comAFFiNE EE (custom license)Not a standard license, so GitHub's license summaries don't cover it. Read the project's license text before relying on it.Self-hostable: yesYou can run it on your own server.
Docs/whiteboards for shared knowledge; verify EE/CE license scope and procurement before production. Migration compatibility not independently tested.
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MIT License A short and simple permissive license with conditions only requiring preservation of copyright and license notices. Licensed works, modifications, and larger works may be distributed under different terms and without source code. May Commercial useModificationDistributionPrivate use Must License and copyright notice No LiabilityWarranty Summary from GitHub's choosealicense.com Self-hostable: yesYou can run it on your own server. 
