rivencraft/docs/MINECRAFT_26_3_PORT.md

# Minecraft 26.3 port status (issue #96)

Checked 2026-10-26. Minecraft Java 26.3 is the newest stable Java release with
NeoForge support. This is an engineering audit and the start of the port, **not
a claim that a 26.3 Rivencraft JAR is ready**. The 1.21.1 build remains the
release target until a separate 26.3 client and dedicated-server build passes.
The user wants both Minecraft lines maintained after the port, not a one-time
26.3 release. Gitea milestone "Dual-version support: 1.21.1 and 26.3"
tracks issues #97–#103 under parent #96.

## Version boundary

Minecraft 26.3/NeoForge uses Java 25, while Rivencraft 1.21.1 uses Java 21.
Build and publish separate artifacts; do not widen the Minecraft dependency
range of the 1.21.1 JAR. The official [26.3 release notes](https://www.minecraft.net/en-us/article/minecraft-java-edition-26-3),
[NeoForge 26.3 Maven metadata](https://maven.neoforged.net/releases/net/neoforged/neoforge/maven-metadata.xml),
[NeoForge Java 25 setting](https://github.com/neoforged/NeoForge/blob/26.3.x/gradle.properties),
and [NeoForge migration primers](https://docs.neoforged.net/primer/docs/)
are the version sources. NeoForge 26.3.0.99 is the newest listed stable build
at the time of this check.

## Dependency availability

The entries below mean that a NeoForge 26.3 version is advertised by the
project, not that its API or runtime behavior has been validated with
Rivencraft. Recheck immediately before choosing versions for a port build.

| Integration | Role in 1.21.1 | 26.3 availability | Port decision |
| --- | --- | --- | --- |
| [Dynamic Dimensions AR Edition](https://modrinth.com/mod/dynamic-dimensions-ar-edition) | Required runtime Age loading | No; 1.21.1 only | Keep it for 1.21.1. Use a Rivencraft-owned runtime-dimension backend for 26.3. |
| [bad packets](https://modrinth.com/mod/badpackets) | Declared runtime dependency; no direct Java imports in Rivencraft | No advertised 26.3 version | Determine whether the new dimension backend needs it; otherwise remove it from the 26.3 artifact. Use NeoForge's own networking for Rivencraft packets. |
| [JEI](https://modrinth.com/mod/jei) | Optional recipe/page guides | Yes | Port and test its plugin against the 26.3 API. |
| [TerraBlender](https://modrinth.com/mod/terrablender) | Optional modded biome support | Yes | Port and verify biome discovery and Age generation. |
| [Serene Seasons](https://modrinth.com/mod/serene-seasons) and [GlitchCore](https://modrinth.com/mod/glitchcore) | Optional seasons | Yes | Port and repeat the per-Age seasonal matrix. |
| [Biomes O' Plenty](https://modrinth.com/mod/biomes-o-plenty) | Optional TerraBlender test addon | Yes | Test modded biome registration and decoration. |
| [Ruins (Structure Spawning System)](https://www.curseforge.com/minecraft/mc-mods/ruins-structure-spawning-system) | Optional authored ruins integration | Yes | Port and verify its generation hooks. |
| [Create](https://modrinth.com/mod/create) / bundled Ponder | Optional scene renderer | No advertised 26.3 version | Use Rivencraft's existing legacy-animation preview fallback for this target until a compatible release exists. |
| [Immersive Portals for (Neo)Forge](https://modrinth.com/mod/immersive-portals-neoforge) | Optional live views and portal teleport integration | No advertised 26.3 version | Use the fallback portal surface and normal Rivencraft linking. Do not claim live destination views on 26.3. |

Ecliptic Seasons publishes 26.3, but Rivencraft's Ecliptic integration was
deferred and is not a replacement for the current Serene integration.

The alternatives checked for runtime Age loading do not meet the 26.3
NeoForge requirement: [upstream Dynamic Dimensions](https://github.com/TeamGalacticraft/DynamicDimensions)
and its [AR fork](https://github.com/dercodeKoenig/DynamicDimensions)
have no published 26.3 branch or artifact;
[DimLib](https://modrinth.com/mod/dimlib) is Fabric-only and stops at 1.21.1;
and [DimensionsCore](https://www.curseforge.com/minecraft/mc-mods/dimensionscore-dynamic-dimension-world-management)
currently publishes only a Forge 1.20.1 file. Mods that add fixed dimensions
or portals do not supply the arbitrary per-book runtime worlds Rivencraft
needs. This is a search result, not proof that no other project exists.

## 26.3 backend design

The 26.3 port is a **fresh-save target**. It does not need to import 1.21.1
Age worlds or migrate Dynamic Dimensions' saved registry data. The 1.21.1
artifact will continue using that library. Within 26.3, however, a created
Age must retain its identity, seed, chunks and access across save/restart.

1. Keep the existing `AgeDimensionService`/`AgeDimensionBackend` boundary.
   Implement a target-specific 26.3 backend without importing Dynamic
   Dimensions or its seed mixin. The backend contract needs registration at
   server start, create/load, unload and delete. Return a failure without
   publishing a half-created Age if any step fails.
2. At server startup, reconstruct all non-retired Ages from Rivencraft's
   `AgeRegistrySavedData` **before** players can join. For a newly bound book,
   register its unique `rivencraft:age/...` dimension and construct a
   `ServerLevel` from its authored chunk generator, dimension type and saved
   Age seed. The seed must feed chunk random state, not only `getSeed()`.
3. Register the level with the server's level map and the appropriate
   dimension registries, then synchronize the new dimension definition to
   already-connected clients before sending a travel packet. Handle a
   connecting client receiving every existing Age. Determine the minimal
   26.3 registry and network hooks from the current NeoForge source; do not
   assume `/reload` creates new running levels.
4. Initialize world border, view/simulation distance, forced chunks, spawn
   settings, per-Age data storage and tick/save lifecycle as a normal level.
   On unload or retirement, refuse while players occupy the Age, move any
   remaining entities safely, flush pending chunk writes, detach the level,
   and synchronize removal. Retirement must not delete another Age's data.
5. Review the MIT-licensed Dynamic Dimensions code as an implementation
   reference. If any code is adapted, retain its copyright/license notice and
   identify the derived files. Prefer the smallest backend Rivencraft needs
   over a general-purpose library fork.

The release gate is a 26.3 integrated-client **and** dedicated-server matrix:
create two Ages with distinct seeds, explore chunks, travel while another
client remains online, reconnect, restart, revisit saved chunks, reseed for
future chunks, unload/reload, retire one Age without harming the other, and
verify normal travel without optional mods. Then repeat relevant paths with
available integrations. A failed synchronization must be reported and leave
the player in their current level, not crash or strand them.

## Implementation order

1. Keep `AgeDimensionService` independent of a concrete runtime-dimension
   implementation. The 1.21.1 Dynamic Dimensions calls now live in
   `AgeDimensionBackend`; the `AgeDimensionSeedMixin` is 1.21.1-only.
2. Create a separate 26.3/Java 25 build target. Replace the dimension backend,
   then migrate the main sources through the official NeoForge primers. Do not
   publish a partial JAR with missing Age generation.
3. Port optional integration classes one at a time. Keep unavailable mods
   optional and preserve their existing fallbacks. Upgrade JEI, TerraBlender,
   Serene Seasons/GlitchCore, Biomes O' Plenty, and Ruins only in the 26.3
   target; do not change the validated 1.21.1 dependency set.
4. Run compile, data/resource validation, new-world Age generation, Age
   save/restart/reload, direct and portal/book travel, client rendering, and
   dedicated-server tests on both targets. Test without optional mods, then
   with each available integration. Require an in-game check before release.

The core blocker is **not** a version number change: 26.3 makes a major API
jump and the required 1.21.1 runtime-dimension library has no 26.3 build.

## Build isolation started in #97

The repository root remains the playable 1.21.1/Java 21 build. A separate
`ports/mc263` Gradle build now resolves NeoForge 26.3.0.99 and compiles with
Java 25. The build workflow has separate Java 21 and Java 25 jobs. Its JAR
task remains disabled; this does not satisfy #97's final artifact criteria.

## First core slice in #98

The 26.3 target now has real Rivencraft metadata and an entrypoint. It
registers the Crystal Shard and Crystal Block with their reused 1.21.1
textures/models plus the 26.3 item-model definitions. `build` passed, and a
dedicated development server loaded the mod and reached `Done` with a new
world and no optional mods. The server was then stopped. This validates only
the entrypoint/registry/resource foundation. A development client also loaded
Rivencraft and reloaded its resources without reported missing models or
textures. The client logged the host's missing `libflite.so` narrator library;
this is unrelated to Rivencraft. Both test processes were stopped after
startup. This does **not** validate in-world client rendering or Age
functionality. Age generators, data, networking, and client code still
need migration; #98 remains open.

## Runtime-level prototype in #99

The 26.3 target has a first-party server-side runtime-level loader and a
SavedData seed index. It constructs each level with a `LevelStem` seed override,
publishes the level only after construction, and restores indexed Ages when
the Overworld loads. A dedicated-server probe created two separate Ages with
seeds `123456789` and `987654321`; after generating chunks, their terrain
fingerprints differed (`2865094` and `3227421`). Both levels, their region
files, seeds, and fingerprints survived a server restart, and the startup log
shows restoration before `Done`. The temporary operator-only
`rivencraft_port age` command exists solely to test this non-distributable
port workspace.

This is **not** issue #99 completion. The loader currently reuses the vanilla
Overworld generator because issue #98 has not ported authored generators or
Age definitions. The synchronized operator travel probe below does not port
normal book travel. The 26.3 JAR task remains disabled.

## Runtime client-catalog prototype in #100

The 26.3 target now sends the current dimension-key catalog to each joining
client and broadcasts a new catalog when a prototype Age is created or
retired. Clients update their known-level set and acknowledge a version; the
server's `rivencraft_port age enter <name>` probe refuses travel until that
acknowledgement arrives and the target is still loaded. A stale acknowledgement
does not satisfy the gate. This follows NeoForge's play-payload registration
and client-handler separation. It is not a general dynamic-registry sync for
authored dimension types, which have not been ported.

The dedicated-server probe used two simultaneous 26.3 clients. Both
acknowledged a newly created Age without reconnecting; a second client entered
an existing runtime Age; a player saved inside an Age reconnected after server
restart and remained there. The operator travel probe searches near origin for
safe footing and creates a small Crystal Block platform if none is found.
This probe is not the final book landing implementation.

`rivencraft_port age retire <name>` refuses to retire an Age containing a
player, then saves and closes it, removes it from the active index, and
broadcasts the reduced catalog. On the dedicated test server, the client
acknowledged creation and retirement even when they happened back-to-back; a
late acknowledgement for the intermediate catalog was ignored. Travel to the
retired Age was refused without moving the player, and retiring an occupied
Age was refused. The #101 lifecycle slice below now archives exact Age data.

This remains a **prototype**, not completion of #100: normal Linking and
Descriptive Book travel, authored dimension-type/generator registration, full
client registry synchronization, and an integrated-client regression pass
must follow the core port. The 26.3 JAR remains disabled. The local test
server was stopped after verification.

## Runtime lifecycle prototype in #101

The operator-only backend probe now supports `age unload`, `reload`, `reseed`,
and `retire` in addition to `create`, `list`, `sample`, and `enter`. Unload and
retirement refuse a level containing players. A full chunk/entity save and
close handles other entities; Minecraft's shutdown-style ticket deactivation
and startup-style activation preserve forced chunks across runtime reloads.
The loaded-dimension catalog is rebroadcast after unload/reload/reseed and
retirement, with stale acknowledgements ignored.

On the dedicated server, a generated Age unloaded and reloaded with the same
terrain fingerprint. Reseeding `lifetest` from `24680` to `13579` kept the
previously generated origin fingerprint `2898472`; previously ungenerated
chunks at offset 100 produced fingerprint `2897795`, identical to a fresh
`13579` control Age and different from a fresh `24680` control (`2863099`).
After restart, `lifetest` still reported seed `13579` and its original origin
fingerprint. Three consecutive unload/reload cycles with a connected client
completed; that client acknowledged the final catalog and intermediate stale
acknowledgements were ignored. Unloading the player's current Age was refused.

A force-loaded chunk and a summoned armor stand with UUID
`[I; -872307724, 883641011, -1239011659, 796091120]` survived repeated
runtime unload/reload and server restart. The entity could be queried again
after its chunk finished loading. The probe retired a different Age,
`seedcontrol`: only its directory moved to the sibling `world-retired-ages`
archive, other Age directories stayed in place, and reloading/recreating the
retired ID was refused after restart. A second archival probe exercised the
tombstone-before-move sequence and again moved only its own directory. The
tombstone is persisted before the archive move so an interrupted archival
cannot silently revive an old Age; an ordinary move failure attempts to
restore the index and level. Ten more consecutive unload/reload cycles
completed on the dedicated server, with its open file-descriptor count steady
at 218 before and after. That is a narrow smoke check, not proof of no leak.

This still does **not** close #101. The prototype has not been integrated with
normal books or the full 26.3 Age definition, nor has a long-running resource
leak test or interrupted-archive recovery drill been completed. Its dev world
and archive are under ignored `ports/mc263/build`, not a release save.

## Optional-integration probe in #102

On 2026-10-27, the published NeoForge 26.3 versions checked were JEI
31.17.0.95, TerraBlender 26.3.0.0.9, Biomes O' Plenty 26.3.0.0.15,
GlitchCore 26.3.0.0.5, and Serene Seasons 26.1.2.0.7 (its file is labelled
for Minecraft 26.3). Ruins advertises 26.3.1NF. Create/Ponder and
Immersive Portals still had no advertised compatible version. These are
availability checks, not API-compatibility claims.

The 26.3 development target now has the operator-only
`/rivencraft_port compat` command. It reports loaded optional mod IDs and
the count of registered biome keys by namespace, so integration smoke tests
can distinguish a missing addon from a missing biome registration. It does
not change Age generation. A clean dedicated server loaded with no optional
mods and reported 67 vanilla biomes. A separate dedicated-server launch with
TerraBlender, Biomes O' Plenty, GlitchCore, and Serene Seasons loaded all four;
the probe reported 68 `biomesoplenty` biome keys, and TerraBlender logged its
Overworld and Nether regions. Both launches stopped cleanly.

Issue #102 remains open. The 26.3 target still lacks authored Ages, JEI
guides, per-Age season policy, Ruins hooks, book previews and crystal portals,
so the relevant integration and fallback acceptance tests cannot yet pass.
The probe must not be mistaken for feature support. The existing 1.21.1
integration code and dependencies remain unchanged.

## First player-facing bridge in #104

The 26.3 port now registers a Descriptive Book with the Legacy item texture
and a persistent, network-synchronized Age-ID data component. The operator-only
`/rivencraft_port age book <name>` probe grants a book for an already indexed
Age; an unbound book does not create a world. Using the bound book calls the
same server-authoritative, catalog-acknowledged landing path as the existing
`age enter` probe. A missing or unloaded Age refuses travel. This avoids
trusting a book-supplied seed or creating a new Age from a forged item.

The dedicated-server smoke test still passed after this bridge, and a 26.3
development client loaded the new item model and texture without a missing
resource warning. The host still reports a missing Linux `libflite.so`
narrator library; this is not a Rivencraft item error. The client was stopped.
The player confirmed right-click travel in game. Book component persistence
across restart still needs a player test; the headless smoke test cannot
exercise it. To test the
bridge in a disposable 26.3 world as an operator:

1. `/rivencraft_port age create booktest 123456789`
2. Wait for the Age catalog acknowledgement, then
   `/rivencraft_port age book booktest`.
3. Right-click the granted book and verify arrival in
   `rivencraft:age/booktest`. Restart client and server, then use the same
   book again and verify it targets the same saved Age.

This is deliberately a **port probe**, not the final book workflow: the Book
Binder, naming UI, GUI preview, automatic return link, dropped-book entity, authored Age
plan, and Legacy landing rules are not yet connected. The bound book currently
remains in hand after travel. Do not distribute this target or mark #104 done.
For a local player test only, the normally disabled port JAR can be built with
`./gradlew -p ports/mc263 build -PallowIncompletePortJar=true`; its filename
retains `26.3-INCOMPLETE` and a `port-dev` version marker. This does not enable the normal
release artifact or imply that the full mod has been ported.

The first Prism test exposed a production-only catalog bug: Minecraft 26.3's
`ClientPacketListener.levels()` returned an immutable set, and the client
handler attempted to clear it. That threw `UnsupportedOperationException`
before the client could acknowledge the Age, so book travel was refused. The
handler now replaces the entire level set through a narrow access transformer
and acknowledges only after replacement. The corrected local test JAR is
`rivencraft-26.3-INCOMPLETE-0.0.0.1-port-dev.jar`. It built successfully;
the player used that JAR to verify actual travel in game on 2026-10-27.

### Linking Book return-path slice

The separate 26.3 target now registers a Linking Book using the Legacy bound
book sprite. `/rivencraft_port link book` grants an operator-only probe book
bound to the player's exact current dimension, coordinates, and facing. Its
destination is a persistent data component resolved by the server on use. A
missing dimension, unacknowledged catalog, same-dimension target without
Intra-Linking, out-of-bounds target, or obstructed arrival is rejected without
moving the player. This path does **not** generate a landing platform.

For a test, stand at an unobstructed spot in the Overworld and run
`/rivencraft_port link book`. Create and bind an Age Descriptive Book using the
steps above, travel into that Age, then right-click the Linking Book. It
should return to the exact bound spot and facing. Same-dimension use should
refuse. Repeat after a server restart to check component persistence. This
slice is `0.0.0.2-port-dev` and remains explicitly incomplete: normal
crafting/binding, modifiers, book GUI, origin-drop entity, and safe fallback
are still unported. The probe book remains in inventory after travel.

### Age-index durability after the first in-game return-link check

The first return-link test exposed a recoverable prototype failure: Seamless
Portals rejected a newly added runtime Age, the integrated server exited
abnormally, and a second Age created just before the exit was not present in
Rivencraft's saved index on restart. Its directory contained no saved chunks.
The `0.0.0.3-port-dev` slice flushes the index synchronously before announcing
newly created Ages to clients. It also flushes reseed changes. The dedicated
server smoke test now checks that both new Age IDs are already in the on-disk
index **before** it issues `stop`, then verifies both seeds/terrain after a
restart. This closes the ordinary interrupted-shutdown gap but is not a
substitute for a power-loss durability test or integration with other mods'
dynamic-dimension catalogs.

### Handheld Linking Book binding slice

The `0.0.0.4-port-dev` target adds a client-only book screen using the Legacy
book artwork. An unbound Linking Book accepts a player-chosen title; a
serverbound packet binds the held book to the player's *current* dimension,
coordinates and facing only after checking the book, title length and empty
target. A bound book opens the same screen and uses a server-validated
destination-panel click for travel. This replaces the earlier direct item-use
probe. The panel is a visible placeholder, **not** a live snapshot. The
rotating preview, completed book behavior (including origin drop), recipe,
modifiers, stand handling and other port systems remain unported.

To test this slice, use `/give @s rivencraft:linking_book` in a 26.3 test
world, stand at the intended return point, right-click the unbound book, enter
a name and bind. Travel to an Age, right-click the book again and click its
right-hand destination panel. Verify the named book persists across restart,
same-dimension travel is refused, and a replaced/removed held book cannot be
bound or used by a delayed screen packet. Do not treat this partial target as
a playable release.

The first `0.0.0.4-port-dev` in-game right-click exposed a 26.3 screen API
mistake: `Screen.extractRenderStateWithTooltipAndSubtitles` already calls
`extractBackground`, so the screen's second call raised `Can only blur once per
frame`. The `0.0.0.5-port-dev` fix removes that duplicate background call.
The next in-game check found that a bound Linking Book's right-hand panel did
not trigger travel: its target component was persistent but lacked a network
codec, so the client screen could not identify the book as bound. The
`0.0.0.6-port-dev` slice adds stream codecs for the Linking Book target and
Descriptive Book Age ID. Server-side held-item and destination checks remain
authoritative. This needs another in-game check before considering the slice
validated.
The `0.0.0.6-port-dev` retest showed the bound-book panel but left-clicking
did not even close the GUI. Minecraft 26.3's primary mouse button is
`InputConstants.MOUSE_BUTTON_LEFT` (value 1), while the port handler still
checked the 1.21.1 value 0. The `0.0.0.7-port-dev` slice uses the 26.3
constant. This still requires in-game verification of the full click/travel
path.
The player confirmed the `0.0.0.7-port-dev` bound Linking Book click/travel
path passes in game on 2026-10-27. The 26.3 target remains incomplete and is
not ready for a public release or closure of the parent port issue.

### Explicit technical alpha exception

At the player's request, `1.0.1.2-alpha.1` packages this limited 26.3 port as
an experimental alpha. It is **not** the full mod and does not pass the stable
release gate above. The alpha label and release notes must state that Ages use
prototype vanilla terrain, normal authoring and most content are absent, and
worlds should be disposable or backed up. The 1.21.1 stable release remains
independent; issues #96–#104 stay open until the full port and validation pass.

## Verification of this first slice

The 1.21.1 `compileJava` and `build` tasks passed offline after the backend
extraction. The GameTest server ran 93 tests; 92 passed, while
`twoblockdeskdropsonce` failed because breaking either desk half dropped zero
desks instead of one. That desk failure is outside the dimension-backend edit
and must be resolved or rechecked before a release. The 1.21.1 `build` task
passed again after the 26.3 registry slice.