Minecraft Snapshot Reverse Engineering
This is where I post my findings from looking at the source code for every new Minecraft snapshot. I document the exact details of how each feature works, and everything not found in the official changelogs.
You can usually expect a post within a few days of the snapshot releasing.
Snapshot Posts
Subscribe via RSSMinecraft 25w43a
Some tweaks to the new features in the last snapshot, and a new environment attributes system.
Minecraft 25w42a
Some tweaks to the new features in the last snapshot, and a new environment attributes system.
Minecraft 25w41a
This massive snapshot adds the spear, nautilus, and zombie horse!
Minecraft 1.21.10
1.21.10 is now out.
Minecraft 1.21.10-rc1
A hotfix release candidate with changes to bubble column mechanics.
Minecraft 1.21.9
The Copper Age is out!
Minecraft 1.21.9-rc1
The first 1.21.9 release candidate is out.
Minecraft 1.21.9-pre4
Even more bugfixes.
Minecraft 1.21.9-pre3
Another copper golem performance fix.
Minecraft 1.21.9-pre2
The second 1.21.9 pre-release further tweaks the copper golem.
Minecraft 1.21.9-pre1
The first Copper Age pre-release is out with several fixes.
Minecraft 25w37a
This snapshot exposes many debug features that were previously developer-exclusive.
Minecraft 25w36b
This snapshot adds Player NPCs and bugfixes.
Minecraft 25w35a
Several Copper Golem fixes and a new protocol for managing servers.
Minecraft 25w34b
A smaller snapshot with tweaks to the Copper Golem and more.
Minecraft 25w33a
This snapshot adds the final 1.21.9 features.
Minecraft 25w32a
New copper decorations and bug fixes.
Minecraft 25w31a
The Copper Golem!
Minecraft 1.21.8
1.21.8 releases the critical fixes from the last release candidate.
Minecraft 1.21.8-rc1
A hotfix release candidate, fixing several graphics issues.
Minecraft 1.21.7
Minecraft 1.21.7 is out!
Minecraft 1.21.7-rc2
The second 1.21.7 release candidate is out with more bugfixes.
Minecraft 1.21.7-rc1
A surprise “hotfix” release candidate.
Minecraft 1.21.6
The Chase the Skies drop is out!
Minecraft 1.21.6-rc1
The first 1.21.6 release candidate is out.
Minecraft 1.21.6-pre4
Another bugfix pre-release.
Minecraft 1.21.6-pre3
This pre-release adds a new category for UI sounds.
Minecraft 1.21.6-pre2
Another pre-release with more bug fixes.
Minecraft 1.21.6-pre1
The first pre-release for 1.12.6 is out!
Minecraft 25w21a
New cloud patterns and other minor changes.
Minecraft 25w20a
This snapshot adds the final 1.21.6 features.
Minecraft 25w19a
A much smaller snapshot this time.
Minecraft 25w18a
Leads are now easier to craft.
Minecraft 25w17a
The Locator Bar is no longer experimental.
Minecraft 25w16a
This snapshot overhauls leash mechanics.
Minecraft 25w15a
The Happy Ghast is here.
Minecraft 1.21.5
The Spring to Life drop is out!
Minecraft 1.21.5-rc2
1.21.5 releases tomorrow.
Minecraft 1.21.5-rc1
The first release candidate for 1.21.5 is out, with no release date.
Minecraft 1.21.5-pre3
More bug fixes.
Minecraft 1.21.5-pre2
Fixes from the last pre-release.
Minecraft 1.21.5-pre1
As Minecraft Live approaches, the first pre-release for 1.21.5 is out.
Minecraft 25w10a
Another snapshot with more technical changes.
Minecraft 25w09b
Several crash fixes.
Minecraft 25w09a
A long-requested feature, fallen trees.
Minecraft 25w08a
New wolf sounds and spawn egg textures.
Minecraft 25w07a
This snapshot improves cartographer and wandering trader trades.
Minecraft 25w06a
Chicken.
Minecraft 25w05a
You would not believe your eyes.
Minecraft 25w04a
Movement fix reverts and more datapack changes.
Minecraft 25w03a
The GameTest system is now open to the public.
Minecraft 25w02a
The first snapshot of 2025, adding pig variants, new flowers, and many more tweaks.
Minecraft 1.21.4
The Gardens Awaken drop is out!
Minecraft 1.21.4-rc3
The third release candidate in two days.
Minecraft 1.21.4-rc2
The second 1.21.4 release candidate fixes one bug.
Minecraft 1.21.4-rc1
This Thanksgiving, we’re thankful for the first release candidate.
Minecraft 1.21.4-pre3
Another pre-release inches closer to 1.21.4.
Minecraft 1.21.4-pre2
A smaller pre-relase with some bug fixes.
Minecraft 1.21.4-pre1
The first 1.21.4 pre-release is out, starting to polish the winter drop features.
Minecraft 24w46a
A smaller snapshot with tweaks to Winter Drop content, components, and bugfixes.
Minecraft 24w45a
An overhaul to item models making many new features possible.
Minecraft 24w44a
This snapshot adds new features to the Pale Garden.
Minecraft 1.21.3
1.21.3 releases two critical fixes.
Minecraft 1.21.2
The “Bundles of Bravery” drop is out!
Minecraft 1.21.2-rc1
The first 1.21.2 release candidate is out.
Minecraft 1.21.2-pre5
Only two bugfixes this pre-release.
Minecraft 1.21.2-pre4
A few more bugfixes.
Minecraft 1.21.2-rc2
Another release candidate with some critical bugfixes.
Minecraft 1.21.2-pre3
Pre-releases are winding down to prepare for the update.
Minecraft 1.21.2-pre2
A much smaller snapshot with mostly bugfixes.
Minecraft 1.21.2-pre1
The Creaking Heart now supports comparators.
Minecraft 24w40a
This snapshot adds the Pale Garden and Creaking, coming this winter.
Minecraft 24w39a
Bundles are no longer experimental.
Minecraft 24w38a
A much smaller snapshot this time.
Minecraft 24w37a
Ender pearls now chunkload.
Minecraft 24w36a
A smaller snapshot this time, featuring custom equipment and bugfixes.
Minecraft 24w35a
This snapshot brings unexpected changes to raid spawning mechanics.
Minecraft 24w34a
More tweaks to experiments and performance improvements.
Minecraft 24w33a
As summer vacation ends, Mojang gives us one of the biggest snapshots ever.
Minecraft 1.21.1
1.21.1 releases the critical fixes from the last release candidate.
Minecraft 1.21.1-rc1
The first and probably only 1.21.1 release candidate is out.
Minecraft 1.21
1.21 is out!
Minecraft 1.21-rc1
The first 1.21 release candidate is out.
Minecraft 1.21-pre4
The smallest pre-release so far.
Minecraft 1.21-pre3
A few more bugfixes.
Minecraft 1.21-pre2
The second 1.21 pre-release is out with many bugfixes.
Minecraft 1.21-pre1
Leashable boats, portal-able entities, and many hidden changes.
Minecraft 24w21b
This snapshot adds data-driven jukeboxes and portal changes.
Minecraft 24w20a
Returning to Wednesday releases, this snapshot buffs witch farms and has an… interesting new piston sound.
Minecraft 24w19b
This snapshot improves chunk loading performance and fixes many, many bugs.
Minecraft 24w18a
The first snapshot of the full 1.21 release is out!
Minecraft 1.20.6
1.20.6 releases the critical fix from the last release candidate.
Minecraft 1.20.6-rc1
A release candidate for 1.20.6 is out, fixing a critical issue.
Minecraft 1.20.5
1.20.5 is out!
Minecraft 1.20.5-rc3
Just one bug fix.
Minecraft 1.20.5-rc2
Mojang, this is the fifth day in a row you’ve posted a snapshot.
Minecraft 1.20.5-rc1
The first 1.20.5 release candidate is out, expecting a release next week.
Minecraft 1.20.5-pre4
A very small pre-release this time.
Minecraft 1.20.5-pre3
Pre-releases two days in a row! Now with even more bugfixes.
Minecraft 1.20.5-pre2
Another pre-release with many bugfixes.
Minecraft 1.20.5-pre1
The first 1.20.5 pre-release is out, tweaking potion effects and Ominous Trials.
Minecraft 24w14a
Time to update those custom launchers.
Minecraft 24w14potato
For this year’s April Fools snapshot, Mojang adds everything.
Minecraft 24w13a
A massive snapshot adding the final 1.21 features.
Minecraft 24w12a
This snapshot makes it easier to find trial chambers and create cursed videos.
Minecraft 24w11a
A new snapshot adds a new way to deal absurd damage.
Minecraft 24w10a
This snapshot adds new wolf variants!
Minecraft 24w09a
This snapshot improves wolf armor and introduces data components.
Minecraft 24w07a
This snapshot adds a highly-requested skeleton variant and fixes hoppers.
Minecraft 24w06a
If fighting is sure to result in victory then you must fight!
Minecraft 24w05b
Goodbye strength 255.
Minecraft 24w05a
This snapshot unvaults the Vault.
Minecraft 24w04a
Another snapshot adding tweaks to the armadillo and technical changes.
Minecraft 24w03b
A surprisingly large b snapshot.
Minecraft 24w03a
This snapshot reduces the spawn chunks and adds the long-requested transfer packet!
Minecraft 23w51b
The armadillo was added.
Minecraft 1.20.4
1.20.4 releases the critical fix from the last release candidate.
Minecraft 1.20.4-rc1
A release candidate for 1.20.4 is out, fixing a critical issue.
Minecraft 1.20.3
1.20.3 is out!
Minecraft 1.20.3-rc1
The first 1.20.3 release candidate is out.
Minecraft 1.20.3-pre4
Only two more bugfixes.
Minecraft 1.20.3-pre3
As 1.20.3 approaches, this pre-release fixes more bugs.
Minecraft 1.20.3-pre2
Another pre-release changes how wind charges behave in water.
Minecraft 1.20.3-pre1
The first pre-release for 1.20.3 is out, adding tools for server resource packs and bugfixes.
Minecraft 23w46a
The crafter and copper bulb were nerfed.
Minecraft 23w45a
This massive snapshot adds Trial Chambers and the Breeze.
Minecraft 23w44a
A smaller snapshot with some small improvements.
Minecraft 23w43b
Fixes a few crashes from 23w43a.
Minecraft 23w43a
A new 1.21 snapshot adds tick warping!
Minecraft 23w42a
It’s here.
Minecraft 23w41a
Decorated pots can now store items!
Minecraft 23w40a
The first snapshot for 1.20.3 is out!
Minecraft 1.20.2
1.20.2 is out!
Minecraft 1.20.2-rc2
A small release candidate fixes villagers suffocating in minecarts.
Minecraft 1.20.2-rc1
The first 1.20.2 release candidate is out, full release planned next week.
Minecraft 1.20.2-pre4
Another snapshot with even more bugfixes.
Minecraft 1.20.2-pre3
A few more bugfixes before the 1.20.2 release.
Minecraft 1.20.2-pre2
A new 1.20.2 pre-release fixes bugs and reverts the recipe book changes.
Minecraft 1.20.2-pre1
The first 1.20.2 pre-release reworks armorer and cartographer villagers.
Minecraft 23w35a
Another snapshot with bug fixes.
Minecraft 23w33a
This snapshot adds skin/name reporting and mob attack reach changes.
Minecraft 23w32a
This snapshot brings vibration changes and many technical changes.
Minecraft 23w31a
The first snapshot for 1.20.2 is out!
Minecraft 1.20.1
1.20.1 is out!
Minecraft 1.20.1-rc1
A 1.20.1 release candidate has been released, fixing some critical issues.
Minecraft 1.20
1.20 is out!
Minecraft 1.20-rc1
The first 1.20 release candidate wraps up development.
Minecraft 1.20-pre7
This pre-release adds symbolic link validation.
Minecraft 1.20-pre6
Yet another pre-release with some technical tweaks.
Minecraft 1.20-pre5
A new pre-release inches closer to 1.20 with more bug fixes.
Minecraft 1.20-pre4
A crash fix from the previous pre-release.
Minecraft 1.20-pre3
Pre-release 3 fixes even more bugs.
Minecraft 1.20-pre2
Another pre-release, another ancient bug fixed.
Minecraft 1.20-pre1
The first 1.20 pre-release is out, adding universal dyeing and fixing an ancient bug.
Minecraft 23w18a
A new snapshot adds telemetry tweaks and fixes an 11 year old bug.
Minecraft 23w17a
New music, new advancements, and a new light engine!
Minecraft 23w16a
This snapshot tweaks trail ruins and fixes the infamous chunk border lag spike.
Minecraft 23w14a
Another snapshot is out with highly-requested bugfixes.
Minecraft 23w13a or b
23w13a is out. Or is it 23w13b? Vote now!
Minecraft 23w13a
A new 1.20 snapshot fixes bugs in the previous snapshot.
Minecraft 23w12a
The first 1.20 update is out and definitely does not have “no more major features”.
Minecraft 1.19.4
1.19.4 is out!
Minecraft 1.19.4-rc3
Another release candidate prepares for a release tomorrow.
Minecraft 1.19.4-rc2
Another release candidate fixes Guardian thorns.
Minecraft 1.19.4-rc1
The first 1.19.4 release candidate is out.
Minecraft 1.19.4-pre4
1.19.4 gets closer with even more bug fixes.
Minecraft 1.19.4-pre3
This 1.19.4 pre-release contains a few more texture tweaks and bug fixes.
Minecraft 1.19.4-pre2
Another 1.19.4 pre-release contains bug fixes and texture tweaks.
Minecraft 1.19.4-pre1
The first 1.19.4 pre-release is here with lots of bug fixes.
Minecraft 23w07a
This massive snapshot adds cherry trees, archaeology, and the Sniffer!
Minecraft 23w06a
A new 1.19.4 snapshot adds efficient ways to display text, blocks, and items!
Minecraft 23w05a
A new 1.19.4 snapshot adds armor trims to leather armor.
Minecraft 23w04a
Another 1.19.4 snapshot is out, bringing an overhaul to smithing and armor trims!
Minecraft 23w03a
The first snapshot for 1.19.4 is out!
Minecraft 1.19.3
1.19.3 is out!
Minecraft 1.19.3-rc3
1.19.3 has been delayed by one day.
Minecraft 1.19.3-rc2
The second and probably final 1.19.3 release candidate is out.
Minecraft 1.19.3-rc1
The first 1.19.3 release candidate is out.
Minecraft 1.19.3-pre3
Another pre-release is out with some bugfixes.
Minecraft 1.19.3-pre2
Another pre-release is out with some bugfixes.
Minecraft 1.19.3-pre1
The first 1.19.3 pre-release is here with custom player head sounds.
Minecraft 22w46a
A new snapshot is out, adding playable mob sounds.
Minecraft 22w45a
A new snapshot with even more creative inventory tweaks.
Minecraft 22w44a
Another snapshot focusing on quality-of-life changes.
Minecraft 22w43a
Another 1.19.3 snapshot is here, fixing bugs from 22w42a.
Minecraft 22w42a
The first 1.19.3 (and 1.20) snapshot is here!
Minecraft 1.19.1-pre3
A new pre-release is out with some minor fixes.
Minecraft 1.19.1-pre2
Mojang has delayed 1.19.1 and released a second pre-release.
Minecraft 1.19.1-rc1
The first 1.19.1 release candidate is here, adding more context to reports.
Minecraft 1.19.1-pre1
The first 1.19.1 pre-release is here, adding permanent multiplayer bans.
Minecraft 22w24a
The first 1.19.1 snapshot is here, adding player chat reporting.
Minecraft 1.19
The Wild Update is here!
Minecraft 1.19-rc2
The second release candidate is out with very few changes.
Minecraft 1.19-rc1
The first release candidate is out.
Minecraft 1.19-pre5
Another pre-release with some game event changes.
Minecraft 1.19-pre4
A small pre-release with a few bug fixes.
Minecraft 1.19-pre3
The Warden just got its final buff.
Minecraft 1.19-pre2
Another 1.19 pre-release is out.
Minecraft 1.19-pre1
The first 1.19 pre-release is out!
Minecraft 22w19a
A new snapshot with lots of technical changes.
Minecraft 22w18a
Another smaller snapshot with some allay and warden tweaks.
Minecraft 22w17a
A smaller snapshot this time, adding goat horns.
Minecraft 22w16b
Another snapshot is out, adding a new music disc and some random changes.
Minecraft 22w15a
This snapshot gives the warden a massive buff.
Minecraft 22w14a
This snapshot brings the new mangrove swamp biome.
Minecraft 22w13oneblockatatime
This snapshot may be a joke, but the automation and speedrunning potential is not!
Minecraft 22w13a
The allay is here!
Minecraft 22w12a
The second 1.19 snapshot is out, adding the Warden.
Minecraft 22w11a
The first 1.19 snapshot is out, and update suppression is now patched.
Minecraft 1.18.2
1.18.2 is now out.
Minecraft 1.18.2-rc1
The first 1.18.2 release candidate is out.
Minecraft 1.18.2-pre3
The third 1.18.2 pre-release brings more bug and crash fixes.
Minecraft 1.18.2-pre2
The second 1.18.2 pre-release is out.
Minecraft 1.18.2-pre1
Three snapshots in a row!? 1.18.2 is coming up soon.
Minecraft 1.19 Experimental Snapshot 1
Here we go… the first snapshot for 1.19 is out!
Minecraft 22w07a
Another snapshot for 1.18.2 adds biome customization and some sneaky mob spawning changes.
Minecraft 22w06a
Another snapshot for 1.18.2 is out with many hidden changes.
Minecraft 22w05a
Another snapshot for 1.18.2 is out.
Minecraft 22w03a
The first snapshot of 2022 is here.
Minecraft 1.18.1
1.18.1 is now out.
Minecraft 1.18.1-rc3
1.18.3-rc3 fixes a critical security issue.
Minecraft 1.18
The Caves and Cliffs Update Part 2 is finally out!
Minecraft 1.18.1-pre2
This second 1.18 pre-release is out, now with Java 17!
Minecraft 21w44a
21w44a is out now, adding optimizations and the ability to opt-out of player listings.
Minecraft 21w43a
21w43a is out and adds blending of old worlds.
Minecraft 21w42a
Another 1.18 snapshot is out, featuring a new music disc!
Minecraft 21w41a
This snapshot officially changes the random number generator used for worldgen.
Minecraft 21w40a
A new snapshot is out, buffing copper ore.
Minecraft 21w39a
The third 1.18 snapshot is out, and old worlds can finally be opened again.
Minecraft 21w37a
The first non-experimental 1.18 snapshot is out!
Minecraft 1.18 Experimental Snapshot 3
The third experimental snapshot for 1.18 is out, with some major mob spawning changes!
Minecraft 1.18 Experimental Snapshot 1
The first snapshot for 1.18 is out! It is an experimental snapshot, you must download it from the changelog.
Minecraft 1.17.1
Minecraft 1.17.1 is out! There are no new changes since 1.17.1-rc2.
Minecraft 1.17.1-rc2
The second release candidate fixes some critical issues.
Minecraft 1.17.1-rc1
The first release candidate for 1.17.1 is out, there are no new mechanics to investigate.
Minecraft 1.17.1-pre3
This pre-release buffs adds a couple bugfixes, there are no new mechanics to investigate.
Minecraft 1.17.1-pre2
This pre-release buffs diamond ore, nerfs emerald ore, and introduces a couple stealth fixes.
Minecraft 1.17.1-pre1
The first 1.17.1 pre-release changes axolotl and goat breeding mechanics, and a buff to drowned copper farms and powder snow farms!
Minecraft 1.17
The Caves and Cliffs Update Part 1 is finally out!
Minecraft 1.17-rc2
The second (and probably final) pre-release is out. The changelog says, “fixed a few critical issues”, but now we know what those critical issues are.
Minecraft 1.17-rc1
The first release candidate is out! As expected, it has no new features to investigate.
Minecraft 1.17-pre5
The pre-releases are wrapping up, this one has no new features to investigate.
Minecraft 1.17-pre4
The fourth pre-release fixes a few more bugs.
Minecraft 1.17-pre3
The third pre-release changes glow squid spawning conditions and fixes more bugs.
Minecraft 1.17-pre2
The second pre-release is out and so is the release date!
Minecraft 1.17-pre1
The first 1.17 pre-release is out!
Minecraft 21w20a
This snapshot adds a new way to farm hanging roots, new narrator features, and plenty of bugfixes.
Minecraft 21w19a
This snapshot makes candles, bundles, and sculk sensors command-only, and upgrades Java to Java 16.
Minecraft 21w18a
Another smaller snapshot that makes screaming goats use their ram attack more often.
Minecraft 21w17a
A smaller snapshot with a copper ore buff and even more tweaks to the raw ore block textures.
Minecraft 21w16a
This snapshot adds dripstone and azalea growth, as well as even more raw ore texture tweaks.
Minecraft 21w15a
This snapshot adds goat ramming, raw ore blocks, and marker entities. The Caves & Cliffs update was also split in two.
Minecraft 21w14a
Now you can use fortune on iron, gold, and copper ore! A simple snapshot, but a massive game changer.
Minecraft 21w13a
This snapshot adds goats, a darker splash screen, axolotl spawns, and the light block!