Gryla McJar.py
A general-purpose utility for downloading and deobfuscating Minecraft JAR files. This tool handles fetching vanilla binaries, resolving mappings (Yarn, Mojang, Spigot, RetroMCP), and remapping JARs to named namespaces.
Features
- Vanilla Downloads: Fetch client or server JARs from Mojang's Piston meta or OmniArchive.
- Mapping Support:
- Yarn: Automatic lookup for Fabric's Yarn mappings (Modern and Legacy).
- Mojang: Official Mojang obfuscation maps.
- Spigot: BuildData-based remapping for server JARs.
- RetroMCP: Support for historical versions via MCPHackers.
- Smart Caching: Avoids redundant downloads and remapping operations by storing artifacts in
~/.cache/gryla(or OS equivalent).
Prerequisites
- Python 3.8+
- Java JRE/JDK: Required for the remapping tools (Tiny Remapper, SpecialSource-2, etc.).
- Git: Required for cloning Spigot BuildData.
Usage
1. Download a Vanilla JAR
Download a specific version without remapping. Use @omni@ prefix for OmniArchive versions.
mcjar get 1.20.1 client -o minecraft_1.20.1.jar
mcjar get @omni@b1.7.3 server
2. Remap a JAR
Download and remap a JAR to named mappings using a specified mapping provider.
Using Yarn (Default):
mcjar remap 1.20.1 client -m yarn
Using Mojang Mappings:
mcjar remap 1.19.2 server -m mojang -o server-mapped.jar
Using Spigot Mappings:
mcjar remap 1.12.2 server -m spigot
Using RetroMCP (for older versions):
mcjar remap b1.7.3 client -m retromcp
3. Cache Management
Clear the local cache directory to free up space or force fresh downloads.
mcjar clear_cache
Configuration
The storage directory can be overridden by setting the GRYLA_HOME environment variable. By default, it uses:
- Linux:
$XDG_CACHE_HOME/grylaor~/.cache/gryla - macOS:
~/Library/Caches/gryla - Windows:
%LOCALAPPDATA%\gryla\Cache
License
AGPL-V3
1 maintainer
Metadata
1 maintainer
Release files for mcjar 0.0.3
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | Provenance | |
|---|---|---|---|---|
| mcjar-0.0.3.tar.gz | 26.5 kB | With provenance | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| mcjar-0.0.3-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 55.7 kB
Release files / mcjar-0.0.3.tar.gz
| Download URL | mcjar-0.0.3.tar.gz |
|---|---|
| Size | 26.5 kB |
| Tags | Source |
|
SHA-256 checksum How to use checksums |
82364d33c7e139a84c7bab7952b230e63ba2abbbb5085e74f5ba71aa55126ca4
|
|
BLAKE2b-256 checksum How to use checksums |
a8d91f6e90cadbf18bb032b03f8e57cd8060da3781c937c615ce35f1a8c905db
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.7
|
Provenance
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Signed by GitHub Actions, verified by PyPI on Jan 10, 2026.
Transparency logRelease files / mcjar-0.0.3-py3-none-any.whl
| Download URL | mcjar-0.0.3-py3-none-any.whl |
|---|---|
| Size | 29.2 kB |
| Tags | Python 3 |
|
SHA-256 checksum How to use checksums |
7b7469ebe6af50e212ad6e9cc74cba1e008c74028aa43bcea864fbc754e62b99
|
|
BLAKE2b-256 checksum How to use checksums |
25dd04e19957e846e75e8d9bc45f11b362a21010c99014bd300040d0b49f1937
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.7
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jan 10, 2026.
Transparency logSecurity for mcjar 0.0.3
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
Full provenance
All 2 files in this release have been uploaded with provenance metadata.
Attestation for mcjar-0.0.3.tar.gz
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jan 10, 2026.
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