---
name: "umoci"
section: "1"
platform: "linux"
package: "umoci"
version: "0.6.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/umoci"
---

# umoci(1)

umoci modifies Open Container images

Aleksa Sarai SEPTEMBER 2018

## NAME

umoci - umoci modifies Open Container images

## SYNOPSIS

**umoci** \[**--help**\|**-h**\] \[**--version**\|**-v**\] \[**--log**={*debug*\|*info*\|*warn*\|*error*\|*fatal*}\] \[**--verbose**\] *command* \[*args*\]

## DESCRIPTION

**umoci** is a tool that allows for high-level modification of an OCI image layout and its tagged images. While **umoci** attempts to abstract the OCI image specification specifics, it is recommended that users of this tool read through the specification ⟨https://github.com/opencontainers/image-spec⟩ to make sure they understand the rough idea.

**umoci** is unique in that it is, at the time of writing, the first tool to allow for arbitrary modification of an OCI image in a high-level fashion (where all of the different blobs in an OCI image are all managed by **umoci** when doing a high-level operation such as [**umoci-repack**(1)](/umoci-repack/1.md)).

## GLOBAL OPTIONS

**--help, -h**\
   Print usage statement.

**--version, -v**\
   Print the version.

**--cpu-profile**=*filename*\
   Generate a CPU profile during umoci's execution and save it to *filename*.\
   This file is stored in Go's pprof ⟨https://golang.org/pkg/runtime/pprof/⟩ format and can be analysed using *go*\
   *tool pprof* or similar tools.

**--log**={*debug*\|*info*\|*warn*\|*error*\|*fatal*}\
   Set the logging level. The default is "warn".

**--verbose**\
   Alias for **--log=info**.

## COMMANDS

**init**\
   Create a new OCI layout. See [**umoci-init**(1)](/umoci-init/1.md) for more detailed usage\
   information.

**new**\
   Creates a blank tagged OCI image. See [**umoci-new**(1)](/umoci-new/1.md) for more detailed\
   usage information.

**unpack**\
   Unpacks a tagged image into an OCI runtime bundle. See [**umoci-unpack**(1)](/umoci-unpack/1.md)\
   for more detailed usage information.

**repack**\
   Repacks an OCI runtime bundle into a tagged image. See [**umoci-repack**(1)](/umoci-repack/1.md)\
   for more detailed usage information.

**config**\
   Modifies the image configuration of an OCI image. See [**umoci-config**(1)](/umoci-config/1.md) for\
   more detailed usage information.

**stat**\
   Displays status information of an image manifest. See [**umoci-stat**(1)](/umoci-stat/1.md) for\
   more detailed usage information.

**tag**\
   Creates a new tag in an OCI image. See [**umoci-tag**(1)](/umoci-tag/1.md) for more detailed\
   usage information.

**remove, rm**\
   Removes a tag from an OCI image. See [**umoci-remove**(1)](/umoci-remove/1.md) for more detailed\
   usage information.

**list, ls**\
   Lists the set of tags in an OCI image. See [**umoci-list**(1)](/umoci-list/1.md) for more\
   detailed usage information.

**gc**\
   Garbage collects all unreferenced OCI image blobs. See [**umoci-gc**(1)](/umoci-gc/1.md) for\
   more detailed usage information.

## SEE ALSO

[**umoci-init**(1)](/umoci-init/1.md), [**umoci-new**(1)](/umoci-new/1.md), [**umoci-unpack**(1)](/umoci-unpack/1.md), [**umoci-repack**(1)](/umoci-repack/1.md), [**umoci-config**(1)](/umoci-config/1.md), [**umoci-stat**(1)](/umoci-stat/1.md), [**umoci-tag**(1)](/umoci-tag/1.md), [**umoci-remove**(1)](/umoci-remove/1.md), [**umoci-list**(1)](/umoci-list/1.md), [**umoci-gc**(1)](/umoci-gc/1.md), [**skopeo**(1)](/skopeo/1.md)