diff --git a/README.md b/README.md
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-# multini
-it's like crudini but for ini files with duplicate parameter names
+# Multini
+
+[![build](https://github.com/GenZmeY/multini/workflows/build/badge.svg)](https://github.com/GenZmeY/multini/actions)
+[![GitHub top language](https://img.shields.io/github/languages/top/GenZmeY/multini)](https://golang.org)
+[![GitHub](https://img.shields.io/github/license/genzmey/multini)](https://github.com/GenZmeY/multini/blob/master/LICENSE)
+[![GitHub release (latest by date)](https://img.shields.io/github/v/release/GenZmeY/multini)](https://github.com/GenZmeY/multini/releases)
+
+*Command line utility for manipulating ini files with duplicate key names.*
+
+A compiled version of multini is available on the [release page](https://github.com/GenZmeY/multini/releases).
+
+***
+
+# Description
+Some programs use ini file format with duplicate key names.  
+For example, these are games based on the [unreal engine](https://en.wikipedia.org/wiki/Unreal_Engine).  
+It might look like this (part of the Killing Floor 2 config):  
+```
+[OnlineSubsystemSteamworks.KFWorkshopSteamworks]
+ServerSubscribedWorkshopItems=2267561023
+ServerSubscribedWorkshopItems=2085786712
+ServerSubscribedWorkshopItems=2222630586
+ServerSubscribedWorkshopItems=2146677560
+```
+Most implementations only support having one property with a given name in a section. If there are several of them, only the first (or last) key will be processed, which is not enough in this case. multini solves this problem.
+
+**note:**  
+- multini is case sensitive;
+- quotes around the value are not processed (they are part of the value for multini);  
+- multi-line values are not supported.  
+(but this may change in the future)  
+
+# Build & Install (Manual)
+1. Install [golang](https://golang.org), [git](https://git-scm.com/), [make](https://www.gnu.org/software/make/);
+2. Clone this repo: `git clone https://github.com/GenZmeY/multini`
+3. Go to the source directory: `cd multini`
+4. Build: `make`
+5. Install: `make install`
+
+# Usage
+```
+Usage: multini [option]... ACTION ini_file [section] [param] [value]
+Actions:
+  -g, --get          Get values for a given combination of parameters.
+  -s, --set          Set values for a given combination of parameters.
+  -a, --add          Add values for a given combination of parameters.
+  -d, --del          Delete the given combination of parameters.
+  -c, --chk          Display parsing errors for the specified file.
+
+Options:
+  -e, --existing     For --set and --del, fail if item is missing.
+  -r, --reverse      For --add, adds an item to the top of the section
+  -i, --inplace      Lock and write files in place.
+                     This is not atomic but has less restrictions
+                     than the default replacement method.
+  -o, --output FILE  Write output to FILE instead. '-' means stdout
+  -u, --unix         Use LF as end of line
+  -w, --windows      Use CRLF as end of line
+  -q, --quiet        Suppress all normal output
+  -h, --help         Write this help to stdout
+      --version      Write version to stdout
+```
+
+# Examples
+**output a global value not in a section:**  
+`multini --get ini_file '' param`
+
+**output section:**  
+`multini --get ini_file section`
+
+**output list of existing sections:**  
+`multini --get ini_file`
+
+**output value:**  
+`multini --get ini_file section param`  
+- if there are several parameters, a list of all values of this parameter will be displayed
+
+**add/update a single parameter:**  
+`multini --set ini_file section parameter value`  
+- if there is no parameter, it will be added  
+- if the parameter exists, the value will be updated  
+- if the parameter exists and has several values, the parameter with the specified value will be set, the rest of the values will be deleted
+
+**add a parameter with specified value:**  
+`multini --add ini_file section parameter value`  
+- if there is no parameter, it will be added  
+- if the parameter exists and does not have the specified value, the new value will be added  
+- if the specified value repeats the existing one, no changes will be made
+
+**delete all parameters with specified name:**  
+`multini --del ini_file section parameter`
+
+**delete a parameter with specified name and value:**  
+`multini --del ini_file section parameter value`
+
+**delete a section:**  
+`multini --del ini_file section`
+
+**short options can be combined:**  
+`multini -gq ini_file section parameter value`  
+- check the existence of a parameter with a given value using the return code
+
+# License
+Copyright © 2020 GenZmeY
+
+The content of this repository is licensed under [MIT License](https://github.com/GenZmeY/multini/blob/master/LICENSE).
+