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+## How to contribute
+- First, fork this repository into your Github account
+- Second, clone repository
+- Finaly, writing code push and PR to me
+
+## Writing code
+I checking the quality of code through Codacy when PR/Merge/Push. If you want to consider code quality in advance, please check the link below (not perfect, but very helpful).
+
+https://goreportcard.com/report/github.com/hahwul/dalfox
+
+e.g: `https://goreportcard.com/report/github.com/{your github account}/dalfox`
+
+## Build
+```
+go build
+```
+
+## Case study
+### How to add testing vector of XSS
+- Add new vector to https://github.com/hahwul/dalfox/blob/master/pkg/scanning/payload.go
+- Optimize but can affect performance, so please add a general and non-overlapping pattern.
+
+### How to add new entity(e.g event handler)
+- Add new pattern to https://github.com/hahwul/dalfox/blob/master/pkg/scanning/entity.go