explain in readme

README.md

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 >
 > af en sådan art eller beskaffenhed som lige er eller vil blive antydet, nævnt eller omtalt ofte om noget foragtet eller ubehageligt[^[1]](<https://ordnet.dk/ddo/ordbog?query=slige&tab=for>)
 
+A tool for developing high quality software.
+
+Project includes: the slige-programming language, a compiler for slige, a runtime environment, a graphical fontend for code analysis
+
+## Devtool
+
+### Source code viewer
+
+View program source code with syntax highlighting.
+
+![](docs/source_code_page.png)
+
+### Code coverage
+
+View what parts of the program are executed what amount of times.
+
+Includes 2 modes:
+- **Performance view**: Used to locate *hot* sections in the program. The more *hot*, ie. the more times a section is executed, the more critical the section is for overall performance.
+- **Test view**: Used to locate sections, that are not covered by tests. Automated tests are ineffective, if sections of the tested code, are not covered, ie. are never executed.
+
+![](docs/code_coverage_page_test_view.png)
+
+![](docs/code_coverage_tooltip_1.png)
+
+![](docs/code_coverage_tooltip_2.png)
+
+### Flame graph
+
+A flame graph displays what functions' individual execution time make up the overall execution time.
+
+![](docs/flame_graph_page.png)
+
+![](docs/flame_graph_tooltip.png)
+
+