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+# Nix
+
+## Chapter 1 
+* What is a `nix store`? 
+* What is a `derivation` and how does it look in the store?
+* What does the purely functionality of the nix mean?
+
+## Chapter 2. Install on Your Running System* What is a nix database?
+* What is a `nix profile`?
+* What is a `nix profile generation`? When new generations will be created?
+* What is a `nix expressions`?
+* What is `Nixpkgs`?
+* What is a `channel`?
+
+## Chapter 3. Enter the Environment
+* How to list installed derivations?
+* How to rollback installation of derivation?
+* What are the closures of derivation? 
+* How to make possible to run derivation from another machine using closures?
+* How to update the channel?
+
+## Chapter 4. The Basics of the Language
+* Does nix language include any statements?
+* What type system is used in nix?
+* What strategy of evaluation does nix use?
+* Provide examples using `nix-repl` for the next questions: 
+  * What are the rules with spaces near the slash `/` and minus `-` operators?
+  * How to specify the current directory?
+  * What quotes `strings` can be enclosed?
+  * What is a `string interpolation`? How it can be used?
+  * How to create a `list`? Are lists immutable?
+  * What syntax does `attribute set` have? How to select the attribute by key?
+  * What is a `recursive attribute set`? How to create it? When it can be useful?
+  * What is `if` expression syntax?
+  * What is `let` expression syntax? What is a scope of variable defined in `let`? How to define nested `let` expressions? How to define recursive `let`?
+  * How does `with` expression work?
+  
+## Chapter 5. Functions and Imports
+* Provide examples using `nix-repl` for the next questions: 
+  * What is a syntax of anonymous function with one parameter? How we can store it in variable? How to call a function?
+  * How to define a function with multiple parameters?
+  * What is a partial application? Is it allowed in nix language?
+  * Is pattern matching allowed for function args?
+  * How to specify default value of attribute?
+  * How to pass variadic attributes? How to access variadic attribute value? 
+  * How to import function from nix file?
+
+## Chapter 6. Our First Derivation
+* What builtin-function `derivation` does? What arguments does it receive?
+* How to distinguish the derivation from a simple set?
+* What fields are required in `.drv` file? What information should they contain?
+* How to inspect the derivation attributes?
+* What does `outPath` attribute show? How we can get the `outPath` of derivation?
+* When `.drv` file can be changed? What attribute does contain dependencies for derivation?
+* What does nix do in Instantiate/Evaluation time and in Realise/Build time?
+
+## Chapter 7. Working Derivation
+* Why no need to use shebang in the `.sh` script in nix?
+* What information does nix logs contain? What is a `/homeless-shelter` and why it can be pointed in logs? What is a path mentioned in `out`, is it global path? 
+* What args will `.drv` file have when we build bash script from file? What path to the script file will be used in `.drv` and why?
+* What `nix-build` command do? 
+* How to import the `nixpkgs` in `repl` and in `.nix` file code? 
+* What is the value does `nixpkgs` function return?
+* What does `inherit` keyword do? When it's convenient to use it?
+
+## Chapter 8. Generic Builders
+
+* Where to find and how to run the result builded wuth `nix-build`?
+* What is a `buildInputs` variable and what it does contain?
+* How to create more common builder? (describe the approach with a function)
+* How does `//` operator work?
+* Exercise:
+*  TODO: the exercise with common derivation function tool
+
+## Chapter 9. Automatic Runtime Dependencies
+
+* What is a NAR archive? How does it differ from TAR? How to archive nix store?
+* Should runtime dependencies be specified in the derivation?
+* What is `rpath` and should it be always in the runtime dependencies?
+* What tools can be used to remove unused runtime dependencies?
+
+## Chapter 10. Developing with nix-shell
+
+* What is the purpose of `nix-shell` tool?
+* What is the approach when we can call different phases manually? Describe the main principles.
+
+## Chapter 11. Garbage Collector
+
+* What is a GC root? Where are they stored?
+* What is a concept of garbage collection in nix?
+* What is the `indirect root` and how to garbage collect it?
+* Do old dependencies of referred to the build or profile remove automatically during garbage collection? How to remove them?
+
+## Chapter 12. Inputs Design Pattern
+
+* What is a concept of `single repository pattern`?
+* When can we use `default.nix` file?
+* What is a concept of `inputs pattern`?
+  TODO: add exercises for patterns