The idea of interactive programming is at the very heart of CIDER.

Programmers are expected to program in a very dynamic and incremental manner, constantly re-evaluating existing Clojure definitions and adding new ones to their running applications. You never stop/start a Clojure application while using CIDER - you're constantly interacting with it and changing it.

CIDER comes with a handy minor mode called cider-mode (complementing clojure-mode) that allows you to evaluate code in your Clojure source files and load it directly in the REPL. cider-mode is the primary way you're supposed to be interacting with your REPL process. If you want to get productive with CIDER, you'll have to get intimately familiar with it.

Using cider-mode

Here's a list of cider-mode's keybindings:

Command	Keyboard shortcut	Description
cider-eval-last-sexp	C-x C-e C-c C-e	Evaluate the form preceding point and display the result in the echo area and/or in an buffer overlay (according to cider-use-overlays). If invoked with a prefix argument, insert the result into the current buffer.
cider-eval-last-sexp-and-replace	C-c C-v w	Evaluate the form preceding point and replace it with its result.
cider-eval-last-sexp-to-repl	C-c M-e	Evaluate the form preceding point and output it result to the REPL buffer. If invoked with a prefix argument, takes you to the REPL buffer after being invoked.
cider-insert-last-sexp-in-repl	C-c M-p	Load the form preceding point in the REPL buffer.
cider-pprint-eval-last-sexp	C-c C-p	Evaluate the form preceding point and pretty-print the result in a popup buffer.
cider-pprint-eval-defun-at-point	C-c C-f	Evaluate the top level form under point and pretty-print the result in a popup buffer.
cider-eval-defun-at-point	C-M-x C-c C-c	Evaluate the top level form under point and display the result in the echo area.
cider-eval-sexp-at-point	C-c C-v v	Evaluate the form around point.
cider-eval-defun-at-point	C-u C-M-x C-u C-c C-c	Debug the top level form under point and walk through its evaluation
cider-eval-region	C-c C-v r	Evaluate the region and display the result in the echo area.
cider-interrupt	C-c C-b	Interrupt any pending evaluations.
cider-macroexpand-1	C-c C-m	Invoke macroexpand-1 on the form at point and display the result in a macroexpansion buffer. If invoked with a prefix argument, macroexpand is used instead of macroexpand-1.
cider-macroexpand-all	C-c M-m	Invoke clojure.walk/macroexpand-all on the form at point and display the result in a macroexpansion buffer.
cider-eval-ns-form	C-c C-v n	Eval the ns form.
cider-repl-set-ns	C-c M-n	Switch the namespace of the REPL buffer to the namespace of the current buffer.
cider-switch-to-repl-buffer	C-c C-z	Switch to the relevant REPL buffer. Use a prefix argument to change the namespace of the REPL buffer to match the currently visited source file.
cider-switch-to-repl-buffer	C-u C-u C-c C-z	Switch to the REPL buffer based on a user prompt for a directory.
cider-load-buffer-and-switch-to-repl-buffer	C-c M-z	Load (eval) the current buffer and switch to the relevant REPL buffer. Use a prefix argument to change the namespace of the REPL buffer to match the currently visited source file.
cider-display-connection-info	C-c M-d	Display default REPL connection details, including project directory name, buffer namespace, host and port.
cider-rotate-default-connection	C-c M-r	Rotate and display the default nREPL connection.
cider-find-and-clear-repl-output	C-c C-o	Clear the last output in the REPL buffer. With a prefix argument it will clear the entire REPL buffer, leaving only a prompt. Useful if you're running the REPL buffer in a side by side buffer.
cider-load-buffer	C-c C-k	Load (eval) the current buffer.
cider-load-file	C-c C-l	Load (eval) a Clojure file.
cider-refresh	C-c C-x	Reload all modified files on the classpath. If invoked with a prefix argument, reload all files on the classpath. If invoked with a double prefix argument, clear the state of the namespace tracker before reloading.
cider-doc	C-c C-d d C-c C-d C-d	Display doc string for the symbol at point. If invoked with a prefix argument, or no symbol is found at point, prompt for a symbol.
cider-javadoc	C-c C-d j C-c C-d C-j	Display JavaDoc (in your default browser) for the symbol at point. If invoked with a prefix argument, or no symbol is found at point, prompt for a symbol.
cider-grimoire	C-c C-d r C-c C-d C-r	Lookup symbol in Grimoire.
cider-grimoire-web	C-c C-d w C-c C-d C-w	Open the grimoire documentation for symbol in a web browser.
cider-apropos	C-c C-d a C-c C-d C-a	Apropos search for functions/vars.
cider-apropos-documentation	C-c C-d f C-c C-d C-f	Apropos search for documentation.
cider-apropos-documentation-select	C-c C-d e C-c C-d C-e	Apropos search for documentation & select.
cider-inspect	C-c M-i	Inspect expression. Will act on expression at point if present.
cider-toggle-trace-var	C-c M-t v	Toggle var tracing.
cider-toggle-trace-ns	C-c M-t n	Toggle namespace tracing.
cider-undef	C-c C-u	Undefine a symbol. If invoked with a prefix argument, or no symbol is found at point, prompt for a symbol.
cider-test-run-test	C-c C-t t C-c C-t C-t	Run test at point.
cider-test-rerun-test	C-c C-t g C-c C-t C-g	Re-run the last test you ran.
cider-test-run-ns-tests	C-c C-t n C-c C-t C-n	Run tests for current namespace.
cider-test-run-loaded-tests	C-c C-t l C-c C-t C-l	Run tests for all loaded namespaces.
cider-test-run-project-tests	C-c C-t p C-c C-t C-p	Run tests for all project namespaces. This loads the additional namespaces.
cider-test-rerun-failed-tests	C-c C-t r C-c C-t C-r	Re-run test failures/errors.
cider-test-show-report	C-c C-t b C-c C-t C-b	Show the test report buffer.
cider-find-var	M-.	Jump to the definition of a symbol. If invoked with a prefix argument, or no symbol is found at point, prompt for a symbol.
cider-find-resource	C-c M-.	Jump to the resource referenced by the string at point.
cider-find-ns	C-c C-.	Jump to some namespace on the classpath.
cider-pop-back	M-,	Return to your pre-jump location.
complete-symbol	M-TAB	Complete the symbol at point.
cider-quit	C-c C-q	Quit the current nREPL connection. With a prefix argument it will quit all connections.

There's no need to memorize this list. In any Clojure buffer with cider-mode active you'll have a CIDER menu available, which lists all the most important commands and their keybindings. You can also invoke C-h f RET cider-mode to get a list of the keybindings for cider-mode.

An even better solution would be to install which-key, which will automatically show you a list of available keybindings as you start typing some keys. This will simplify your interactions with CIDER quite a lot (especially in the beginning). Here's what you'd see if you typed C-c C-d in a Clojure buffer: