diff --git a/.cirrus.yml b/.cirrus.yml
index b05e32b..1624566 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -12,7 +12,7 @@ main_freebsd_task:
     - pip install --user Jinja2 PyYAML
   main_build_script:
     - ./autogen.sh
-    - ./configure --enable-debug --enable-checks-all CFLAGS='-O3'
+    - ./configure --enable-assert --enable-checks-all CFLAGS='-O3'
     - make
     - sudo make install
   main_test_script:
@@ -32,7 +32,7 @@ mruby_freebsd_task:
     - unzip mruby-3.1.0.zip
   main_build_script:
     - ./autogen.sh
-    - ./configure --enable-debug CFLAGS='-O3'
+    - ./configure --enable-assert CFLAGS='-O3'
     - make
     - sudo make install
   mruby_test_script:
@@ -56,7 +56,7 @@ ruby_freebsd_task:
     - sudo make install
   main_build_script:
     - ./autogen.sh
-    - ./configure --enable-debug CFLAGS='-O3'
+    - ./configure --enable-assert CFLAGS='-O3'
     - make
     - sudo make install
   ruby_build_script:
@@ -78,7 +78,7 @@ rust_freebsd_task:
     - curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
   main_build_script:
     - ./autogen.sh
-    - ./configure --enable-debug CFLAGS='-O3'
+    - ./configure --enable-assert CFLAGS='-O3'
     - make
     - sudo make install
   rust_test_script:
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 2962234..7b64438 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -24,7 +24,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        debug: ['--disable-debug', '--enable-debug']
+        assert: ['--disable-assert', '--enable-assert']
         cc: ['gcc', 'clang', 'tcc']
         opt: ['', '-O0', '-O3']
     steps:
@@ -34,7 +34,7 @@ jobs:
       - name: autogen
         run: ./autogen.sh
       - name: configure
-        run: ./configure ${{matrix.debug}} --enable-checks --enable-checks-pthreads --enable-checks-python CC='${{matrix.cc}}' CFLAGS='${{matrix.opt}}'
+        run: ./configure ${{matrix.assert}} --enable-checks --enable-checks-pthreads --enable-checks-python CC='${{matrix.cc}}' CFLAGS='${{matrix.opt}}'
       - name: make
         run: make
       - name: check
@@ -99,7 +99,7 @@ jobs:
       - name: autogen
         run: ./autogen.sh
       - name: configure
-        run: ./configure --enable-debug --enable-checks --enable-checks-pthreads --enable-checks-python --without-${{matrix.packages.without}} ${{matrix.packages.dependencies}}
+        run: ./configure --enable-assert --enable-checks --enable-checks-pthreads --enable-checks-python --without-${{matrix.packages.without}} ${{matrix.packages.dependencies}}
       - name: make
         run: make
       - name: check
@@ -111,7 +111,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        debug: ['--disable-debug', '--enable-debug']
+        assert: ['--disable-assert', '--enable-assert']
     steps:
       - uses: actions/checkout@v2
       - name: apt update
@@ -121,7 +121,7 @@ jobs:
       - name: autogen
         run: ./autogen.sh
       - name: configure
-        run: ./configure --host='i386-elf' ${{matrix.debug}} --enable-freestanding --with-libc CC="$(which i686-linux-gnu-gcc)"
+        run: ./configure --host='i386-elf' ${{matrix.assert}} --enable-freestanding --with-libc CC="$(which i686-linux-gnu-gcc)"
       - name: make
         run: make
 
@@ -138,7 +138,7 @@ jobs:
       - name: extract
         run: tar -xzf "libkernaux-$(cat VERSION).tar.gz"
       - name: configure
-        run: cd "libkernaux-$(cat VERSION)" && ./configure --enable-debug --enable-checks --enable-checks-pthreads --enable-checks-python
+        run: cd "libkernaux-$(cat VERSION)" && ./configure --enable-assert --enable-checks --enable-checks-pthreads --enable-checks-python
       - name: make
         run: cd "libkernaux-$(cat VERSION)" && make
       - name: check
diff --git a/.github/workflows/mruby.yml b/.github/workflows/mruby.yml
index 64c44cc..e654d1c 100644
--- a/.github/workflows/mruby.yml
+++ b/.github/workflows/mruby.yml
@@ -13,7 +13,7 @@ jobs:
       MRUBY_YAML_USE_SYSTEM_LIBRARY: x
     strategy:
       matrix:
-        debug: ['--disable-debug', '--enable-debug']
+        assert: ['--disable-assert', '--enable-assert']
         packages:
           - configure: ''
           - configure: '--without-all'
@@ -30,7 +30,7 @@ jobs:
       - name: autogen
         run: ./autogen.sh
       - name: configure
-        run: ./configure ${{matrix.debug}} ${{matrix.packages.configure}} CFLAGS='-O3'
+        run: ./configure ${{matrix.assert}} ${{matrix.packages.configure}} CFLAGS='-O3'
       - name: make
         run: make
       - name: install
diff --git a/.github/workflows/ruby.yml b/.github/workflows/ruby.yml
index 5f7ab12..109932d 100644
--- a/.github/workflows/ruby.yml
+++ b/.github/workflows/ruby.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        debug: ['--disable-debug', '--enable-debug']
+        assert: ['--disable-assert', '--enable-assert']
         packages:
           - configure: ''
           - configure: '--without-all'
@@ -28,7 +28,7 @@ jobs:
       - name: autogen
         run: ./autogen.sh
       - name: configure
-        run: ./configure ${{matrix.debug}} ${{matrix.packages.configure}} CFLAGS='-O3'
+        run: ./configure ${{matrix.assert}} ${{matrix.packages.configure}} CFLAGS='-O3'
       - name: make
         run: make
       - name: install
diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index 3fb6f01..d47c2de 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        debug: ['--disable-debug', '--enable-debug']
+        assert: ['--disable-assert', '--enable-assert']
         packages:
           - configure: ''
           - configure: '--without-all'
@@ -27,7 +27,7 @@ jobs:
       - name: autogen
         run: ./autogen.sh
       - name: configure
-        run: ./configure ${{matrix.debug}} ${{matrix.packages.configure}} CFLAGS='-O3'
+        run: ./configure ${{matrix.assert}} ${{matrix.packages.configure}} CFLAGS='-O3'
       - name: make
         run: make
       - name: install
diff --git a/.openbsd.yml b/.openbsd.yml
index cfd6ca3..c7a3abd 100644
--- a/.openbsd.yml
+++ b/.openbsd.yml
@@ -31,7 +31,7 @@ tasks:
   - build: |
       cd libkernaux
       ./autogen.sh
-      ./configure --enable-debug --enable-checks-all CFLAGS='-O3'
+      ./configure --enable-assert --enable-checks-all CFLAGS='-O3'
       make
       doas make install
   - test: |
diff --git a/ChangeLog b/ChangeLog
index e3d9e3d..5b6bdbf 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,10 @@
 2022-12-13  Alex Kotov  <kotovalexarian@gmail.com>
 
 	* tests/Makefile.am: Fix FreeBSD builds
+	* configure.ac: Rename feature "--(enable|disable)-debug" to
+	"--(enable|disable)-assert"
+	* include/kernaux/assert.h: Rename definition "KERNAUX_DEBUG" to
+	"KERNAUX_ENABLE_ASSERT"
 
 2022-12-12  Alex Kotov  <kotovalexarian@gmail.com>
 
diff --git a/README.md b/README.md
index 4c52377..de560c1 100644
--- a/README.md
+++ b/README.md
@@ -100,10 +100,10 @@ zero). Work-in-progress APIs can change at any time.
 `#define` the following C preprocessor macros before including `<kernaux.h>` and
 `<kernaux/*.h>` files. They have effect on your code, not the library code.
 
-* `KERNAUX_DEBUG` - enable assertions.
 * `KERNAUX_ACCESS_PRIVATE` - disable access modifier "private". Don't do this!
 * `KERNAUX_ACCESS_PROTECTED` - disable access modifier "protected". Only do this
   in a file where you implement an inherited type.
+* `KERNAUX_ENABLE_ASSERT` - enable assertions.
 * `KERNAUX_BITFIELDS` - enable bitfields in packed structs. It doesn't follow
   the C standard and may be incompatible with some compilers.
 
@@ -115,7 +115,7 @@ void (*kernaux_assert_cb)(const char *file, int line, const char *msg)
 ```
 
 Assertion callback. It's better to always set it to some function which always
-interrupts the execution, even when debugging is disabled. It may for example
+interrupts the execution, even when assertions are disabled. It may for example
 call `abort()` in hosted environment, raise an exception in Ruby, panic in Rust
 or power off the machine in freestanding environment. It may also log the error
 location and message.
@@ -152,7 +152,7 @@ stable options.
 
 #### Features
 
-* `--(enable|disable)-debug` - debugging
+* `--(enable|disable)-assert` - assertions
 * `--(enable|disable)-float` - floating-point arithmetic
 * `--(enable|disable)-werror` - fail on warning (`CFLAGS+='-Werror'`)
 
diff --git a/configure.ac b/configure.ac
index ff4a35c..bb1d583 100644
--- a/configure.ac
+++ b/configure.ac
@@ -42,7 +42,7 @@ AM_INIT_AUTOMAKE([1.16 subdir-objects])
 ###############
 
 dnl Features (enabled by default)
-AC_ARG_ENABLE([debug],           AS_HELP_STRING([--disable-debug],          [disable debugging]))
+AC_ARG_ENABLE([assert],          AS_HELP_STRING([--disable-assert],         [disable assertions]))
 AC_ARG_ENABLE([float],           AS_HELP_STRING([--disable-float],          [disable floating-point arithmetic]))
 AC_ARG_ENABLE([werror],          AS_HELP_STRING([--disable-werror],         [disable -Werror]))
  
@@ -127,7 +127,7 @@ AS_IF([test "$with_all" = no], do_without_all)
 ##################
 
 dnl Features (enabled by default)
-AS_IF([test "$enable_debug"           = no ], [enable_debug=no],            [enable_debug=yes])
+AS_IF([test "$enable_assert"          = no ], [enable_assert=no],           [enable_assert=yes])
 AS_IF([test "$enable_float"           = no ], [enable_float=no],            [enable_float=yes])
 AS_IF([test "$enable_werror"          = no ], [enable_werror=no],           [enable_werror=yes])
 
@@ -190,7 +190,7 @@ dnl Architecture (additional)
 AM_CONDITIONAL([ASM_X86],                [test "$host_cpu" = i386 -o "$host_cpu" = x86_64])
 
 dnl Features (enabled by default)
-AM_CONDITIONAL([ENABLE_DEBUG],           [test "$enable_debug"           = yes])
+AM_CONDITIONAL([ENABLE_ASSERT],          [test "$enable_assert"          = yes])
 AM_CONDITIONAL([ENABLE_FLOAT],           [test "$enable_float"           = yes])
 AM_CONDITIONAL([ENABLE_WERROR],          [test "$enable_werror"          = yes])
 
@@ -241,7 +241,7 @@ AS_IF([test "$host_cpu" = i386],              [AC_DEFINE([ASM_X86],
 AS_IF([test "$host_cpu" = x86_64],            [AC_DEFINE([ASM_X86],                [1], [architecture is x86])])
 
 dnl Features (enabled by default)
-AS_IF([test "$enable_debug"           = yes], [AC_DEFINE([ENABLE_DEBUG],           [1], [enabled debugging])])
+AS_IF([test "$enable_assert"          = yes], [AC_DEFINE([ENABLE_ASSERT],          [1], [enabled assertions])])
 AS_IF([test "$enable_float"           = yes], [AC_DEFINE([ENABLE_FLOAT],           [1], [enabled floating-point arithmetic])])
 AS_IF([test "$enable_werror"          = yes], [AC_DEFINE([ENABLE_WERROR],          [1], [enabled -Werror])])
 
@@ -278,7 +278,7 @@ AS_IF([test "$with_arch_i386"         = yes], [AC_DEFINE([WITH_ARCH_X86],
 AS_IF([test "$with_arch_x86_64"       = yes], [AC_DEFINE([WITH_ARCH_X86],          [1], [with architecture x86])])
 
 dnl Additional
-AS_IF([test "$enable_debug"           = yes], [AC_DEFINE([KERNAUX_DEBUG],          [1], [enabled debugging])])
+AS_IF([test "$enable_assert"          = yes], [AC_DEFINE([KERNAUX_ENABLE_ASSERT],  [1], [enabled assertions])])
 
 
 
diff --git a/examples/assert.c b/examples/assert.c
index d9cdaf3..464439a 100644
--- a/examples/assert.c
+++ b/examples/assert.c
@@ -1,4 +1,4 @@
-#define KERNAUX_DEBUG
+#define KERNAUX_ENABLE_ASSERT
 #include <kernaux/assert.h>
 
 #include <assert.h>
diff --git a/examples/panic.c b/examples/panic.c
index 375e799..b79b29e 100644
--- a/examples/panic.c
+++ b/examples/panic.c
@@ -1,4 +1,4 @@
-#define KERNAUX_DEBUG
+#define KERNAUX_ENABLE_ASSERT
 #include <kernaux/assert.h>
 
 #include <assert.h>
diff --git a/include/kernaux/assert.h b/include/kernaux/assert.h
index 09e0172..2e0c997 100644
--- a/include/kernaux/assert.h
+++ b/include/kernaux/assert.h
@@ -5,7 +5,7 @@
 extern "C" {
 #endif
 
-#ifdef KERNAUX_DEBUG
+#ifdef KERNAUX_ENABLE_ASSERT
 #define KERNAUX_PANIC(msg) (kernaux_assert_do(__FILE__, __LINE__, msg))
 #define KERNAUX_ASSERT(cond) ((cond) ? (void)0 : KERNAUX_PANIC(#cond))
 #else
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 841ab08..e09bb88 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -270,7 +270,7 @@ endif
 # test_ntoa_assert #
 ####################
 
-if ENABLE_DEBUG
+if ENABLE_ASSERT
 if WITH_NTOA
 TESTS += test_ntoa_assert
 test_ntoa_assert_LDADD = $(top_builddir)/libkernaux.la
@@ -296,7 +296,7 @@ endif
 # test_pfa_assert #
 ###################
 
-if ENABLE_DEBUG
+if ENABLE_ASSERT
 if WITH_PFA
 TESTS += test_pfa_assert
 test_pfa_assert_LDADD = $(top_builddir)/libkernaux.la
diff --git a/tests/test_memmap.c b/tests/test_memmap.c
index ff35279..2ddb9e3 100644
--- a/tests/test_memmap.c
+++ b/tests/test_memmap.c
@@ -36,7 +36,7 @@ static void before_assert()
 
 static void expect_assert()
 {
-#ifdef ENABLE_DEBUG
+#ifdef ENABLE_ASSERT
     // cppcheck-suppress assignmentInAssert
     assert(assert_count_ctr == ++assert_count_exp);
     assert(strstr(assert_last_file, "src/memmap.c") != NULL);