manual: build action -> build task

after discussing this with multiple people, I'm convinced that "build
task" is more precise: a derivation is not an action, but inert until it
is built. also it's easier to pronounce.

proposal: use "build task" for the generic concept "description of how
to derive new files from the contents of existing files". then it will
be easier to distinguish what we mean by "derivation" (a specific data
structure and Nix language value type) and "store derivation" (a
serialisation of a derivation into a file in the Nix store).

5 files changed, 8 insertions, 8 deletions

diff --git a/doc/manual/src/command-ref/nix-daemon.md b/doc/manual/src/command-ref/nix-daemon.md
index e91cb01dd..04b483be3 100644
--- a/doc/manual/src/command-ref/nix-daemon.md
+++ b/doc/manual/src/command-ref/nix-daemon.md
@@ -8,6 +8,6 @@
 
 # Description
 
-The Nix daemon is necessary in multi-user Nix installations. It performs
-build actions and other operations on the Nix store on behalf of
+The Nix daemon is necessary in multi-user Nix installations. It runs
+build tasks and other operations on the Nix store on behalf of
 unprivileged users.
diff --git a/doc/manual/src/command-ref/nix-store.md b/doc/manual/src/command-ref/nix-store.md
index ecd838e8d..1251888e9 100644
--- a/doc/manual/src/command-ref/nix-store.md
+++ b/doc/manual/src/command-ref/nix-store.md
@@ -71,7 +71,7 @@ paths. Realisation is a somewhat overloaded term:
     outputs are already valid, in which case we are done
     immediately. Otherwise, there may be [substitutes](../glossary.md)
     that produce the outputs (e.g., by downloading them). Finally, the
-    outputs can be produced by performing the build action described
+    outputs can be produced by running the build task described
     by the derivation.
 
   - If the store path is not a derivation, realisation ensures that the
diff --git a/doc/manual/src/glossary.md b/doc/manual/src/glossary.md
index 70a0eb994..b13709f8a 100644
--- a/doc/manual/src/glossary.md
+++ b/doc/manual/src/glossary.md
@@ -1,7 +1,7 @@
 # Glossary
 
   - [derivation]{#gloss-derivation}\
-    A description of a build action. The result of a derivation is a
+    A description of a build task. The result of a derivation is a
     store object. Derivations are typically specified in Nix expressions
     using the [`derivation` primitive](language/derivations.md). These are
     translated into low-level *store derivations* (implicitly by
@@ -53,8 +53,8 @@
     A file that is an immediate child of the Nix store directory. These
     can be regular files, but also entire directory trees. Store objects
     can be sources (objects copied from outside of the store),
-    derivation outputs (objects produced by running a build action), or
-    derivations (files describing a build action).
+    derivation outputs (objects produced by running a build task), or
+    derivations (files describing a build task).
 
   - [input-addressed store object]{#gloss-input-addressed-store-object}\
     A store object produced by building a
diff --git a/doc/manual/src/introduction.md b/doc/manual/src/introduction.md
index d87487a07..b54346db8 100644
--- a/doc/manual/src/introduction.md
+++ b/doc/manual/src/introduction.md
@@ -104,7 +104,7 @@ a currently running program.
 
 Packages are built from _Nix expressions_, which is a simple
 functional language.  A Nix expression describes everything that goes
-into a package build action (a “derivation”): other packages, sources,
+into a package build task (a “derivation”): other packages, sources,
 the build script, environment variables for the build script, etc.
 Nix tries very hard to ensure that Nix expressions are
 _deterministic_: building a Nix expression twice should yield the same
diff --git a/doc/manual/src/language/derivations.md b/doc/manual/src/language/derivations.md
index 3391ec0d8..043a38191 100644
--- a/doc/manual/src/language/derivations.md
+++ b/doc/manual/src/language/derivations.md
@@ -1,7 +1,7 @@
 # Derivations
 
 The most important built-in function is `derivation`, which is used to
-describe a single derivation (a build action). It takes as input a set,
+describe a single derivation (a build task). It takes as input a set,
 the attributes of which specify the inputs of the build.
 
   - There must be an attribute named [`system`]{#attr-system} whose value must be a