diff --git a/shell-completion/Makefile b/shell-completion/Makefile
index b983ec2f4..d821ec213 100644
--- a/shell-completion/Makefile
+++ b/shell-completion/Makefile
@@ -4,9 +4,32 @@
 # get parallel jobs.
 MAKEFLAGS += --jobs=$(shell nproc 2>/dev/null || printf 8)
 
-all: hledger-completion.bash
+# Parse hledger's help and output all commands and command aliases in
+# parenthesis. Do not output single letter command aliases, it's not useful.
+COMMANDS_TMP := commands.tmp
 
-COMMANDS := $(sort $(shell hledger | ./output-commands.sh | grep -v ^hledger | sort -u) ui web api)
+define PARSE_COMMANDS :=
+hledger > $(COMMANDS_TMP) ;
+{ \
+	sed -rn 's/^\s+([a-z][-a-z]+)\s+.*/\1/p' $(COMMANDS_TMP) ; \
+	sed -rn 's/^\s+[a-z][-a-z]+\s+\(([a-z][ ,a-z]+)\).*/\1/p' $(COMMANDS_TMP) | \
+	sed 's/\s*,\s*/\n/g' | \
+	sed '/^.$$/d' ; \
+} | sed '/^hledger/d' | sort -u
+endef
+
+# Parse hledger's help and output long options. Do not propose single letter
+# completions. Options requiring an argument make that explicit by appending the
+# equal sign (=)
+define PARSE_OPTIONS :=
+sed -rn '/^\s+-/p' | \
+sed -rn 's/^\s{1,4}(-.)?\s{1,4}(--[a-zA-Z][-_a-zA-Z0-9]+=?).*/\2/p' | \
+sort -u
+endef
+
+EXTENSIONS := ui web api
+
+COMMANDS := $(sort $(shell $(PARSE_COMMANDS)) $(EXTENSIONS))
 CMDOPTFILES := $(foreach CMD,$(COMMANDS),options-$(CMD).txt)
 
 define M4DEPS :=
@@ -19,27 +42,35 @@ generic-options.txt \
 $(CMDOPTFILES)
 endef
 
+all: hledger-completion.bash
+
 hledger-completion.bash: $(M4DEPS)
 	m4 hledger-completion.bash.m4 > $@
 
-generic-options.txt:
-	hledger -h | ./output-options.sh | sort -u > $@
-
 commands.txt:
 	printf "%s\n" $(COMMANDS) > $@
 
 commands-list.txt:
 	printf "%s,"  $(COMMANDS) | sed 's/,$$//' > $@
 
-#query-filters.txt:
-	# The query filters are hard to extract!
-	# hledger help --cat hledger | sed -n '/^QUERIES/,/^[A-Z]/p'
+generic-options.txt:
+	hledger -h | $(PARSE_OPTIONS) > $@
 
 options-%.txt:
-	hledger $* -h | ./output-options.sh $* | sort -u > $@
+	hledger $* -h | $(PARSE_OPTIONS) > $@
 
 .PHONY: clean
 clean:
-	rm -f commands*.txt generic-options.txt options-*.txt
+	rm -f commands*.{txt,tmp} generic-options.txt options-*.txt
 	rm -f hledger-completion.bash
-	rm -rf _{commands,options}.tmp
+
+
+# Basic REGEX debugging targets
+.PHONY: debug-commands debug-options
+
+debug-commands:
+	$(PARSE_COMMANDS)
+
+debug-options: CMD :=
+debug-options:
+	hledger $(CMD) -h | $(PARSE_OPTIONS)
diff --git a/shell-completion/output-commands.sh b/shell-completion/output-commands.sh
deleted file mode 100755
index ae1b67987..000000000
--- a/shell-completion/output-commands.sh
+++ /dev/null
@@ -1,19 +0,0 @@
-#!/bin/bash
-# Output subcommands from man/usage text
-
-set -o errexit -o pipefail -o nounset
-
-main() {
-    declare tmp="_commands.tmp"
-    cat > "$tmp"
-
-    sed -rn 's/^\s+([a-z][-a-z]+)\s+.*/\1/p' "$tmp"
-
-    # Output command aliases in parenthesis:
-    # Do not output single letter command aliases, it's not useful.
-    sed -rn 's/^\s+[a-z][-a-z]+\s+\(([a-z][ ,a-z]+)\).*/\1/p' "$tmp" |
-        sed 's/\s*,\s*/\n/g' |
-        sed '/^.$/d'
-}
-
-main "$@"
diff --git a/shell-completion/output-options.sh b/shell-completion/output-options.sh
deleted file mode 100755
index fbc9e5471..000000000
--- a/shell-completion/output-options.sh
+++ /dev/null
@@ -1,24 +0,0 @@
-#!/bin/bash
-# Output short and long options from man/usage text
-
-set -o errexit -o pipefail -o nounset
-
-main() {
-    declare tmpdir="_options.tmp"
-    declare tmp="${tmpdir}/${1:-generic}"
-
-    mkdir -p "$tmpdir"
-    cat > "$tmp"
-
-    # Do not propose single letter completions. It's not useful, it's noisy
-    # and it makes completion slower:
-    # Display all 200 possibilities? (y or n)
-    # sed -rn 's/.* (-[a-zA-Z0-9]).*/\1/gp' < "$tmp"
-
-    # Options requiring an argument make that explicit by appending
-    # the equal sign (=)
-    sed -rn '/^\s+-/p' "$tmp" |
-        sed -rn 's/^\s{1,4}(-.)?\s{1,4}(--[a-zA-Z][-_a-zA-Z0-9]+=?).*/\2/p'
-}
-
-main "$@"