diff --git a/bin/hcl.fish b/bin/hcl.fish
new file mode 100755
index 0000000..f2a319d
--- /dev/null
+++ b/bin/hcl.fish
@@ -0,0 +1,50 @@
+function __fish_hcl_arg_count
+    set -l cmd (commandline -opc)
+    if [ (count $cmd) -eq $argv[1] ]
+        return 0
+    end
+    return 1
+end
+
+function __fish_hcl_customers
+    hcl tasks | awk -F "\t" '{ split($1,a," "); split($2,b," - "); print a[1] "\t" b[1],"-",b[2] }' | sort -u
+end
+
+function __fish_hcl_tasks
+    set -l cmd (commandline -opc)
+    set -l customer $cmd[4]
+    hcl tasks | grep "^$customer" | awk -F "\t" '{ split($1,a," "); split($2,b," - "); print a[2] "\t" b[3] }'
+end
+
+function __fish_hcl_aliases
+    hcl aliases | sed -e 's/, /\n/g'
+end
+
+complete -c hcl -f
+
+complete -c hcl -f -s r -l reauth -d 'Force refresh of auth details'
+complete -c hcl -f -s c -l changelog -d 'Review the HCl changelog'
+complete -c hcl -f -s v -l version -d 'Print version and exit'
+complete -c hcl -f -s h -l help -d 'Show the help message'
+
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a tasks -d 'show all available tasks'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a alias -d 'create a task alias'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a unalias -d 'remove a task alias'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a aliases -d 'list task aliases'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a start -d 'start a task using an alias'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a stop -d 'stop a running timer'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a note -d 'add a line to a running timer'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a log -d 'log a task and time without leaving a timer running'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a resume -d 'resume the last stopped timer or a specific task'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a 'cancel nvm oops' -d 'delete the current or last running timer'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a show -d 'display the daily timesheet'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a config -d 'show your current credentials'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a status -d 'display Harvest service status'
+complete -c hcl -n '__fish_hcl_arg_count 1' -f -a '(__fish_hcl_aliases)' -d 'start work on aliased task'
+
+complete -c hcl -n '__fish_seen_subcommand_from start; and __fish_hcl_arg_count 2' -f -a '(__fish_hcl_aliases)'
+complete -c hcl -n '__fish_seen_subcommand_from resume; and __fish_hcl_arg_count 2' -f -a '(__fish_hcl_aliases)'
+complete -c hcl -n '__fish_seen_subcommand_from log; and __fish_hcl_arg_count 2' -f -a '(__fish_hcl_aliases)'
+
+complete -c hcl -n '__fish_seen_subcommand_from alias; and __fish_hcl_arg_count 3' -f -a '(__fish_hcl_customers)'
+complete -c hcl -n '__fish_seen_subcommand_from alias; and __fish_hcl_arg_count 4' -f -a '(__fish_hcl_tasks)'