Install packages to lua_modules/, add to path if found.

.gitignore

@@ -21,12 +21,11 @@ Gemfile.lock
 *.spl
 *.synctex.gz
 
-## EPUB files
-*.epub
+## Lua files
+lua_modules/
 
 ## Emacs files
 auto/
 
 ## Misc build files
 out/
-src/plfa/acknowledgements_epub.md

.travis.yml

@@ -21,6 +21,7 @@ cache:
 addons:
   apt:
     packages:
+      - epubcheck
       - libgmp-dev
       - libicu-dev
       - luarocks

Makefile

@@ -4,6 +4,11 @@ AGDAI := $(shell find . -type f -and \( -path '*/src/*' -or -path '*/courses/*'
 LUA := $(shell find . -type f -and -path '*/epub/*' -and -name '*.lua')
 MARKDOWN := $(subst courses/,out/,$(subst src/,out/,$(subst .lagda.md,.md,$(AGDA))))
 PLFA_DIR := $(shell dirname $(realpath $(lastword $(MAKEFILE_LIST))))
+LUA_MODULES := lua_modules/
+
+ifneq ($(wildcard $(LUA_MODULES)),)
+	LUA_FLAGS += -l epub/set_paths
+endif
 
 ifeq ($(AGDA_STDLIB_VERSION),)
 AGDA_STDLIB_URL := https://agda.github.io/agda-stdlib/
@@ -69,7 +74,7 @@ out/epub/plfa.epub: out/epub/ | $(AGDA) $(LUA) epub/main.css out/epub/acknowledg
 		epub/index.md
 
 out/epub/acknowledgements.md: src/plfa/acknowledgements.md _config.yml
-	lua epub/render-liquid-template.lua _config.yml $< $@
+	lua $(LUA_FLAGS) epub/render-liquid-template.lua _config.yml $< $@
 
 
 # Convert literal Agda to Markdown

epub/set_paths.lua

@@ -0,0 +1,4 @@
+-- set_paths.lua
+local version = _VERSION:match("%d+%.%d+")
+package.path = 'lua_modules/share/lua/' .. version .. '/?.lua;lua_modules/share/lua/' .. version .. '/?/init.lua;' .. package.path
+package.cpath = 'lua_modules/lib/lua/' .. version .. '/?.so;' .. package.cpath