diff --git a/.gitea/workflows/build.yaml b/.gitea/workflows/build.yaml
index 3651e89..1b9a55d 100644
--- a/.gitea/workflows/build.yaml
+++ b/.gitea/workflows/build.yaml
@@ -57,20 +57,9 @@ jobs:
           hash -r
           csc -version
 
-      - name: Install eggs
-        run: |
-          set -eu
-          mkdir -p .eggs
-          repo="$(chicken-install -repository)"
-          echo "CHICKEN_INSTALL_REPOSITORY=${PWD}/.eggs" >> "$GITHUB_ENV"
-          echo "CHICKEN_REPOSITORY_PATH=${PWD}/.eggs:${repo}" >> "$GITHUB_ENV"
-          export CHICKEN_INSTALL_REPOSITORY="${PWD}/.eggs"
-          export CHICKEN_REPOSITORY_PATH="${PWD}/.eggs:${repo}"
-          # shellcheck disable=SC2046
-          chicken-install $(cat dependencies.txt)
-
+      # Eggs are pinned in eggs.lock and installed by the Makefile into .eggs/.
       - name: Build sexc
-        run: make sexc && ./sexc --help
+        run: make && ./sexc --help
 
       - name: Run tests
-        run: make run-tests
+        run: make check
diff --git a/.gitignore b/.gitignore
index e50abab..d588d9c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,7 @@
+# Project-local Chicken egg repository
+/.eggs
+
+# Compilation artifacts
 *.o
 *.import.scm
 *.link
diff --git a/Makefile b/Makefile
index 76857fa..ebb1898 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,6 @@
-CHICKEN_C = csc
+CHICKEN_C ?= csc
+CHICKEN_INSTALL ?= chicken-install
+CHICKEN_STATUS ?= chicken-status
 CSC_FLAGS += -K prefix -static
 # What and why:
 # -emit-all-import-libraries: Emit import-libraries for all defined modules.
@@ -12,17 +14,44 @@ CSC_FLAGS += -K prefix -static
 #     error.
 # -c: Stop after compilation to object files. This one is obvious.
 
+# GNU directory variables. Command line overrides, e.g.
+#   make prefix=$(HOME)/.local install
+#   make DESTDIR=/tmp/stage prefix=/usr install
+prefix = /usr/local
+exec_prefix = $(prefix)
+bindir = $(exec_prefix)/bin
+INSTALL = install
+INSTALL_PROGRAM = $(INSTALL)
+
 MODULE_FLAGS = -emit-all-import-libraries -module-registration -c
 
 # Order matters, since module check correctness on compilation
 MODULES = utils types sex-macros reader sex-modules semen sex-fmt-c fmt-c-writer sexc
 OBJ = $(MODULES:%=%.o)
 
-sexc: $(OBJ) main.scm
+DEPSFILE = dependencies.txt
+DEPSLOCK = eggs.lock
+EGGS_DIR := $(abspath .eggs)
+
+# Compiler's own repository (types.db, chicken.*), ignoring ambient venv vars.
+SYSTEM_CHICKEN_REPO := $(shell env -u CHICKEN_INSTALL_REPOSITORY -u CHICKEN_REPOSITORY_PATH -u CHICKEN_EGG_CACHE -u CHICKEN_INSTALL_PREFIX $(CHICKEN_INSTALL) -repository 2>/dev/null)
+CHICKEN_ABI := $(notdir $(SYSTEM_CHICKEN_REPO))
+EGGS_STAMP := $(EGGS_DIR)/.installed-$(CHICKEN_ABI)
+
+export CHICKEN_EGG_CACHE := $(EGGS_DIR)/cache
+export CHICKEN_INSTALL_REPOSITORY := $(EGGS_DIR)
+export CHICKEN_INSTALL_PREFIX := $(EGGS_DIR)
+export CHICKEN_REPOSITORY_PATH := $(EGGS_DIR):$(SYSTEM_CHICKEN_REPO)
+
+all: sexc
+
+sexc: $(EGGS_STAMP) $(OBJ) main.scm
 	$(CHICKEN_C) $(CSC_FLAGS) main.scm -o sexc-tmp -link sexc
         # otherwise csc hangs, probably because it tries to compile to sexc.o first
 	mv sexc-tmp sexc
 
+$(OBJ): $(EGGS_STAMP)
+
 #------------------------------------------------------------------
 
 utils.o: utils.module.scm utils.scm
@@ -53,11 +82,11 @@ sexc.o: sexc.module.scm types.o sexc.scm fmt-c-writer.o sex-macros.o sex-modules
 	$(CHICKEN_C) $(CSC_FLAGS) $(MODULE_FLAGS) sexc.module.scm -o sexc.o -unit sexc -link fmt-c-writer,sex-macros,sex-modules,reader,semen,types,utils
 
 # Unit testing
-sex-tests:
+sex-tests: $(EGGS_STAMP)
 	$(MAKE) -C ./tests sex-tests
 	cp ./tests/sex-tests ./
 
-sextest:
+sextest: $(EGGS_STAMP)
 	$(MAKE) -C ./tools/sextest sextest
 	cp ./tools/sextest/sextest .
 
@@ -71,14 +100,51 @@ check-modules: sexc
 check-exit-code: sexc
 	@$(MAKE) --no-print-directory -C ./tests/exit-code check SEXC=../../sexc
 
-run-tests: sexc sex-tests sextest
+check run-tests: sexc sex-tests sextest
 	./sex-tests && ./sextest --sexc=./sexc $(SEX_TEST_PROGRAMS:%=./tests/sex-programs/%.sex) && $(MAKE) check-modules && $(MAKE) check-exit-code
 
+install: all installdirs
+	$(INSTALL_PROGRAM) sexc $(DESTDIR)$(bindir)/sexc
+
+install-strip:
+	$(MAKE) INSTALL_PROGRAM='$(INSTALL_PROGRAM) -s' install
+
+installdirs:
+	$(INSTALL) -d $(DESTDIR)$(bindir)
+
+uninstall:
+	rm -f $(DESTDIR)$(bindir)/sexc
+
+# eggs.lock is the pin file (chicken-status -list). Install from it;
+# do not float versions on a normal build. Regenerating the lock:
+#   make deps-update
+$(EGGS_STAMP): $(DEPSLOCK)
+	mkdir -p $(CHICKEN_EGG_CACHE)
+	$(CHICKEN_INSTALL) -force -from-list $(DEPSLOCK)
+	touch $@
+
+deps: $(EGGS_STAMP)
+
+deps-update: $(DEPSFILE)
+	rm -rf $(EGGS_DIR)
+	mkdir -p $(CHICKEN_EGG_CACHE)
+	$(CHICKEN_INSTALL) -force $$(cat $(DEPSFILE))
+	CHICKEN_REPOSITORY_PATH=$(EGGS_DIR) $(CHICKEN_STATUS) -list | sort > $(DEPSLOCK).tmp
+	mv $(DEPSLOCK).tmp $(DEPSLOCK)
+	touch $(EGGS_STAMP)
+
 clean:
 	rm -f $(OBJ) main.o
 	rm -f *.import.scm
 	rm -f *.link
 	rm -f sexc sex-tests sextest
+	$(MAKE) -C ./tests clean
 	$(MAKE) -C ./tests/modules clean
+	$(MAKE) -C ./tools/sextest clean
 
-.PHONY: clean run-tests sex-tests sextest check-modules check-exit-code
+deps-clean:
+	rm -rf $(EGGS_DIR)
+
+.PHONY: all check run-tests check-modules check-exit-code \
+        install install-strip installdirs uninstall \
+        deps deps-update deps-clean clean sex-tests sextest
diff --git a/Readme.org b/Readme.org
index 9e0b73a..e335085 100644
--- a/Readme.org
+++ b/Readme.org
@@ -12,16 +12,46 @@ Sex is statically typed, compiled general purpose language.
 First, get yourself a Chicken, then, some Chicken deps. You also will
 need a C compiler.
 
-** Install Chicken Eggs
-Tip: there's a way to make Chicken install eggs non-globally. You need
-to export ~CHICKEN_INSTALL_REPOSITORY~ and ~CHICKEN_REPOSITORY_PATH~
-environment variables. Refer to the documentation for more info:
-https://wiki.call-cc.org/man/5/Extension%20tools#changing-the-repository-location
-
-~chicken-install `cat dependencies.txt`~
+Eggs are installed into a project-local ~.eggs/~ repository; they do not
+touch the Chicken system repository.
 
 ** Compilation
-~make~
+#+begin_src sh
+  make
+#+end_src
+
+That installs pinned eggs from ~eggs.lock~ into ~.eggs/~ if needed, then
+builds ~sexc~. ~dependencies.txt~ is the unpinned request list. To
+refresh ~eggs.lock~ after changing it:
+
+#+begin_src sh
+  make deps-update
+#+end_src
+
+** Static compilation
+The default ~CSC_FLAGS~ include ~-static~, so ~sexc~ does not need
+~.eggs~ at runtime and ~make install~ stays relocatable. Chicken must
+provide ~libchicken.a~ (E.g. for gentoo: ~dev-scheme/chicken~ with
+~static-libs~ use flag).
+
+To link dynamically instead (the binary will look for eggs under this
+tree's ~.eggs~ path):
+
+#+begin_src sh
+  make CSC_FLAGS='-K prefix'
+#+end_src
+
+** Installation
+GNU directory variables: ~prefix~, ~exec_prefix~, ~bindir~, ~DESTDIR~.
+
+#+begin_src sh
+  # default installation (/usr/local/bin/)
+  make install
+  # customize the prefix (installs to ~/.local/bin)
+  make prefix=$(HOME)/.local install
+  # staged install for packaging
+  make DESTDIR=/tmp/stage prefix=/usr install
+#+end_src
 
 * Usage
 ** Summary
diff --git a/eggs.lock b/eggs.lock
new file mode 100644
index 0000000..aeca254
--- /dev/null
+++ b/eggs.lock
@@ -0,0 +1,8 @@
+(brev-separate "1.100")
+(fmt "0.8.14")
+(getopt-long "4.0")
+(matchable "1.2")
+(srfi-1 "0.5.1")
+(srfi-13 "0.3.8")
+(srfi-69 "0.5.3")
+(test "1.3")
diff --git a/tests/Makefile b/tests/Makefile
index b40a19e..7297715 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -46,3 +46,5 @@ clean:
 	rm -f *.import.scm
 	rm -f *.link
 	rm -f sex-tests
+
+.PHONY: clean