diff --git a/.gitignore b/.gitignore
index 356f27e..e45ea04 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,5 @@
 # general ignore patterns
 */bin/*
 
+# set 1 ignores
+set1/aes-libs/*
diff --git a/set1/Makefile b/set1/Makefile
index 32e47b9..cc27bd7 100644
--- a/set1/Makefile
+++ b/set1/Makefile
@@ -2,16 +2,30 @@ CC      = gcc
 CFLAGS  = -Wall -Wpedantic -Wextra -std=c99 -fstack-protector-all \
           -fdiagnostics-color=auto
 DEBUG   = -0g -ggdb
-LINK    = 
+LINK    =
+LIB_INC =
 SRC_DIR = src
 OUT_DIR = bin
-TARGETS = base64 fixed-xor char-freq-analize
+TARGETS = base64 fixed-xor char-freq-analyze repeating-key-xor aes-ecb
 
 
 all: $(TARGETS)
 
+# TODO toggle mbedtls or tiny-AES-c
+#EXT_INCLUDES = -Iaes-libs/mbedtls/include/
+#EXT_LIBS     = -Laes-libs/mbedtls/library
+#LDLIBS       = -lmbedcrypto
+#
+EXT_INCLUDES = -Iaes-libs/tiny-AES-c
+#EXT_LIBS     = -Laes-libs/tiny-AES-c
+#LDLIBS       = -laes
+
+#%: $(SRC_DIR)/%.c
 %: $(SRC_DIR)/%.c
-	$(CC) $(CFLAGS) $(LINK) $< -o $(OUT_DIR)/$@
+	$(CC) $(CFLAGS) -o $(OUT_DIR)/$@ $<
+
+aes-ecb: $(SRC_DIR)/aes-ecb.c
+	$(CC) $(CFLAGS) $(EXT_INCLUDES) $(EXT_LIBS) -o $(OUT_DIR)/$@ $< $(LDLIBS)
 
 clean:
 	$(RM) *.o $(OUT_DIR)/*
diff --git a/set1/README.md b/set1/README.md
new file mode 100644
index 0000000..debfe6b
--- /dev/null
+++ b/set1/README.md
@@ -0,0 +1,28 @@
+# Set 1
+
+Note: may need to `pip install jinja2` in order to `make` mbedtls
+
+### Challenge 1: Convert hex to base64
+Provided by base64.c
+
+### Challenge 2: Fixed XOR
+Provided by fixed-key-xor.c
+
+### Challenge 3: Single-byte XOR cipher
+Provided by ch3-brute-force.c and char-freq-analyze.c
+
+### Challenge 4: Detect single-character XOR
+
+
+### Challenge 5: Implement repeating-key XOR
+Provided by repeating-key-xor.c
+
+### Challenge 6: Break repeating-key XOR
+
+
+### Challenge 7: AES in ECB mode
+
+
+### Challenge 8: Detect AES in ECB mode
+
+
diff --git a/set1/src/char-freq-analyze.c b/set1/src/char-freq-analyze.c
index 2aa7a8e..98cf44a 100644
--- a/set1/src/char-freq-analyze.c
+++ b/set1/src/char-freq-analyze.c
@@ -19,7 +19,7 @@ int main()
 
 	for (i = 0; i < sizeof(byte_freq); ++i) {
 		if (byte_freq[i] != 0) {
-			printf("%x occurs %d times\n", i, byte_freq[i]);
+			printf("%lx occurs %d times\n", i, byte_freq[i]);
 		}
 	}