diff --git a/.gitignore b/.gitignore
index 07d0408..dc90bc2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,3 +6,4 @@ vendor
 out
 config.yaml
 .DS_Store
+results
diff --git a/build/build.sh b/build/build.sh
deleted file mode 100755
index e319d6e..0000000
--- a/build/build.sh
+++ /dev/null
@@ -1,111 +0,0 @@
-#!/bin/bash
-#
-# GoLang cross-compile snippet for Go 1.6+ based loosely on Dave Chaney's cross-compile script:
-# http://dave.cheney.net/2012/09/08/an-introduction-to-cross-compilation-with-go
-#
-# To use:
-#
-#   $ cd ~/path-to/my-awesome-project
-#   $ go-build-all
-#
-# Features:
-#
-#   * Cross-compiles to multiple machine types and architectures.
-#   * Uses the current directory name as the output name...
-#     * ...unless you supply an source file: $ go-build-all main.go
-#   * Windows binaries are named .exe.
-#   * ARM v5, v6, v7 and v8 (arm64) support
-#
-# ARM Support:
-#
-# You must read https://github.com/golang/go/wiki/GoArm for the specifics of running
-# Linux/BSD-style kernels and what kernel modules are needed for the target platform.
-# While not needed for cross-compilation of this script, you're users will need to ensure
-# the correct modules are included.
-#
-# Requirements:
-#
-#   * GoLang 1.6+ (for mips and ppc), 1.5 for non-mips/ppc.
-#   * CD to directory of the binary you are compiling. $PWD is used here.
-#
-# For 1.4 and earlier, see http://dave.cheney.net/2012/09/08/an-introduction-to-cross-compilation-with-go
-#
-
-# This PLATFORMS list is refreshed after every major Go release.
-# Though more platforms may be supported (freebsd/386), they have been removed
-# from the standard ports/downloads and therefore removed from this list.
-#
-PLATFORMS="darwin/amd64" # amd64 only as of go1.5
-PLATFORMS="$PLATFORMS windows/amd64 windows/386" # arm compilation not available for Windows
-PLATFORMS="$PLATFORMS linux/amd64 linux/386"
-PLATFORMS="$PLATFORMS linux/ppc64 linux/ppc64le"
-PLATFORMS="$PLATFORMS linux/mips64 linux/mips64le" # experimental in go1.6
-PLATFORMS="$PLATFORMS freebsd/amd64"
-PLATFORMS="$PLATFORMS netbsd/amd64" # amd64 only as of go1.6
-PLATFORMS="$PLATFORMS openbsd/amd64" # amd64 only as of go1.6
-PLATFORMS="$PLATFORMS dragonfly/amd64" # amd64 only as of go1.5
-PLATFORMS="$PLATFORMS plan9/amd64 plan9/386" # as of go1.4
-PLATFORMS="$PLATFORMS solaris/amd64" # as of go1.3
-
-# ARMBUILDS lists the platforms that are currently supported.  From this list
-# we generate the following architectures:
-#
-#   ARM64 (aka ARMv8) <- only supported on linux and darwin builds (go1.6)
-#   ARMv7
-#   ARMv6
-#   ARMv5
-#
-# Some words of caution from the master:
-#
-#   @dfc: you'll have to use gomobile to build for darwin/arm64 [and others]
-#   @dfc: that target expects that you're bulding for a mobile phone
-#   @dfc: iphone 5 and below, ARMv7, iphone 3 and below ARMv6, iphone 5s and above arm64
-# 
-PLATFORMS_ARM="linux freebsd netbsd"
-
-##############################################################
-# Shouldn't really need to modify anything below this line.  #
-##############################################################
-
-type setopt >/dev/null 2>&1
-
-SCRIPT_NAME=`basename "$0"`
-FAILURES=""
-SOURCE_FILE=`echo $@ | sed 's/\.go//'`
-CURRENT_DIRECTORY=${PWD##*/}
-OUTPUT=${SOURCE_FILE:-$CURRENT_DIRECTORY} # if no src file given, use current dir name
-OUTDIR="bin"
-
-for PLATFORM in $PLATFORMS; do
-  GOOS=${PLATFORM%/*}
-  GOARCH=${PLATFORM#*/}
-  BIN_FILENAME="${OUTDIR}/${OUTPUT}-${GOOS}-${GOARCH}"
-  if [[ "${GOOS}" == "windows" ]]; then BIN_FILENAME="${BIN_FILENAME}.exe"; fi
-  CMD="GOOS=${GOOS} GOARCH=${GOARCH} go build -o ${BIN_FILENAME} $@"
-  echo "${CMD}"
-  eval $CMD || FAILURES="${FAILURES} ${PLATFORM}"
-done
-
-# ARM builds
-if [[ $PLATFORMS_ARM == *"linux"* ]]; then 
-  CMD="GOOS=linux GOARCH=arm64 go build -o ${OUTPUT}-linux-arm64 $@"
-  echo "${CMD}"
-  eval $CMD || FAILURES="${FAILURES} ${PLATFORM}"
-fi
-for GOOS in $PLATFORMS_ARM; do
-  GOARCH="arm"
-  # build for each ARM version
-  for GOARM in 7 6 5; do
-    BIN_FILENAME="${OUTPUT}-${GOOS}-${GOARCH}${GOARM}"
-    CMD="GOARM=${GOARM} GOOS=${GOOS} GOARCH=${GOARCH} go build -o ${BIN_FILENAME} $@"
-    echo "${CMD}"
-    eval "${CMD}" || FAILURES="${FAILURES} ${GOOS}/${GOARCH}${GOARM}" 
-  done
-done
-
-# eval errors
-if [[ "${FAILURES}" != "" ]]; then
-  echo ""
-  echo "${SCRIPT_NAME} failed on: ${FAILURES}"
-  exit 1
-fi
diff --git a/config.go b/config.go
index 6dd79b0..cffc022 100644
--- a/config.go
+++ b/config.go
@@ -38,7 +38,10 @@ type Config struct {
 	OutDir            string `yaml:"-"`
 	ParallelDownloads int    `yaml:"parallelDownloads"`
 	MaxWaitTime       int    `yaml:"waitTime"`
-	Rate              int    `yaml:"rate"`
+	Rate              int             `yaml:"rate"`
+	IncludeSlugs      map[string]bool `yaml:"-"`
+	ExcludeSlugs      map[string]bool `yaml:"-"`
+	PrintSlugs        bool            `yaml:"-"`
 }
 
 func ParseConfig(filename string) (*Config, error) {
diff --git a/include.txt b/include.txt
new file mode 100644
index 0000000..ceead85
--- /dev/null
+++ b/include.txt
@@ -0,0 +1,2 @@
+silent-addition
+the-magic-mirror-2-1
diff --git a/main.go b/main.go
index 88315c1..2af537b 100644
--- a/main.go
+++ b/main.go
@@ -25,9 +25,12 @@
 package main
 
 import (
+	"bufio"
 	"flag"
+	"fmt"
 	"os"
 	"path/filepath"
+	"strings"
 	"sync"
 	"time"
 
@@ -70,8 +73,25 @@ func exec(cfg *Config) {
 		log.Fatal(err)
 	}
 
+	if cfg.PrintSlugs {
+		for _, q := range qs.Models {
+			fmt.Println(q.Slug)
+		}
+		return
+	}
+
 	var subs = make(map[string]SubmissionMap)
+
 	for _, q := range qs.Models {
+		if len(cfg.IncludeSlugs) > 0 && !cfg.IncludeSlugs[q.Slug] {
+			log.Debugf("skipping challenge %s (not in include list)", q.Slug)
+			continue
+		}
+		if len(cfg.ExcludeSlugs) > 0 && cfg.ExcludeSlugs[q.Slug] {
+			log.Infof("skipping challenge %s (in exclude list)", q.Slug)
+			continue
+		}
+
 		s, err := GetAllSubmissions(client, cfg, q.Slug)
 		if err != nil {
 			log.Fatalf("error fetching submissions, %v", err)
@@ -146,10 +166,34 @@ func exec(cfg *Config) {
 	log.Info("finished executing")
 }
 
+func readSlugsFromFile(path string) (map[string]bool, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	slugs := make(map[string]bool)
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		text := strings.TrimSpace(scanner.Text())
+		if text != "" {
+			slugs[text] = true
+		}
+	}
+	return slugs, scanner.Err()
+}
+
 func main() {
 	var configPath string
+	var printSlugs bool
+	var includeFile string
+	var excludeFile string
 
 	flag.StringVar(&configPath, "config", "config.yaml", "Provide config for the tool")
+	flag.BoolVar(&printSlugs, "print-slugs", false, "Print all challenge slugs and exit")
+	flag.StringVar(&includeFile, "include", "", "Path to file containing slugs to include (one per line)")
+	flag.StringVar(&excludeFile, "exclude", "", "Path to file containing slugs to exclude (one per line)")
 	flag.Parse()
 
 	cfg, err := ParseConfig(configPath)
@@ -157,6 +201,24 @@ func main() {
 		log.Fatal(err)
 	}
 
+	cfg.PrintSlugs = printSlugs
+
+	if includeFile != "" {
+		slugs, err := readSlugsFromFile(includeFile)
+		if err != nil {
+			log.Fatalf("error reading include file: %v", err)
+		}
+		cfg.IncludeSlugs = slugs
+	}
+
+	if excludeFile != "" {
+		slugs, err := readSlugsFromFile(excludeFile)
+		if err != nil {
+			log.Fatalf("error reading exclude file: %v", err)
+		}
+		cfg.ExcludeSlugs = slugs
+	}
+
 	// create output directory with current time
 	cfg.OutDir = filepath.Join(filepath.FromSlash(cfg.Output), time.Now().Format("2006-01-02-15-04"))