diff --git a/.imag-documentation/Cargo.toml b/.imag-documentation/Cargo.toml
index 58070181..217538f8 100644
--- a/.imag-documentation/Cargo.toml
+++ b/.imag-documentation/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 
 [dependencies.libimagbookmark]
diff --git a/.travis.yml b/.travis.yml
index 365c9971..e7098cb1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -20,6 +20,7 @@ before_script:
   export PATH=$HOME/.local/bin:$PATH
 script:
 - |
+  export RUSTFLAGS="-C codegen-units=2"
   if [[ "$TEST_SUITE" == "binaries" ]]; then
     make bin-test
   else # $TEST_SUITE == "libraries"
diff --git a/bin/Cargo.toml b/bin/Cargo.toml
index f49197c7..3c02cd6d 100644
--- a/bin/Cargo.toml
+++ b/bin/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 version = "2.0"
 walkdir = "0.1"
diff --git a/imag-bookmark/Cargo.toml b/imag-bookmark/Cargo.toml
index 61970c3c..3d3a18cf 100644
--- a/imag-bookmark/Cargo.toml
+++ b/imag-bookmark/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 log = "0.3"
diff --git a/imag-counter/Cargo.toml b/imag-counter/Cargo.toml
index 138cd5c3..1c7968b7 100644
--- a/imag-counter/Cargo.toml
+++ b/imag-counter/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 log = "0.3"
diff --git a/imag-diary/Cargo.toml b/imag-diary/Cargo.toml
index 0ec869af..f0a75688 100644
--- a/imag-diary/Cargo.toml
+++ b/imag-diary/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 chrono = "0.2"
 version = "2.0"
diff --git a/imag-link/Cargo.toml b/imag-link/Cargo.toml
index d5153958..bb5ad615 100644
--- a/imag-link/Cargo.toml
+++ b/imag-link/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 semver = "0.5.1"
 clap = "2.*"
diff --git a/imag-notes/Cargo.toml b/imag-notes/Cargo.toml
index 0656c2e6..39ec0f71 100644
--- a/imag-notes/Cargo.toml
+++ b/imag-notes/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 semver = "0.2.1"
 clap = "2.*"
diff --git a/imag-ref/Cargo.toml b/imag-ref/Cargo.toml
index c23cd63b..1e5fb9e6 100644
--- a/imag-ref/Cargo.toml
+++ b/imag-ref/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 semver = "0.5.1"
 clap = "2.*"
diff --git a/imag-store/Cargo.toml b/imag-store/Cargo.toml
index f173fc7e..c23a0201 100644
--- a/imag-store/Cargo.toml
+++ b/imag-store/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 log = "0.3"
diff --git a/imag-tag/Cargo.toml b/imag-tag/Cargo.toml
index 7330e2e1..88a97b9d 100644
--- a/imag-tag/Cargo.toml
+++ b/imag-tag/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 log = "0.3"
diff --git a/imag-todo/Cargo.toml b/imag-todo/Cargo.toml
index 31993f0a..320cfea4 100644
--- a/imag-todo/Cargo.toml
+++ b/imag-todo/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 glob = "0.2.11"
diff --git a/imag-view/Cargo.toml b/imag-view/Cargo.toml
index ce0591cd..a1f5e604 100644
--- a/imag-view/Cargo.toml
+++ b/imag-view/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 log = "0.3"
diff --git a/libimagbookmark/Cargo.toml b/libimagbookmark/Cargo.toml
index 0c50403c..d30bcc0c 100644
--- a/libimagbookmark/Cargo.toml
+++ b/libimagbookmark/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 log = "0.3"
 semver = "0.5"
diff --git a/libimagcounter/Cargo.toml b/libimagcounter/Cargo.toml
index 0551b42e..7478540a 100644
--- a/libimagcounter/Cargo.toml
+++ b/libimagcounter/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 log = "0.3"
 toml = "0.2.*"
diff --git a/libimagdiary/Cargo.toml b/libimagdiary/Cargo.toml
index ec9f02a7..db238f06 100644
--- a/libimagdiary/Cargo.toml
+++ b/libimagdiary/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 chrono = "0.2"
 log = "0.3"
diff --git a/libimagentryfilter/Cargo.toml b/libimagentryfilter/Cargo.toml
index fd320a5f..6f090335 100644
--- a/libimagentryfilter/Cargo.toml
+++ b/libimagentryfilter/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 filters = "0.1.*"
diff --git a/libimagentrylink/Cargo.toml b/libimagentrylink/Cargo.toml
index 69fa4f57..9394bebc 100644
--- a/libimagentrylink/Cargo.toml
+++ b/libimagentrylink/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 itertools = "0.4"
 log = "0.3"
diff --git a/libimagentrylist/Cargo.toml b/libimagentrylist/Cargo.toml
index 794cd814..0f7a73d1 100644
--- a/libimagentrylist/Cargo.toml
+++ b/libimagentrylist/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 log = "0.3"
diff --git a/libimagentrymarkdown/Cargo.toml b/libimagentrymarkdown/Cargo.toml
index 6893a113..914dcfe4 100644
--- a/libimagentrymarkdown/Cargo.toml
+++ b/libimagentrymarkdown/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 log = "0.3"
 hoedown = "5.0.0"
diff --git a/libimagentrytag/Cargo.toml b/libimagentrytag/Cargo.toml
index baee9628..f7f44589 100644
--- a/libimagentrytag/Cargo.toml
+++ b/libimagentrytag/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 log = "0.3"
diff --git a/libimagentryview/Cargo.toml b/libimagentryview/Cargo.toml
index f29d6119..8bf7e59e 100644
--- a/libimagentryview/Cargo.toml
+++ b/libimagentryview/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 log = "0.3"
 toml = "0.2.*"
diff --git a/libimagerror/Cargo.toml b/libimagerror/Cargo.toml
index d1394bd1..2930f5c0 100644
--- a/libimagerror/Cargo.toml
+++ b/libimagerror/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 log = "0.3"
 ansi_term = "0.9"
diff --git a/libimaginteraction/Cargo.toml b/libimaginteraction/Cargo.toml
index e6a4a2e7..044fe9b0 100644
--- a/libimaginteraction/Cargo.toml
+++ b/libimaginteraction/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 ansi_term = "0.9.*"
 clap = "2.*"
diff --git a/libimagnotes/Cargo.toml b/libimagnotes/Cargo.toml
index 36d8e13e..357d5530 100644
--- a/libimagnotes/Cargo.toml
+++ b/libimagnotes/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 semver = "0.5"
 log = "0.3"
diff --git a/libimagref/Cargo.toml b/libimagref/Cargo.toml
index e1d749fd..df218e45 100644
--- a/libimagref/Cargo.toml
+++ b/libimagref/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 itertools = "0.5"
 log = "0.3"
diff --git a/libimagrt/Cargo.toml b/libimagrt/Cargo.toml
index d72d173b..129362d0 100644
--- a/libimagrt/Cargo.toml
+++ b/libimagrt/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 env_logger = "0.3"
diff --git a/libimagstore/Cargo.toml b/libimagstore/Cargo.toml
index 53c23950..9a55173d 100644
--- a/libimagstore/Cargo.toml
+++ b/libimagstore/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 fs2 = "0.3"
 glob = "0.2.11"
diff --git a/libimagstorestdhook/Cargo.toml b/libimagstorestdhook/Cargo.toml
index 483fa1cf..82c286c3 100644
--- a/libimagstorestdhook/Cargo.toml
+++ b/libimagstorestdhook/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 toml = "0.2.*"
 log = "0.3"
diff --git a/libimagtimeui/Cargo.toml b/libimagtimeui/Cargo.toml
index 8f07c241..b59a16a0 100644
--- a/libimagtimeui/Cargo.toml
+++ b/libimagtimeui/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 clap = "2.*"
 lazy_static = "0.2"
diff --git a/libimagtodo/Cargo.toml b/libimagtodo/Cargo.toml
index 7b2c9138..d46edd3f 100644
--- a/libimagtodo/Cargo.toml
+++ b/libimagtodo/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 semver = "0.2"
 task-hookrs = "0.2.2"
diff --git a/libimagutil/Cargo.toml b/libimagutil/Cargo.toml
index 7b37d19e..2f7c392a 100644
--- a/libimagutil/Cargo.toml
+++ b/libimagutil/Cargo.toml
@@ -13,6 +13,9 @@ documentation = "https://matthiasbeyer.github.io/imag/imag_documentation/index.h
 repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
+[profile.dev]
+codegen-units = 2
+
 [dependencies]
 url = "1.2"
 boolinator = "2.4.0"