diff --git a/Cargo.lock b/Cargo.lock
index a21237968..fa9249540 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -12,6 +12,30 @@ dependencies = [
  "regex",
 ]
 
+[[package]]
+name = "actors-builtin-car"
+version = "0.1.0"
+dependencies = [
+ "bytes",
+ "color-eyre 0.5.11",
+ "fs-err",
+ "futures-util",
+ "reqwest 0.12.12",
+ "sha2 0.10.8",
+ "tempfile",
+ "tokio",
+]
+
+[[package]]
+name = "actors-umbrella"
+version = "0.1.0"
+dependencies = [
+ "fendermint_actor_activity_tracker",
+ "fendermint_actor_chainmetadata",
+ "fendermint_actor_eam",
+ "fendermint_actor_gas_market_eip1559",
+]
+
 [[package]]
 name = "addr2line"
 version = "0.21.0"
@@ -652,7 +676,7 @@ version = "0.24.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8d9a9bf8b79a749ee0b911b91b671cc2b6c670bdbc7e3dfd537576ddc94bb2a2"
 dependencies = [
- "http",
+ "http 0.2.12",
  "log",
  "url",
 ]
@@ -697,9 +721,9 @@ dependencies = [
  "bitflags 1.3.2",
  "bytes",
  "futures-util",
- "http",
- "http-body",
- "hyper",
+ "http 0.2.12",
+ "http-body 0.4.6",
+ "hyper 0.14.31",
  "itoa",
  "matchit",
  "memchr",
@@ -712,10 +736,10 @@ dependencies = [
  "serde_path_to_error",
  "serde_urlencoded",
  "sha1",
- "sync_wrapper",
+ "sync_wrapper 0.1.2",
  "tokio",
  "tokio-tungstenite 0.20.1",
- "tower",
+ "tower 0.4.13",
  "tower-layer",
  "tower-service",
 ]
@@ -729,8 +753,8 @@ dependencies = [
  "async-trait",
  "bytes",
  "futures-util",
- "http",
- "http-body",
+ "http 0.2.12",
+ "http-body 0.4.6",
  "mime",
  "rustversion",
  "tower-layer",
@@ -1133,8 +1157,8 @@ dependencies = [
  "futures-core",
  "futures-util",
  "hex",
- "http",
- "hyper",
+ "http 0.2.12",
+ "hyper 0.14.31",
  "hyperlocal",
  "log",
  "pin-project-lite",
@@ -1171,6 +1195,16 @@ dependencies = [
  "tinyvec",
 ]
 
+[[package]]
+name = "bstr"
+version = "1.11.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "531a9155a481e2ee699d4f98f43c0ca4ff8ee1bfd55c31e9e98fb29d2b176fe0"
+dependencies = [
+ "memchr",
+ "serde",
+]
+
 [[package]]
 name = "bumpalo"
 version = "3.16.0"
@@ -1251,6 +1285,20 @@ dependencies = [
  "thiserror 1.0.69",
 ]
 
+[[package]]
+name = "cargo_metadata"
+version = "0.19.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8769706aad5d996120af43197bf46ef6ad0fda35216b4505f926a365a232d924"
+dependencies = [
+ "camino",
+ "cargo-platform",
+ "semver",
+ "serde",
+ "serde_json",
+ "thiserror 2.0.3",
+]
+
 [[package]]
 name = "castaway"
 version = "0.2.3"
@@ -1514,6 +1562,21 @@ dependencies = [
  "thiserror 1.0.69",
 ]
 
+[[package]]
+name = "color-eyre"
+version = "0.5.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1f1885697ee8a177096d42f158922251a41973117f6d8a234cee94b9509157b7"
+dependencies = [
+ "backtrace",
+ "color-spantrace 0.1.6",
+ "eyre",
+ "indenter",
+ "once_cell",
+ "owo-colors 1.3.0",
+ "tracing-error 0.1.2",
+]
+
 [[package]]
 name = "color-eyre"
 version = "0.6.3"
@@ -1521,12 +1584,24 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "55146f5e46f237f7423d74111267d4597b59b0dad0ffaf7303bce9945d843ad5"
 dependencies = [
  "backtrace",
- "color-spantrace",
+ "color-spantrace 0.2.1",
  "eyre",
  "indenter",
  "once_cell",
- "owo-colors",
- "tracing-error",
+ "owo-colors 3.5.0",
+ "tracing-error 0.2.1",
+]
+
+[[package]]
+name = "color-spantrace"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6eee477a4a8a72f4addd4de416eb56d54bc307b284d6601bafdee1f4ea462d1"
+dependencies = [
+ "once_cell",
+ "owo-colors 1.3.0",
+ "tracing-core",
+ "tracing-error 0.1.2",
 ]
 
 [[package]]
@@ -1536,9 +1611,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cd6be1b2a7e382e2b98b43b2adcca6bb0e465af0bdd38123873ae61eb17a72c2"
 dependencies = [
  "once_cell",
- "owo-colors",
+ "owo-colors 3.5.0",
  "tracing-core",
- "tracing-error",
+ "tracing-error 0.2.1",
 ]
 
 [[package]]
@@ -2629,7 +2704,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "regex",
- "reqwest",
+ "reqwest 0.11.27",
  "serde",
  "serde_json",
  "syn 2.0.87",
@@ -2661,7 +2736,7 @@ checksum = "82d80cc6ad30b14a48ab786523af33b37f28a8623fc06afd55324816ef18fb1f"
 dependencies = [
  "arrayvec 0.7.6",
  "bytes",
- "cargo_metadata",
+ "cargo_metadata 0.18.1",
  "chrono",
  "const-hex",
  "elliptic-curve 0.13.8",
@@ -2691,7 +2766,7 @@ checksum = "e79e5973c26d4baf0ce55520bd732314328cabe53193286671b47144145b9649"
 dependencies = [
  "chrono",
  "ethers-core",
- "reqwest",
+ "reqwest 0.11.27",
  "semver",
  "serde",
  "serde_json",
@@ -2716,7 +2791,7 @@ dependencies = [
  "futures-locks",
  "futures-util",
  "instant",
- "reqwest",
+ "reqwest 0.11.27",
  "serde",
  "serde_json",
  "thiserror 1.0.69",
@@ -2744,12 +2819,12 @@ dependencies = [
  "futures-timer",
  "futures-util",
  "hashers",
- "http",
+ "http 0.2.12",
  "instant",
  "jsonwebtoken",
  "once_cell",
  "pin-project",
- "reqwest",
+ "reqwest 0.11.27",
  "serde",
  "serde_json",
  "thiserror 1.0.69",
@@ -2956,10 +3031,10 @@ dependencies = [
  "structopt",
  "tendermint 0.31.1",
  "tokio",
- "tower",
+ "tower 0.4.13",
  "tower-abci",
  "tracing",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
 ]
 
 [[package]]
@@ -3048,7 +3123,9 @@ name = "fendermint_actors"
 version = "0.1.0"
 dependencies = [
  "anyhow",
+ "cargo_metadata 0.19.1",
  "cid",
+ "color-eyre 0.5.11",
  "fendermint_actor_activity_tracker",
  "fendermint_actor_chainmetadata",
  "fendermint_actor_eam",
@@ -3058,8 +3135,10 @@ dependencies = [
  "fs-err",
  "fvm_ipld_blockstore",
  "fvm_ipld_encoding",
+ "ignore",
  "num-traits",
  "toml 0.8.19",
+ "tracing",
 ]
 
 [[package]]
@@ -3086,6 +3165,7 @@ dependencies = [
 name = "fendermint_app"
 version = "0.1.0"
 dependencies = [
+ "actors-builtin-car",
  "anyhow",
  "async-stm",
  "async-trait",
@@ -3093,6 +3173,7 @@ dependencies = [
  "cid",
  "fendermint_abci",
  "fendermint_actor_gas_market_eip1559",
+ "fendermint_actors",
  "fendermint_actors_api",
  "fendermint_app_options",
  "fendermint_app_settings",
@@ -3149,11 +3230,11 @@ dependencies = [
  "tendermint-proto 0.31.1",
  "tendermint-rpc",
  "tokio",
- "tower",
+ "tower 0.4.13",
  "tower-abci",
  "tracing",
  "tracing-appender",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
 ]
 
 [[package]]
@@ -3177,7 +3258,7 @@ dependencies = [
  "num-traits",
  "tendermint-rpc",
  "tracing",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
  "url",
 ]
 
@@ -3295,7 +3376,7 @@ dependencies = [
  "tokio",
  "tower-http",
  "tracing",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
 ]
 
 [[package]]
@@ -3406,7 +3487,7 @@ dependencies = [
  "tendermint-rpc",
  "tokio",
  "tracing",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
 ]
 
 [[package]]
@@ -3737,7 +3818,7 @@ dependencies = [
  "thiserror 1.0.69",
  "tokio",
  "tracing",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
 ]
 
 [[package]]
@@ -4536,6 +4617,19 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
 
+[[package]]
+name = "globset"
+version = "0.4.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "15f1ce686646e7f1e19bf7d5533fe443a45dbfb990e00629110797578b42fb19"
+dependencies = [
+ "aho-corasick",
+ "bstr",
+ "log",
+ "regex-automata 0.4.9",
+ "regex-syntax 0.8.5",
+]
+
 [[package]]
 name = "gloo-timers"
 version = "0.2.6"
@@ -4597,7 +4691,26 @@ dependencies = [
  "futures-core",
  "futures-sink",
  "futures-util",
- "http",
+ "http 0.2.12",
+ "indexmap 2.6.0",
+ "slab",
+ "tokio",
+ "tokio-util 0.7.12",
+ "tracing",
+]
+
+[[package]]
+name = "h2"
+version = "0.4.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5017294ff4bb30944501348f6f8e42e6ad28f42c8bbef7a74029aff064a4e3c2"
+dependencies = [
+ "atomic-waker",
+ "bytes",
+ "fnv",
+ "futures-core",
+ "futures-sink",
+ "http 1.2.0",
  "indexmap 2.6.0",
  "slab",
  "tokio",
@@ -4663,7 +4776,7 @@ dependencies = [
  "base64 0.21.7",
  "bytes",
  "headers-core",
- "http",
+ "http 0.2.12",
  "httpdate",
  "mime",
  "sha1",
@@ -4675,7 +4788,7 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e7f66481bfee273957b1f20485a4ff3362987f85b2c236580d81b4eb7a326429"
 dependencies = [
- "http",
+ "http 0.2.12",
 ]
 
 [[package]]
@@ -4863,6 +4976,17 @@ dependencies = [
  "itoa",
 ]
 
+[[package]]
+name = "http"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f16ca2af56261c99fba8bac40a10251ce8188205a4c448fbb745a2e4daa76fea"
+dependencies = [
+ "bytes",
+ "fnv",
+ "itoa",
+]
+
 [[package]]
 name = "http-body"
 version = "0.4.6"
@@ -4870,7 +4994,30 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7ceab25649e9960c0311ea418d17bee82c0dcec1bd053b5f9a66e265a693bed2"
 dependencies = [
  "bytes",
- "http",
+ "http 0.2.12",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "http-body"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1efedce1fb8e6913f23e0c92de8e62cd5b772a67e7b3946df930a62566c93184"
+dependencies = [
+ "bytes",
+ "http 1.2.0",
+]
+
+[[package]]
+name = "http-body-util"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "793429d76616a256bcb62c2a2ec2bed781c8307e797e2598c50010f2bee2544f"
+dependencies = [
+ "bytes",
+ "futures-util",
+ "http 1.2.0",
+ "http-body 1.0.1",
  "pin-project-lite",
 ]
 
@@ -4917,9 +5064,9 @@ dependencies = [
  "futures-channel",
  "futures-core",
  "futures-util",
- "h2",
- "http",
- "http-body",
+ "h2 0.3.26",
+ "http 0.2.12",
+ "http-body 0.4.6",
  "httparse",
  "httpdate",
  "itoa",
@@ -4931,6 +5078,26 @@ dependencies = [
  "want",
 ]
 
+[[package]]
+name = "hyper"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cc2b571658e38e0c01b1fdca3bbbe93c00d3d71693ff2770043f8c29bc7d6f80"
+dependencies = [
+ "bytes",
+ "futures-channel",
+ "futures-util",
+ "h2 0.4.8",
+ "http 1.2.0",
+ "http-body 1.0.1",
+ "httparse",
+ "itoa",
+ "pin-project-lite",
+ "smallvec",
+ "tokio",
+ "want",
+]
+
 [[package]]
 name = "hyper-proxy"
 version = "0.9.1"
@@ -4940,8 +5107,8 @@ dependencies = [
  "bytes",
  "futures",
  "headers",
- "http",
- "hyper",
+ "http 0.2.12",
+ "hyper 0.14.31",
  "hyper-rustls 0.22.1",
  "rustls-native-certs 0.5.0",
  "tokio",
@@ -4958,7 +5125,7 @@ checksum = "5f9f7a97316d44c0af9b0301e65010573a853a9fc97046d7331d7f6bc0fd5a64"
 dependencies = [
  "ct-logs",
  "futures-util",
- "hyper",
+ "hyper 0.14.31",
  "log",
  "rustls 0.19.1",
  "rustls-native-certs 0.5.0",
@@ -4975,13 +5142,31 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ec3efd23720e2049821a693cbc7e65ea87c72f1c58ff2f9522ff332b1491e590"
 dependencies = [
  "futures-util",
- "http",
- "hyper",
+ "http 0.2.12",
+ "hyper 0.14.31",
  "rustls 0.21.12",
  "tokio",
  "tokio-rustls 0.24.1",
 ]
 
+[[package]]
+name = "hyper-rustls"
+version = "0.27.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2d191583f3da1305256f22463b9bb0471acad48a4e534a5218b9963e9c1f59b2"
+dependencies = [
+ "futures-util",
+ "http 1.2.0",
+ "hyper 1.6.0",
+ "hyper-util",
+ "rustls 0.23.16",
+ "rustls-pki-types",
+ "tokio",
+ "tokio-rustls 0.26.1",
+ "tower-service",
+ "webpki-roots 0.26.8",
+]
+
 [[package]]
 name = "hyper-tls"
 version = "0.5.0"
@@ -4989,12 +5174,47 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d6183ddfa99b85da61a140bea0efc93fdf56ceaa041b37d553518030827f9905"
 dependencies = [
  "bytes",
- "hyper",
+ "hyper 0.14.31",
  "native-tls",
  "tokio",
  "tokio-native-tls",
 ]
 
+[[package]]
+name = "hyper-tls"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "70206fc6890eaca9fde8a0bf71caa2ddfc9fe045ac9e5c70df101a7dbde866e0"
+dependencies = [
+ "bytes",
+ "http-body-util",
+ "hyper 1.6.0",
+ "hyper-util",
+ "native-tls",
+ "tokio",
+ "tokio-native-tls",
+ "tower-service",
+]
+
+[[package]]
+name = "hyper-util"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "df2dcfbe0677734ab2f3ffa7fa7bfd4706bfdc1ef393f2ee30184aed67e631b4"
+dependencies = [
+ "bytes",
+ "futures-channel",
+ "futures-util",
+ "http 1.2.0",
+ "http-body 1.0.1",
+ "hyper 1.6.0",
+ "pin-project-lite",
+ "socket2 0.5.7",
+ "tokio",
+ "tower-service",
+ "tracing",
+]
+
 [[package]]
 name = "hyperlocal"
 version = "0.8.0"
@@ -5003,7 +5223,7 @@ checksum = "0fafdf7b2b2de7c9784f76e02c0935e65a8117ec3b768644379983ab333ac98c"
 dependencies = [
  "futures-util",
  "hex",
- "hyper",
+ "hyper 0.14.31",
  "pin-project",
  "tokio",
 ]
@@ -5217,7 +5437,7 @@ dependencies = [
  "log",
  "rtnetlink",
  "smol",
- "system-configuration",
+ "system-configuration 0.5.1",
  "tokio",
  "windows",
 ]
@@ -5232,8 +5452,8 @@ dependencies = [
  "attohttpc",
  "bytes",
  "futures",
- "http",
- "hyper",
+ "http 0.2.12",
+ "hyper 0.14.31",
  "log",
  "rand",
  "tokio",
@@ -5241,6 +5461,22 @@ dependencies = [
  "xmltree",
 ]
 
+[[package]]
+name = "ignore"
+version = "0.4.23"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6d89fd380afde86567dfba715db065673989d6253f42b88179abd3eae47bda4b"
+dependencies = [
+ "crossbeam-deque",
+ "globset",
+ "log",
+ "memchr",
+ "regex-automata 0.4.9",
+ "same-file",
+ "walkdir",
+ "winapi-util",
+]
+
 [[package]]
 name = "im"
 version = "15.1.0"
@@ -5435,7 +5671,7 @@ dependencies = [
  "openssl",
  "prometheus",
  "prometheus_exporter",
- "reqwest",
+ "reqwest 0.11.27",
  "serde",
  "serde_bytes",
  "serde_json",
@@ -5445,7 +5681,7 @@ dependencies = [
  "tokio",
  "tokio-tungstenite 0.18.0",
  "toml 0.7.8",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
  "url",
  "zeroize",
 ]
@@ -5463,7 +5699,7 @@ dependencies = [
  "strum",
  "tracing",
  "tracing-appender",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
 ]
 
 [[package]]
@@ -5485,7 +5721,7 @@ dependencies = [
  "fvm_ipld_encoding",
  "fvm_shared",
  "hex",
- "http",
+ "http 0.2.12",
  "indoc",
  "ipc-api",
  "ipc-observability",
@@ -5498,7 +5734,7 @@ dependencies = [
  "num-derive 0.3.3",
  "num-traits",
  "prometheus",
- "reqwest",
+ "reqwest 0.11.27",
  "serde",
  "serde_bytes",
  "serde_json",
@@ -5575,7 +5811,7 @@ name = "ipc_actors_abis"
 version = "0.1.0"
 dependencies = [
  "anyhow",
- "color-eyre",
+ "color-eyre 0.6.3",
  "ethers",
  "fs-err",
  "fvm_shared",
@@ -6009,7 +6245,7 @@ dependencies = [
  "prost-build",
  "thiserror 1.0.69",
  "tracing",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
  "unsigned-varint 0.7.2",
 ]
 
@@ -7287,6 +7523,12 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b15813163c1d831bf4a13c3610c05c0d03b39feb07f7e09fa234dac9b15aaf39"
 
+[[package]]
+name = "owo-colors"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2386b4ebe91c2f7f51082d4cefa145d030e33a1842a96b12e4885cc3c01f7a55"
+
 [[package]]
 name = "owo-colors"
 version = "3.5.0"
@@ -8403,12 +8645,12 @@ dependencies = [
  "encoding_rs",
  "futures-core",
  "futures-util",
- "h2",
- "http",
- "http-body",
- "hyper",
+ "h2 0.3.26",
+ "http 0.2.12",
+ "http-body 0.4.6",
+ "hyper 0.14.31",
  "hyper-rustls 0.24.2",
- "hyper-tls",
+ "hyper-tls 0.5.0",
  "ipnet",
  "js-sys",
  "log",
@@ -8418,12 +8660,12 @@ dependencies = [
  "percent-encoding",
  "pin-project-lite",
  "rustls 0.21.12",
- "rustls-pemfile",
+ "rustls-pemfile 1.0.4",
  "serde",
  "serde_json",
  "serde_urlencoded",
- "sync_wrapper",
- "system-configuration",
+ "sync_wrapper 0.1.2",
+ "system-configuration 0.5.1",
  "tokio",
  "tokio-native-tls",
  "tokio-rustls 0.24.1",
@@ -8436,6 +8678,57 @@ dependencies = [
  "winreg",
 ]
 
+[[package]]
+name = "reqwest"
+version = "0.12.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43e734407157c3c2034e0258f5e4473ddb361b1e85f95a66690d67264d7cd1da"
+dependencies = [
+ "base64 0.22.1",
+ "bytes",
+ "encoding_rs",
+ "futures-core",
+ "futures-util",
+ "h2 0.4.8",
+ "http 1.2.0",
+ "http-body 1.0.1",
+ "http-body-util",
+ "hyper 1.6.0",
+ "hyper-rustls 0.27.5",
+ "hyper-tls 0.6.0",
+ "hyper-util",
+ "ipnet",
+ "js-sys",
+ "log",
+ "mime",
+ "native-tls",
+ "once_cell",
+ "percent-encoding",
+ "pin-project-lite",
+ "quinn",
+ "rustls 0.23.16",
+ "rustls-pemfile 2.2.0",
+ "rustls-pki-types",
+ "serde",
+ "serde_json",
+ "serde_urlencoded",
+ "sync_wrapper 1.0.2",
+ "system-configuration 0.6.1",
+ "tokio",
+ "tokio-native-tls",
+ "tokio-rustls 0.26.1",
+ "tokio-util 0.7.12",
+ "tower 0.5.2",
+ "tower-service",
+ "url",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "wasm-streams",
+ "web-sys",
+ "webpki-roots 0.26.8",
+ "windows-registry",
+]
+
 [[package]]
 name = "resolv-conf"
 version = "0.7.0"
@@ -8714,7 +9007,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a9aace74cb666635c918e9c12bc0d348266037aa8eb599b5cba565709a8dff00"
 dependencies = [
  "openssl-probe",
- "rustls-pemfile",
+ "rustls-pemfile 1.0.4",
  "schannel",
  "security-framework",
 ]
@@ -8728,6 +9021,15 @@ dependencies = [
  "base64 0.21.7",
 ]
 
+[[package]]
+name = "rustls-pemfile"
+version = "2.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dce314e5fee3f39953d46bb63bb8a46d40c2f8fb7cc5a3b6cab2bde9721d6e50"
+dependencies = [
+ "rustls-pki-types",
+]
+
 [[package]]
 name = "rustls-pki-types"
 version = "1.10.0"
@@ -9681,7 +9983,7 @@ dependencies = [
  "fs2",
  "hex",
  "once_cell",
- "reqwest",
+ "reqwest 0.11.27",
  "semver",
  "serde",
  "serde_json",
@@ -9719,6 +10021,15 @@ version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2047c6ded9c721764247e62cd3b03c09ffc529b2ba5b10ec482ae507a4a70160"
 
+[[package]]
+name = "sync_wrapper"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0bf256ce5efdfa370213c1dabab5935a12e49f2c58d15e9eac2870d3b4f27263"
+dependencies = [
+ "futures-core",
+]
+
 [[package]]
 name = "synstructure"
 version = "0.12.6"
@@ -9750,7 +10061,18 @@ checksum = "ba3a3adc5c275d719af8cb4272ea1c4a6d668a777f37e115f6d11ddbc1c8e0e7"
 dependencies = [
  "bitflags 1.3.2",
  "core-foundation",
- "system-configuration-sys",
+ "system-configuration-sys 0.5.0",
+]
+
+[[package]]
+name = "system-configuration"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3c879d448e9d986b661742763247d3693ed13609438cf3d006f51f5368a5ba6b"
+dependencies = [
+ "bitflags 2.6.0",
+ "core-foundation",
+ "system-configuration-sys 0.6.0",
 ]
 
 [[package]]
@@ -9763,6 +10085,16 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "system-configuration-sys"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e1d1b10ced5ca923a1fcb8d03e96b8d3268065d724548c0211415ff6ac6bac4"
+dependencies = [
+ "core-foundation-sys",
+ "libc",
+]
+
 [[package]]
 name = "tap"
 version = "1.0.1"
@@ -9930,8 +10262,8 @@ dependencies = [
  "flex-error",
  "futures",
  "getrandom",
- "http",
- "hyper",
+ "http 0.2.12",
+ "hyper 0.14.31",
  "hyper-proxy",
  "hyper-rustls 0.22.1",
  "peg",
@@ -10190,6 +10522,16 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "tokio-rustls"
+version = "0.26.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5f6d0975eaace0cf0fcadee4e4aaa5da15b5c079146f2cffb67c113be122bf37"
+dependencies = [
+ "rustls 0.23.16",
+ "tokio",
+]
+
 [[package]]
 name = "tokio-stream"
 version = "0.1.16"
@@ -10347,6 +10689,21 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "tower"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d039ad9159c98b70ecfd540b2573b97f7f52c3e8d9f8ad57a24b916a536975f9"
+dependencies = [
+ "futures-core",
+ "futures-util",
+ "pin-project-lite",
+ "sync_wrapper 1.0.2",
+ "tokio",
+ "tower-layer",
+ "tower-service",
+]
+
 [[package]]
 name = "tower-abci"
 version = "0.7.0"
@@ -10362,7 +10719,7 @@ dependencies = [
  "tokio",
  "tokio-stream",
  "tokio-util 0.6.10",
- "tower",
+ "tower 0.4.13",
  "tracing",
 ]
 
@@ -10376,8 +10733,8 @@ dependencies = [
  "bytes",
  "futures-core",
  "futures-util",
- "http",
- "http-body",
+ "http 0.2.12",
+ "http-body 0.4.6",
  "http-range-header",
  "pin-project-lite",
  "tower-layer",
@@ -10417,7 +10774,7 @@ dependencies = [
  "crossbeam-channel",
  "thiserror 1.0.69",
  "time",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
 ]
 
 [[package]]
@@ -10441,6 +10798,16 @@ dependencies = [
  "valuable",
 ]
 
+[[package]]
+name = "tracing-error"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b4d7c0b83d4a500748fa5879461652b361edf5c9d51ede2a2ac03875ca185e24"
+dependencies = [
+ "tracing",
+ "tracing-subscriber 0.2.25",
+]
+
 [[package]]
 name = "tracing-error"
 version = "0.2.1"
@@ -10448,7 +10815,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8b1581020d7a273442f5b45074a6a57d5757ad0a47dac0e9f0bd57b81936f3db"
 dependencies = [
  "tracing",
- "tracing-subscriber",
+ "tracing-subscriber 0.3.18",
 ]
 
 [[package]]
@@ -10482,6 +10849,17 @@ dependencies = [
  "tracing-core",
 ]
 
+[[package]]
+name = "tracing-subscriber"
+version = "0.2.25"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0e0d2eaa99c3c2e41547cfa109e910a68ea03823cccad4a0525dcbc9b01e8c71"
+dependencies = [
+ "sharded-slab",
+ "thread_local",
+ "tracing-core",
+]
+
 [[package]]
 name = "tracing-subscriber"
 version = "0.3.18"
@@ -10544,7 +10922,7 @@ dependencies = [
  "base64 0.13.1",
  "byteorder",
  "bytes",
- "http",
+ "http 0.2.12",
  "httparse",
  "log",
  "native-tls",
@@ -10566,7 +10944,7 @@ dependencies = [
  "byteorder",
  "bytes",
  "data-encoding",
- "http",
+ "http 0.2.12",
  "httparse",
  "log",
  "rand",
@@ -10908,6 +11286,19 @@ dependencies = [
  "leb128",
 ]
 
+[[package]]
+name = "wasm-streams"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "15053d8d85c7eccdbefef60f06769760a563c7f0a9d6902a13d35c7800b0ad65"
+dependencies = [
+ "futures-util",
+ "js-sys",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+]
+
 [[package]]
 name = "wasmparser"
 version = "0.95.0"
@@ -11193,6 +11584,15 @@ version = "0.25.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5f20c57d8d7db6d3b86154206ae5d8fba62dd39573114de97c2cb0578251f8e1"
 
+[[package]]
+name = "webpki-roots"
+version = "0.26.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2210b291f7ea53617fbafcc4939f10914214ec15aace5ba62293a668f322c5c9"
+dependencies = [
+ "rustls-pki-types",
+]
+
 [[package]]
 name = "which"
 version = "4.4.2"
@@ -11270,6 +11670,36 @@ dependencies = [
  "windows-targets 0.52.6",
 ]
 
+[[package]]
+name = "windows-registry"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e400001bb720a623c1c69032f8e3e4cf09984deec740f007dd2b03ec864804b0"
+dependencies = [
+ "windows-result",
+ "windows-strings",
+ "windows-targets 0.52.6",
+]
+
+[[package]]
+name = "windows-result"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d1043d8214f791817bab27572aaa8af63732e11bf84aa21a45a78d6c317ae0e"
+dependencies = [
+ "windows-targets 0.52.6",
+]
+
+[[package]]
+name = "windows-strings"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4cd9b125c486025df0eabcb585e62173c6c9eddcec5d117d3b6e8c30e2ee4d10"
+dependencies = [
+ "windows-result",
+ "windows-targets 0.52.6",
+]
+
 [[package]]
 name = "windows-sys"
 version = "0.48.0"
diff --git a/Cargo.toml b/Cargo.toml
index 1a4ee2498..9f08d4949 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -36,6 +36,8 @@ members = [
   "fendermint/tracing",
   "fendermint/vm/*",
   "fendermint/actors",
+  "fendermint/actors-custom-car",
+  "fendermint/actors-builtin-car",
   "fendermint/actors/api",
   "fendermint/actors/chainmetadata",
   "fendermint/actors/activity-tracker",
@@ -69,6 +71,7 @@ blake2b_simd = "1.0"
 bloom = "0.3"
 bytes = "1.4"
 clap = { version = "4.1", features = ["derive", "env", "string"] }
+color-eyre = "0.5.11"
 byteorder = "1.5.0"
 config = "0.13"
 dirs = "5.0"
diff --git a/fendermint/actors-builtin-car/Cargo.toml b/fendermint/actors-builtin-car/Cargo.toml
new file mode 100644
index 000000000..823cdab7d
--- /dev/null
+++ b/fendermint/actors-builtin-car/Cargo.toml
@@ -0,0 +1,17 @@
+[package]
+name = "actors-builtin-car"
+version = "0.1.0"
+authors.workspace = true
+edition.workspace = true
+license.workspace = true
+license-file.workspace = true
+
+[build-dependencies]
+reqwest = { version = "0.12", features = ["rustls-tls", "stream"] }
+tokio = { version = "1", features = ["full"] }
+fs-err = { workspace = true }
+sha2 = { workspace = true }
+tempfile = { workspace = true }
+color-eyre = { workspace = true }
+futures-util = { workspace = true }
+bytes = { workspace = true }
diff --git a/fendermint/actors-builtin-car/build.rs b/fendermint/actors-builtin-car/build.rs
new file mode 100644
index 000000000..6d539e013
--- /dev/null
+++ b/fendermint/actors-builtin-car/build.rs
@@ -0,0 +1,155 @@
+// Copyright 2022-2024 Protocol Labs
+// SPDX-License-Identifier: Apache-2.0, MIT
+//! Download filecoin's builtin actors car file
+
+use bytes::buf::Buf;
+use color_eyre::eyre::{self, bail, Result, WrapErr};
+use fs_err as fs;
+use futures_util::stream::StreamExt;
+use sha2::Digest;
+use std::io::{Read, Write};
+use std::path::Path;
+use tempfile::NamedTempFile;
+
+const BUILTIN_ACTORS_TAG: &str = "v15.0.0";
+
+const FORCE_RERUN: &str = "IPC_BUILTIN_ACTORS_FORCE_FETCH";
+
+const VERSION_OVERRIDE: &str = "IPC_BUILTIN_ACTORS_VERSION_OVERRIDE";
+
+/// Handle `Interrupt` errors, call a closure for each read kb piece
+fn read_file_piecewise<R: Read, F: FnMut(&[u8]) -> Result<()>>(
+    mut reader: R,
+    mut f: F,
+) -> Result<()> {
+    let mut buf = [0u8; 1024];
+    loop {
+        match reader.read(&mut buf[..]) {
+            Ok(0) => {
+                return Ok(());
+            }
+            Ok(n) => {
+                f(&buf[..n])?;
+            }
+            Err(e) => match e.kind() {
+                std::io::ErrorKind::Interrupted => continue,
+                _ => return Err(e.into()),
+            },
+        }
+    }
+}
+
+/// Calculate the digest of a file
+fn file_digest(reader: impl Read) -> Result<Checksum> {
+    let mut sha = sha2::Sha256::default();
+    read_file_piecewise(reader, |bytes| {
+        sha.write_all(bytes)?;
+        Ok(())
+    })?;
+    let digest = sha.finalize();
+    Checksum::try_from(digest.as_slice())
+}
+
+/// Convert a slice to an array
+///
+/// The slice must have the exact length of the array size `N`.
+fn slice_to_array<const N: usize>(bytes: &[u8]) -> Result<[u8; N]> {
+    if bytes.len() != N {
+        bail!("Length mismatch, execpted {}, but got {}", N, bytes.len());
+    }
+    let mut buf = [0u8; N];
+    buf.copy_from_slice(&bytes[..N]);
+    Ok(buf)
+}
+
+/// Digest wrapping type
+#[derive(Debug, PartialEq, Eq, Hash)]
+struct Checksum([u8; 32]);
+
+impl TryFrom<&[u8]> for Checksum {
+    type Error = eyre::Error;
+    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
+        Ok(Checksum(slice_to_array::<32>(value)?))
+    }
+}
+
+fn tempfile(out_dir: &Path) -> Result<NamedTempFile> {
+    let t = NamedTempFile::new_in(out_dir)?;
+    Ok(t)
+}
+
+/// Download the file piecewise to a temporary file and calculate the digest
+async fn download_builtin_actors_bundle(
+    tag: impl AsRef<str>,
+    out_dir: &Path,
+) -> Result<(NamedTempFile, Checksum)> {
+    let tag = tag.as_ref();
+    let mut tmp = tempfile(out_dir)?;
+
+    let url = format!("https://github.com/filecoin-project/builtin-actors/releases/download/{tag}/builtin-actors-mainnet.car");
+    let url = reqwest::Url::parse(&url)?;
+
+    let response = reqwest::get(url).await?;
+    let mut stream = response.bytes_stream();
+    // concurrently compute the sha2 & write to temp file
+    let mut sha = sha2::Sha256::default();
+    while let Some(piece) = stream.next().await {
+        let piece = piece?;
+        let piece = piece.slice(..);
+        let mut reader = piece.clone().reader();
+        std::io::copy(&mut reader, &mut sha)?;
+
+        let mut reader = piece.clone().reader();
+        std::io::copy(&mut reader, &mut tmp.as_file_mut())?;
+    }
+    let digest = sha.finalize();
+    let digest = Checksum::try_from(digest.as_slice())?;
+    Ok((tmp, digest))
+}
+
+#[tokio::main]
+async fn main() -> color_eyre::eyre::Result<()> {
+    let out_dir = std::env::var("OUT_DIR").wrap_err("Missing OUT_DIR env")?;
+    let out_dir = std::path::PathBuf::from(out_dir);
+
+    let builtin_car_path = out_dir.join("builtin_actors.car");
+
+    println!("cargo:rerun_if_changed=build.rs");
+    println!("cargo:rerun_if_env_changed={}", FORCE_RERUN);
+    println!("cargo:rerun_if_env_changed={}", VERSION_OVERRIDE);
+
+    println!("cargo:rerun_if_changed={}", builtin_car_path.display());
+
+    let tag = std::env::var(VERSION_OVERRIDE).unwrap_or_else(|_e| BUILTIN_ACTORS_TAG.to_owned());
+
+    let (tmp, tmp_digest) = download_builtin_actors_bundle(tag, &out_dir).await?;
+
+    match fs::File::open(&builtin_car_path) {
+        Ok(f) => {
+            // compare digests, if mismatch, replace existing with the downloaded file
+            let actual = file_digest(f)?;
+            if tmp_digest != actual {
+                fs::remove_file(&builtin_car_path)?;
+                fs::rename(tmp.path(), &builtin_car_path)?;
+            } else {
+                println!("Nothing to do, identical file is already present");
+            }
+        }
+        Err(e) => {
+            if let std::io::ErrorKind::NotFound = e.kind() {
+                // the file is not found, so a simple rename is good enough
+                fs::rename(tmp.path(), &builtin_car_path)?;
+            } else {
+                // other errors always must lead to an error
+                bail!(e)
+            }
+        }
+    }
+
+    println!(
+        "Builtin actors file is ready for inclusion: {}",
+        builtin_car_path.display()
+    );
+
+    Ok(())
+}
diff --git a/fendermint/actors-builtin-car/src/lib.rs b/fendermint/actors-builtin-car/src/lib.rs
new file mode 100644
index 000000000..3c5cfb92a
--- /dev/null
+++ b/fendermint/actors-builtin-car/src/lib.rs
@@ -0,0 +1,5 @@
+// Copyright 2022-2024 Protocol Labs
+// SPDX-License-Identifier: Apache-2.0, MIT
+/// Included builtin actors bundle
+pub const CAR: &[u8] =
+    include_bytes!(concat!(env!("OUT_DIR"), "/", "builtin_actors.car"));
diff --git a/fendermint/actors-custom-car/Cargo.toml b/fendermint/actors-custom-car/Cargo.toml
new file mode 100644
index 000000000..f6cb240cb
--- /dev/null
+++ b/fendermint/actors-custom-car/Cargo.toml
@@ -0,0 +1,28 @@
+[package]
+name = "fendermint_actors"
+version = "0.1.0"
+authors.workspace = true
+edition.workspace = true
+license.workspace = true
+
+[dependencies]
+cid = { workspace = true }
+anyhow = { workspace = true }
+fvm_ipld_blockstore = { workspace = true }
+fvm_ipld_encoding = { workspace = true }
+# only included for their static names (!)
+fendermint_actor_activity_tracker = { path = "../actors/activity-tracker" }
+fendermint_actor_chainmetadata = { path = "../actors/chainmetadata" }
+fendermint_actor_gas_market_eip1559 = { path = "../actors/gas_market/eip1559" }
+fendermint_actor_eam = { path = "../actors/eam" }
+
+[build-dependencies]
+color-eyre = { workspace = true }
+fs-err = { workspace = true }
+fil_actors_runtime = { workspace = true, features = ["test_utils"] }
+fil_actor_bundler = "6.1.0"
+num-traits = { workspace = true }
+toml = "0.8.19"
+cargo_metadata = "0.19"
+ignore = "0.4"
+tracing = "0.1"
diff --git a/fendermint/actors-custom-car/README.md b/fendermint/actors-custom-car/README.md
new file mode 100644
index 000000000..84afef2fc
--- /dev/null
+++ b/fendermint/actors-custom-car/README.md
@@ -0,0 +1,3 @@
+# Actors Car
+
+The `.car` file, containing all custom / extra actors.
diff --git a/fendermint/actors-custom-car/build.rs b/fendermint/actors-custom-car/build.rs
new file mode 100644
index 000000000..eb125fb3c
--- /dev/null
+++ b/fendermint/actors-custom-car/build.rs
@@ -0,0 +1,366 @@
+// Copyright 2022-2024 Protocol Labs
+// Copyright Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0, MIT
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use cargo_metadata::{DependencyKind, MetadataCommand};
+use color_eyre::eyre::{bail, eyre, OptionExt, Result};
+use fil_actor_bundler::Bundler;
+use fs_err as fs;
+use std::collections::HashSet;
+use std::io::{BufRead, BufReader};
+use std::ops::Deref;
+use std::path::{Path, PathBuf};
+use std::process::{Command, Stdio};
+use std::thread;
+use toml::Value;
+use tracing::info;
+
+fn parse_dependencies_of_umbrella_crate(manifest_path: &Path) -> Result<Vec<(String, PathBuf)>> {
+    let manifest = dbg!(fs::read_to_string(manifest_path))?;
+    let document = dbg!(manifest.parse::<Value>()?);
+
+    let dependencies = document
+        .get("target")
+        .ok_or_eyre("could not find target table")?
+        .get(r#"cfg(target_arch = "wasm32")"#)
+        .ok_or_eyre("could not find target_arch table")?
+        .get("dependencies")
+        .ok_or_eyre("could not find dependencies table")?
+        .as_table()
+        .ok_or_eyre("could not find dependencies")?;
+
+    let mut ret = Vec::with_capacity(dependencies.len());
+    for (name, details) in dependencies.iter() {
+        let Some(path) = details.get("path").and_then(Value::as_str) else {
+            continue;
+        };
+        ret.push((name.clone(), std::path::PathBuf::from(path)));
+    }
+
+    Ok(ret)
+}
+
+pub fn rerun_if_changed(path: &Path) {
+    println!("cargo:rerun-if-changed={}", path.display());
+}
+
+/// Custom wrapper for a [`cargo_metadata::Package`] to store it in
+/// a `HashSet`.
+#[derive(Debug)]
+struct DeduplicatePackage<'a> {
+    package: &'a cargo_metadata::Package,
+    identifier: String,
+}
+impl<'a> From<&'a cargo_metadata::Package> for DeduplicatePackage<'a> {
+    fn from(package: &'a cargo_metadata::Package) -> Self {
+        Self {
+            package,
+            identifier: format!("{}{}{:?}", package.name, package.version, package.source),
+        }
+    }
+}
+
+impl<'a> std::hash::Hash for DeduplicatePackage<'a> {
+    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
+        self.identifier.hash(state);
+    }
+}
+
+impl<'a> PartialEq for DeduplicatePackage<'a> {
+    fn eq(&self, other: &Self) -> bool {
+        self.identifier == other.identifier
+    }
+}
+
+impl<'a> Eq for DeduplicatePackage<'a> {}
+
+impl<'a> Deref for DeduplicatePackage<'a> {
+    type Target = cargo_metadata::Package;
+
+    fn deref(&self) -> &Self::Target {
+        self.package
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+struct Actor {
+    package_name: String,
+    crate_path: PathBuf,
+    wasm_blob_path: PathBuf,
+}
+
+/// Bundle all indidivual wasm blobs together
+fn bundle_wasm_blobs_into_car(actor_wasm_blobs: &[Actor], dst: &Path) -> Result<PathBuf> {
+    let mut bundler = Bundler::new(dst);
+    for (
+        Actor {
+            package_name: pkg,
+            wasm_blob_path: path,
+            ..
+        },
+        id,
+    ) in actor_wasm_blobs.iter().zip(1u32..)
+    {
+        // This actor version doesn't force synthetic CIDs; it uses genuine
+        // content-addressed CIDs.
+        let forced_cid = None;
+
+        let actor_name = pkg
+            .strip_prefix("fendermint_actor_")
+            .ok_or_eyre(format!(
+                "expected fendermint_actor_ prefix in actor package name; got: {pkg}"
+            ))?
+            .to_owned();
+
+        let cid = bundler
+            .add_from_file(id, actor_name, forced_cid, path)
+            .map_err(|err| {
+                eyre!(
+                    "failed to add file {:?} to bundle for actor {}: {}",
+                    path,
+                    id,
+                    err
+                )
+            })?;
+        info!("added {} ({}) to bundle with CID {}", pkg, id, cid);
+    }
+
+    bundler
+        .finish()
+        .map_err(|e| eyre!("Failed to finish bundle builder: {e}"))?;
+
+    Ok(dst.to_path_buf())
+}
+
+fn create_metadata_command(path: impl Into<PathBuf>) -> MetadataCommand {
+    let mut metadata_command = MetadataCommand::new();
+    metadata_command.manifest_path(path);
+    // metadata_command.other_options(vec!["--offline".to_owned()]);
+    metadata_command
+}
+
+/// Find the `Cargo.lock` relative to the `OUT_DIR` environment variable.
+///
+/// If the `Cargo.lock` cannot be found, we emit a warning and return `None`.
+fn find_cargo_lock(out_dir: &Path) -> Option<PathBuf> {
+    fn find_impl(mut path: PathBuf) -> Option<PathBuf> {
+        loop {
+            if path.join("Cargo.lock").exists() {
+                return Some(path.join("Cargo.lock"));
+            }
+
+            if !path.pop() {
+                return None;
+            }
+        }
+    }
+
+    if let Some(path) = find_impl(out_dir.to_path_buf()) {
+        return Some(path);
+    }
+
+    None
+}
+
+/// Track files and paths related to the given package to rerun `build.rs` on any relevant change.
+fn package_rerun_if_changed(package: &DeduplicatePackage) {
+    let mut manifest_path = package.manifest_path.clone();
+    if manifest_path.ends_with("Cargo.toml") {
+        manifest_path.pop();
+    }
+
+    ignore::Walk::new(&manifest_path)
+        .filter(|p| {
+            // Ignore this entry if it is a directory that contains a `Cargo.toml` that is not the
+            // `Cargo.toml` related to the current package. This is done to ignore sub-crates of a
+            // crate. If such a sub-crate is a dependency, it will be processed independently
+            // anyway.
+            let Ok(p) = p else { return false };
+            let p = p.path();
+            p == manifest_path || !p.is_dir() || !p.join("Cargo.toml").exists()
+        })
+        .filter_map(|p| p.ok().map(|p| p.into_path()))
+        .filter(|p| {
+            p.extension()
+                .map(|e| e == "rs" || e == "toml")
+                .unwrap_or_default()
+        })
+        .for_each(|ref x| rerun_if_changed(x));
+}
+
+fn build_all_wasm_blobs(
+    actors: &[Actor],
+    manifest_path: &Path,
+    cargo: &Path,
+    out_dir: &Path,
+) -> Result<Vec<Actor>> {
+    let package_args = actors
+        .iter()
+        .map(|actor| format!("-p={}", actor.package_name));
+
+    // Cargo build command for all test_actors at once.
+    let mut cmd = Command::new(cargo);
+    cmd.arg("build")
+        .args(package_args)
+        .arg("--target=wasm32-unknown-unknown")
+        .arg("--profile=wasm")
+        .arg("--features=fil-actor")
+        .arg(format!("--manifest-path={}", manifest_path.display()))
+        .stdout(Stdio::piped())
+        .stderr(Stdio::piped())
+        // We are supposed to only generate artifacts under OUT_DIR,
+        // so set OUT_DIR as the target directory for this build.
+        .env("CARGO_TARGET_DIR", out_dir)
+        // As we are being called inside a build-script, this env variable is set. However, we set
+        // our own `RUSTFLAGS` and thus, we need to remove this. Otherwise cargo favors this
+        // env variable.
+        .env_remove("CARGO_ENCODED_RUSTFLAGS");
+
+    // Launch the command.
+    let mut child = cmd.spawn()?;
+
+    // Pipe the output as cargo warnings. Unfortunately this is the only way to
+    // get cargo build to print the output.
+    let stdout = child.stdout.take().expect("no stdout");
+    let stderr = child.stderr.take().expect("no stderr");
+    let j1 = thread::spawn(move || {
+        for line in BufReader::new(stderr).lines() {
+            println!("cargo:warning={:?}", line.unwrap());
+        }
+    });
+    let j2 = thread::spawn(move || {
+        for line in BufReader::new(stdout).lines() {
+            println!("cargo:warning={:?}", line.unwrap());
+        }
+    });
+
+    let _ = j1.join();
+    let _ = j2.join();
+
+    let exit_status = child.wait()?;
+    if !exit_status.success() {
+        bail!("actor build faile");
+    }
+    Ok(actors.to_vec())
+}
+
+/// Use the `Cargo.lock` file to find the workspace manifest and extract dependency information
+fn print_cargo_rerun_if_dependency_instructions(
+    cargo_manifest: &Path,
+    out_dir: &Path,
+) -> Result<()> {
+    // Rerun `build.rs` if the `Cargo.lock` changes
+    let cargo_lock = find_cargo_lock(out_dir).ok_or_eyre("Couldn't find Cargo.lock")?;
+    rerun_if_changed(&cargo_lock);
+
+    let workspace = cargo_lock.parent().unwrap();
+
+    let metadata = create_metadata_command(workspace.join("Cargo.toml")).exec()?;
+
+    let package = metadata
+        .packages
+        .iter()
+        .find(|p| p.manifest_path == cargo_manifest)
+        .ok_or_eyre("Detected a circular dependency. The crate depends on itself..")?;
+
+    // Start with the dependencies of the crate we want to compile for wasm.
+    let mut dependencies = Vec::from_iter(package.dependencies.iter());
+
+    // Collect all packages by follow the dependencies of all packages we find.
+    let mut packages = HashSet::new();
+    packages.insert(DeduplicatePackage::from(package));
+
+    while let Some(dependency) = dependencies.pop() {
+        // Ignore all dev dependencies
+        if dependency.kind == DependencyKind::Development {
+            continue;
+        }
+
+        let path_or_git_dep = dependency
+            .source
+            .as_ref()
+            .map(|s| s.starts_with("git+"))
+            .unwrap_or(true);
+
+        let maybe_package = metadata
+            .packages
+            .iter()
+            .filter(|p| !p.manifest_path.starts_with(workspace))
+            .find(|p| {
+                // Check that the name matches and that the version matches or this is
+                // a git or path dep. A git or path dependency can only occur once, so we don't
+                // need to check the version.
+                (path_or_git_dep || dependency.req.matches(&p.version)) && dependency.name == p.name
+            });
+
+        if let Some(package) = maybe_package {
+            if packages.insert(DeduplicatePackage::from(package)) {
+                dependencies.extend(package.dependencies.iter());
+            }
+        }
+    }
+
+    // Make sure that if any file/folder of a dependency change, we need to rerun the `build.rs`
+    packages.iter().for_each(package_rerun_if_changed);
+
+    Ok(())
+}
+
+fn main() -> Result<()> {
+    // Cargo executable location.
+    let cargo = std::env::var_os("CARGO").ok_or_eyre("no CARGO env var")?;
+    let cargo = Path::new(&cargo);
+
+    // Rust provided out dir, used as intermediate place to store a) wasm target dir b) their outputs
+    // the final `.car` file will sit under `dst`.
+    let out_dir = std::env::var_os("OUT_DIR")
+        .as_ref()
+        .map(Path::new)
+        .map(|p| p.join("bundle"))
+        .ok_or_eyre("Must have OUT_DIR defined, this is only ever run from build.rs")?;
+
+    let manifest_path_dir =
+        std::env::var_os("CARGO_MANIFEST_DIR").ok_or_eyre("CARGO_MANIFEST_DIR unset")?;
+    let manifest_path_dir = Path::new(&manifest_path_dir);
+    let actors_manifest_path = manifest_path_dir
+        .parent()
+        .unwrap()
+        .join("actors")
+        .join("Cargo.toml");
+
+    let wasm_blob_dir = out_dir.join("wasm32-unknown-unknown").join("wasm");
+
+    let actors = parse_dependencies_of_umbrella_crate(&actors_manifest_path)?;
+    let actors = Vec::from_iter(actors.iter().map(|(name, crate_path)| Actor {
+        package_name: name.as_str().to_owned(),
+        wasm_blob_path: wasm_blob_dir.join(name.as_str()).with_extension("wasm"),
+        crate_path: crate_path.clone(),
+    }));
+
+    print_cargo_rerun_if_dependency_instructions(&actors_manifest_path, &out_dir)?;
+
+    build_all_wasm_blobs(&actors, &actors_manifest_path, cargo, &out_dir)?;
+
+    let bundle_car_dest_dir = actors_manifest_path.parent().unwrap().join("output");
+
+    fs_err::create_dir_all(&bundle_car_dest_dir)?;
+    let bundle_car_path = bundle_car_dest_dir.join("custom_actors_bundle.car");
+
+    rerun_if_changed(&bundle_car_path);
+
+    bundle_wasm_blobs_into_car(&actors, &bundle_car_path)?;
+
+    Ok(())
+}
diff --git a/fendermint/actors-custom-car/src/lib.rs b/fendermint/actors-custom-car/src/lib.rs
new file mode 100644
index 000000000..25e919d67
--- /dev/null
+++ b/fendermint/actors-custom-car/src/lib.rs
@@ -0,0 +1,12 @@
+// Copyright 2022-2024 Protocol Labs
+// SPDX-License-Identifier: Apache-2.0, MIT
+mod manifest;
+
+pub use manifest::Manifest;
+
+/// Included bytes for custom actor bundle, ~1.3M in size
+pub const CUSTOM_ACTORS: &[u8] = include_bytes!(concat!(
+    env!("CARGO_MANIFEST_DIR"),
+    "/../actors/output/",
+    "custom_actors_bundle.car"
+));
diff --git a/fendermint/actors/src/manifest.rs b/fendermint/actors-custom-car/src/manifest.rs
similarity index 100%
rename from fendermint/actors/src/manifest.rs
rename to fendermint/actors-custom-car/src/manifest.rs
diff --git a/fendermint/actors/Cargo.toml b/fendermint/actors/Cargo.toml
index d50176cd0..089f43132 100644
--- a/fendermint/actors/Cargo.toml
+++ b/fendermint/actors/Cargo.toml
@@ -1,30 +1,18 @@
 [package]
-name = "fendermint_actors"
+name = "actors-umbrella"
 version = "0.1.0"
 authors.workspace = true
 edition.workspace = true
 license.workspace = true
+description = "Depend on all individual actors to be included."
 
+# we use the list of dependencies
+# to determine which ones to include in the `.car` file
+# and filter for the `fendermint_actor_` prefix
+# the all-in-one wasmblob is NOT used, nor should it be compiled,
+# neither for the host nor target arch
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 fendermint_actor_activity_tracker = { path = "activity-tracker", features = ["fil-actor"] }
 fendermint_actor_chainmetadata = { path = "chainmetadata", features = ["fil-actor"] }
 fendermint_actor_gas_market_eip1559 = { path = "gas_market/eip1559", features = ["fil-actor"] }
 fendermint_actor_eam = { path = "eam", features = ["fil-actor"] }
-
-[dependencies]
-cid = { workspace = true }
-anyhow = { workspace = true }
-fvm_ipld_blockstore = { workspace = true }
-fvm_ipld_encoding = { workspace = true }
-fendermint_actor_chainmetadata = { path = "chainmetadata" }
-fendermint_actor_eam = { path = "eam" }
-fendermint_actor_gas_market_eip1559 = { path = "gas_market/eip1559" }
-fs-err = { workspace = true }
-
-[build-dependencies]
-anyhow = { workspace = true }
-fil_actors_runtime = { workspace = true, features = ["test_utils"] }
-fil_actor_bundler = "6.1.0"
-fs-err = { workspace = true }
-num-traits = { workspace = true }
-toml = "0.8.19"
diff --git a/fendermint/actors/build.rs b/fendermint/actors/build.rs
deleted file mode 100644
index 6f452be35..000000000
--- a/fendermint/actors/build.rs
+++ /dev/null
@@ -1,152 +0,0 @@
-// Copyright 2022-2024 Protocol Labs
-// SPDX-License-Identifier: Apache-2.0, MIT
-
-use anyhow::anyhow;
-use fil_actor_bundler::Bundler;
-use fs_err as fs;
-use std::error::Error;
-use std::io::{BufRead, BufReader};
-use std::path::Path;
-use std::process::{Command, Stdio};
-use std::thread;
-use toml::Value;
-
-fn parse_dependencies_for_wasm32() -> anyhow::Result<Vec<(String, String)>> {
-    let manifest = fs::read_to_string("Cargo.toml")?;
-    let document = manifest.parse::<Value>()?;
-
-    let dependencies = document
-        .get("target")
-        .and_then(|t| t.get(r#"cfg(target_arch = "wasm32")"#))
-        .and_then(|t| t.get("dependencies"))
-        .and_then(Value::as_table)
-        .ok_or_else(|| anyhow!("could not find wasm32 dependencies"))?;
-
-    let mut ret = Vec::with_capacity(dependencies.len());
-    for (name, details) in dependencies.iter() {
-        let path = details
-            .get("path")
-            .and_then(Value::as_str)
-            .ok_or_else(|| anyhow!("could not find path for a wasm32 dependency"))?;
-        ret.push((name.clone(), path.to_string()));
-    }
-
-    Ok(ret)
-}
-
-const FILES_TO_WATCH: &[&str] = &["Cargo.toml", "src"];
-
-fn main() -> Result<(), Box<dyn Error>> {
-    // Cargo executable location.
-    let cargo = std::env::var_os("CARGO").expect("no CARGO env var");
-
-    let out_dir = std::env::var_os("OUT_DIR")
-        .as_ref()
-        .map(Path::new)
-        .map(|p| p.join("bundle"))
-        .expect("no OUT_DIR env var");
-    println!("cargo:warning=out_dir: {:?}", &out_dir);
-
-    let manifest_path =
-        Path::new(&std::env::var_os("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR unset"))
-            .join("Cargo.toml");
-
-    let actors = parse_dependencies_for_wasm32()?;
-    let actor_files = actors
-        .iter()
-        .map(|(name, _)| name.as_str())
-        .collect::<Vec<_>>();
-
-    for file in [FILES_TO_WATCH, actor_files.as_slice()].concat() {
-        println!("cargo:rerun-if-changed={}", file);
-    }
-
-    // Cargo build command for all test_actors at once.
-    let mut cmd = Command::new(cargo);
-    cmd.arg("build")
-        .args(actors.iter().map(|(pkg, _)| "-p=".to_owned() + pkg))
-        .arg("--target=wasm32-unknown-unknown")
-        .arg("--profile=wasm")
-        .arg("--features=fil-actor")
-        .arg(format!("--manifest-path={}", manifest_path.display()))
-        .stdout(Stdio::piped())
-        .stderr(Stdio::piped())
-        // We are supposed to only generate artifacts under OUT_DIR,
-        // so set OUT_DIR as the target directory for this build.
-        .env("CARGO_TARGET_DIR", &out_dir)
-        // As we are being called inside a build-script, this env variable is set. However, we set
-        // our own `RUSTFLAGS` and thus, we need to remove this. Otherwise cargo favors this
-        // env variable.
-        .env_remove("CARGO_ENCODED_RUSTFLAGS");
-
-    // Print out the command line we're about to run.
-    println!("cargo:warning=cmd={:?}", &cmd);
-
-    // Launch the command.
-    let mut child = cmd.spawn().expect("failed to launch cargo build");
-
-    // Pipe the output as cargo warnings. Unfortunately this is the only way to
-    // get cargo build to print the output.
-    let stdout = child.stdout.take().expect("no stdout");
-    let stderr = child.stderr.take().expect("no stderr");
-    let j1 = thread::spawn(move || {
-        for line in BufReader::new(stderr).lines() {
-            println!("cargo:warning={:?}", line.unwrap());
-        }
-    });
-    let j2 = thread::spawn(move || {
-        for line in BufReader::new(stdout).lines() {
-            println!("cargo:warning={:?}", line.unwrap());
-        }
-    });
-
-    j1.join().unwrap();
-    j2.join().unwrap();
-
-    let result = child.wait().expect("failed to wait for build to finish");
-    if !result.success() {
-        return Err("actor build failed".into());
-    }
-
-    // make sure the output dir exists
-    fs::create_dir_all("output")
-        .expect("failed to create output dir for the custom_actors_bundle.car file");
-
-    let dst = Path::new("output/custom_actors_bundle.car");
-    let mut bundler = Bundler::new(dst);
-    for (pkg, id) in actors.iter().map(|(pkg, _)| pkg).zip(1u32..) {
-        let bytecode_path = Path::new(&out_dir)
-            .join("wasm32-unknown-unknown/wasm")
-            .join(format!("{}.wasm", pkg));
-
-        // This actor version doesn't force synthetic CIDs; it uses genuine
-        // content-addressed CIDs.
-        let forced_cid = None;
-
-        let actor_name = pkg
-            .to_owned()
-            .strip_prefix("fendermint_actor_")
-            .ok_or_else(|| {
-                format!("expected fendermint_actor_ prefix in actor package name; got: {pkg}")
-            })?
-            .to_owned();
-
-        let cid = bundler
-            .add_from_file(id, actor_name, forced_cid, &bytecode_path)
-            .unwrap_or_else(|err| {
-                panic!(
-                    "failed to add file {:?} to bundle for actor {}: {}",
-                    bytecode_path, id, err
-                )
-            });
-        println!(
-            "cargo:warning=added {} ({}) to bundle with CID {}",
-            pkg, id, cid
-        );
-    }
-    bundler.finish().expect("failed to finish bundle");
-
-    println!("cargo:warning=bundle={}", dst.display());
-
-    Ok(())
-}
diff --git a/fendermint/actors/src/lib.rs b/fendermint/actors/src/lib.rs
index 006333c8a..d9da900cb 100644
--- a/fendermint/actors/src/lib.rs
+++ b/fendermint/actors/src/lib.rs
@@ -1,5 +1,3 @@
 // Copyright 2022-2024 Protocol Labs
 // SPDX-License-Identifier: Apache-2.0, MIT
-mod manifest;
-
-pub use manifest::Manifest;
+//! Empty, just a placeholder to dispatch to the dependencies
diff --git a/fendermint/app/Cargo.toml b/fendermint/app/Cargo.toml
index d2a2f1bff..5fed55d15 100644
--- a/fendermint/app/Cargo.toml
+++ b/fendermint/app/Cargo.toml
@@ -66,6 +66,11 @@ fendermint_vm_resolver = { path = "../vm/resolver" }
 fendermint_vm_snapshot = { path = "../vm/snapshot" }
 fendermint_vm_topdown = { path = "../vm/topdown" }
 
+# .car file wrapped in a crate
+actors-builtin-car =  { path = "../actors-builtin-car"}
+fendermint_actors = { path = "../actors-custom-car"}
+
+
 fs-err = { workspace = true }
 fvm = { workspace = true }
 fvm_ipld_blockstore = { workspace = true }
diff --git a/fendermint/app/src/main.rs b/fendermint/app/src/main.rs
index 99ce66b53..398391251 100644
--- a/fendermint/app/src/main.rs
+++ b/fendermint/app/src/main.rs
@@ -54,7 +54,6 @@ mod tests {
     use super::fs;
     use cid::Cid;
     use fendermint_rocksdb::{RocksDb, RocksDbConfig};
-    use fendermint_vm_interpreter::fvm::bundle::bundle_path;
     use fvm::machine::Manifest;
     use fvm_ipld_car::load_car_unchecked;
     use fvm_ipld_encoding::CborStore;
@@ -67,9 +66,7 @@ mod tests {
         // Not loading the actors from the library any more. It would be possible, as long as dependencies are aligned.
         // let bundle_car = actors_v10::BUNDLE_CAR;
 
-        let bundle_path = bundle_path();
-        let bundle_car = fs::read(&bundle_path)
-            .unwrap_or_else(|_| panic!("failed to load bundle CAR from {bundle_path:?}"));
+        let bundle_car = actors_builtin_car::CAR;
 
         let dir = tempfile::Builder::new()
             .tempdir()
@@ -81,7 +78,7 @@ mod tests {
         };
         let db = open_db();
 
-        let cids = load_car_unchecked(&db, bundle_car.as_slice())
+        let cids = load_car_unchecked(&db, bundle_car)
             .await
             .expect("error loading bundle CAR");
 
diff --git a/fendermint/vm/interpreter/Cargo.toml b/fendermint/vm/interpreter/Cargo.toml
index 1b1aca7ad..9fba35e81 100644
--- a/fendermint/vm/interpreter/Cargo.toml
+++ b/fendermint/vm/interpreter/Cargo.toml
@@ -22,7 +22,7 @@ fendermint_crypto = { path = "../../crypto" }
 fendermint_eth_hardhat = { path = "../../eth/hardhat" }
 fendermint_rpc = { path = "../../rpc" }
 fendermint_tracing = { path = "../../tracing" }
-fendermint_actors = { path = "../../actors" }
+fendermint_actors = { path = "../../actors-custom-car" }
 fendermint_actor_chainmetadata = { path = "../../actors/chainmetadata" }
 fendermint_actor_activity_tracker = { path = "../../actors/activity-tracker" }
 fendermint_actor_gas_market_eip1559 = { path = "../../actors/gas_market/eip1559" }