diff --git a/ext/fs/30_fs.js b/ext/fs/30_fs.js
index f7c07f26a7..a149f653d0 100644
--- a/ext/fs/30_fs.js
+++ b/ext/fs/30_fs.js
@@ -244,7 +244,7 @@ function createByteStruct(types) {
   // types can be "date", "bool" or "u64".
   let offset = 0;
   let str =
-    'const unix = Deno.build.os === "darwin" || Deno.build.os === "linux"; return {';
+    'const unix = Deno.build.os === "darwin" || Deno.build.os === "linux" || Deno.build.os === "openbsd" || Deno.build.os === "freebsd"; return {';
   const typeEntries = ObjectEntries(types);
   for (let i = 0; i < typeEntries.length; ++i) {
     let { 0: name, 1: type } = typeEntries[i];
@@ -309,7 +309,8 @@ const { 0: statStruct, 1: statBuf } = createByteStruct({
 });
 
 function parseFileInfo(response) {
-  const unix = core.build.os === "darwin" || core.build.os === "linux";
+  const unix = core.build.os === "darwin" || core.build.os === "linux" ||
+    core.build.os === "freebsd" || core.build.os === "openbsd";
   return {
     isFile: response.isFile,
     isDirectory: response.isDirectory,
diff --git a/ext/fs/std_fs.rs b/ext/fs/std_fs.rs
index 9baf74a2a4..b2923abb15 100644
--- a/ext/fs/std_fs.rs
+++ b/ext/fs/std_fs.rs
@@ -66,7 +66,11 @@ impl FileSystem for RealFs {
     {
       Ok(r.bits())
     }
-    #[cfg(target_os = "macos")]
+    #[cfg(any(
+      target_os = "macos",
+      target_os = "openbsd",
+      target_os = "freebsd"
+    ))]
     {
       Ok(r.bits() as u32)
     }
diff --git a/ext/node/polyfills/_util/os.ts b/ext/node/polyfills/_util/os.ts
index a3cb396bda..ff5e2efd54 100644
--- a/ext/node/polyfills/_util/os.ts
+++ b/ext/node/polyfills/_util/os.ts
@@ -2,7 +2,7 @@
 
 const { ops } = globalThis.__bootstrap.core;
 
-export type OSType = "windows" | "linux" | "darwin" | "freebsd";
+export type OSType = "windows" | "linux" | "darwin" | "freebsd" | "openbsd";
 
 export const osType: OSType = ops.op_node_build_os();
 
diff --git a/ext/node/polyfills/internal_binding/uv.ts b/ext/node/polyfills/internal_binding/uv.ts
index e7f6b890bb..bc295fa658 100644
--- a/ext/node/polyfills/internal_binding/uv.ts
+++ b/ext/node/polyfills/internal_binding/uv.ts
@@ -395,6 +395,95 @@ const errorToCodeFreebsd: CodeMapData = codeToErrorFreebsd.map((
   [status, [code]],
 ) => [code, status]);
 
+const codeToErrorOpenBSD: ErrorMapData = [
+  [-7, ["E2BIG", "argument list too long"]],
+  [-13, ["EACCES", "permission denied"]],
+  [-48, ["EADDRINUSE", "address already in use"]],
+  [-49, ["EADDRNOTAVAIL", "address not available"]],
+  [-47, ["EAFNOSUPPORT", "address family not supported"]],
+  [-35, ["EAGAIN", "resource temporarily unavailable"]],
+  [-3000, ["EAI_ADDRFAMILY", "address family not supported"]],
+  [-3001, ["EAI_AGAIN", "temporary failure"]],
+  [-3002, ["EAI_BADFLAGS", "bad ai_flags value"]],
+  [-3013, ["EAI_BADHINTS", "invalid value for hints"]],
+  [-3003, ["EAI_CANCELED", "request canceled"]],
+  [-3004, ["EAI_FAIL", "permanent failure"]],
+  [-3005, ["EAI_FAMILY", "ai_family not supported"]],
+  [-3006, ["EAI_MEMORY", "out of memory"]],
+  [-3007, ["EAI_NODATA", "no address"]],
+  [-3008, ["EAI_NONAME", "unknown node or service"]],
+  [-3009, ["EAI_OVERFLOW", "argument buffer overflow"]],
+  [-3014, ["EAI_PROTOCOL", "resolved protocol is unknown"]],
+  [-3010, ["EAI_SERVICE", "service not available for socket type"]],
+  [-3011, ["EAI_SOCKTYPE", "socket type not supported"]],
+  [-37, ["EALREADY", "connection already in progress"]],
+  [-9, ["EBADF", "bad file descriptor"]],
+  [-16, ["EBUSY", "resource busy or locked"]],
+  [-88, ["ECANCELED", "operation canceled"]],
+  [-4080, ["ECHARSET", "invalid Unicode character"]],
+  [-53, ["ECONNABORTED", "software caused connection abort"]],
+  [-61, ["ECONNREFUSED", "connection refused"]],
+  [-54, ["ECONNRESET", "connection reset by peer"]],
+  [-39, ["EDESTADDRREQ", "destination address required"]],
+  [-17, ["EEXIST", "file already exists"]],
+  [-14, ["EFAULT", "bad address in system call argument"]],
+  [-27, ["EFBIG", "file too large"]],
+  [-65, ["EHOSTUNREACH", "host is unreachable"]],
+  [-4, ["EINTR", "interrupted system call"]],
+  [-22, ["EINVAL", "invalid argument"]],
+  [-5, ["EIO", "i/o error"]],
+  [-56, ["EISCONN", "socket is already connected"]],
+  [-21, ["EISDIR", "illegal operation on a directory"]],
+  [-62, ["ELOOP", "too many symbolic links encountered"]],
+  [-24, ["EMFILE", "too many open files"]],
+  [-40, ["EMSGSIZE", "message too long"]],
+  [-63, ["ENAMETOOLONG", "name too long"]],
+  [-50, ["ENETDOWN", "network is down"]],
+  [-51, ["ENETUNREACH", "network is unreachable"]],
+  [-23, ["ENFILE", "file table overflow"]],
+  [-55, ["ENOBUFS", "no buffer space available"]],
+  [-19, ["ENODEV", "no such device"]],
+  [-2, ["ENOENT", "no such file or directory"]],
+  [-12, ["ENOMEM", "not enough memory"]],
+  [-4056, ["ENONET", "machine is not on the network"]],
+  [-42, ["ENOPROTOOPT", "protocol not available"]],
+  [-28, ["ENOSPC", "no space left on device"]],
+  [-78, ["ENOSYS", "function not implemented"]],
+  [-57, ["ENOTCONN", "socket is not connected"]],
+  [-20, ["ENOTDIR", "not a directory"]],
+  [-66, ["ENOTEMPTY", "directory not empty"]],
+  [-38, ["ENOTSOCK", "socket operation on non-socket"]],
+  [-45, ["ENOTSUP", "operation not supported on socket"]],
+  [-87, ["EOVERFLOW", "value too large for defined data type"]],
+  [-1, ["EPERM", "operation not permitted"]],
+  [-32, ["EPIPE", "broken pipe"]],
+  [-95, ["EPROTO", "protocol error"]],
+  [-43, ["EPROTONOSUPPORT", "protocol not supported"]],
+  [-41, ["EPROTOTYPE", "protocol wrong type for socket"]],
+  [-34, ["ERANGE", "result too large"]],
+  [-30, ["EROFS", "read-only file system"]],
+  [-58, ["ESHUTDOWN", "cannot send after transport endpoint shutdown"]],
+  [-29, ["ESPIPE", "invalid seek"]],
+  [-3, ["ESRCH", "no such process"]],
+  [-60, ["ETIMEDOUT", "connection timed out"]],
+  [-26, ["ETXTBSY", "text file is busy"]],
+  [-18, ["EXDEV", "cross-device link not permitted"]],
+  [-4094, ["UNKNOWN", "unknown error"]],
+  [-4095, ["EOF", "end of file"]],
+  [-6, ["ENXIO", "no such device or address"]],
+  [-31, ["EMLINK", "too many links"]],
+  [-64, ["EHOSTDOWN", "host is down"]],
+  [-4030, ["EREMOTEIO", "remote I/O error"]],
+  [-25, ["ENOTTY", "inappropriate ioctl for device"]],
+  [-79, ["EFTYPE", "inappropriate file type or format"]],
+  [-84, ["EILSEQ", "illegal byte sequence"]],
+  [-44, ["ESOCKTNOSUPPORT", "socket type not supported"]],
+];
+
+const errorToCodeOpenBSD: CodeMapData = codeToErrorOpenBSD.map((
+  [status, [code]],
+) => [code, status]);
+
 export const errorMap = new Map<number, [string, string]>(
   osType === "windows"
     ? codeToErrorWindows
@@ -404,6 +493,8 @@ export const errorMap = new Map<number, [string, string]>(
     ? codeToErrorLinux
     : osType === "freebsd"
     ? codeToErrorFreebsd
+    : osType === "openbsd"
+    ? codeToErrorOpenBSD
     : unreachable(),
 );
 
@@ -416,6 +507,8 @@ export const codeMap = new Map<string, number>(
     ? errorToCodeLinux
     : osType === "freebsd"
     ? errorToCodeFreebsd
+    : osType === "openbsd"
+    ? errorToCodeOpenBSD
     : unreachable(),
 );
 
diff --git a/ext/node/polyfills/os.ts b/ext/node/polyfills/os.ts
index 19e8fd1552..d9186159fe 100644
--- a/ext/node/polyfills/os.ts
+++ b/ext/node/polyfills/os.ts
@@ -172,6 +172,7 @@ export function homedir(): string | null {
     case "linux":
     case "darwin":
     case "freebsd":
+    case "openbsd":
       return Deno.env.get("HOME") || null;
     default:
       throw Error("unreachable");
@@ -299,6 +300,8 @@ export function type(): string {
       return "Darwin";
     case "freebsd":
       return "FreeBSD";
+    case "openbsd":
+      return "OpenBSD";
     default:
       throw Error("unreachable");
   }
diff --git a/runtime/ops/signal.rs b/runtime/ops/signal.rs
index 934192c777..ca1f2211d6 100644
--- a/runtime/ops/signal.rs
+++ b/runtime/ops/signal.rs
@@ -183,6 +183,85 @@ pub fn signal_int_to_str(s: libc::c_int) -> Result<&'static str, AnyError> {
   }
 }
 
+#[cfg(target_os = "openbsd")]
+pub fn signal_str_to_int(s: &str) -> Result<libc::c_int, AnyError> {
+  match s {
+    "SIGHUP" => Ok(1),
+    "SIGINT" => Ok(2),
+    "SIGQUIT" => Ok(3),
+    "SIGILL" => Ok(4),
+    "SIGTRAP" => Ok(5),
+    "SIGIOT" => Ok(6),
+    "SIGABRT" => Ok(6),
+    "SIGEMT" => Ok(7),
+    "SIGFPE" => Ok(8),
+    "SIGKILL" => Ok(9),
+    "SIGBUS" => Ok(10),
+    "SIGSEGV" => Ok(11),
+    "SIGSYS" => Ok(12),
+    "SIGPIPE" => Ok(13),
+    "SIGALRM" => Ok(14),
+    "SIGTERM" => Ok(15),
+    "SIGURG" => Ok(16),
+    "SIGSTOP" => Ok(17),
+    "SIGTSTP" => Ok(18),
+    "SIGCONT" => Ok(19),
+    "SIGCHLD" => Ok(20),
+    "SIGTTIN" => Ok(21),
+    "SIGTTOU" => Ok(22),
+    "SIGIO" => Ok(23),
+    "SIGXCPU" => Ok(24),
+    "SIGXFSZ" => Ok(25),
+    "SIGVTALRM" => Ok(26),
+    "SIGPROF" => Ok(27),
+    "SIGWINCH" => Ok(28),
+    "SIGINFO" => Ok(29),
+    "SIGUSR1" => Ok(30),
+    "SIGUSR2" => Ok(31),
+    "SIGTHR" => Ok(32),
+    _ => Err(type_error(format!("Invalid signal : {}", s))),
+  }
+}
+
+#[cfg(target_os = "openbsd")]
+pub fn signal_int_to_str(s: libc::c_int) -> Result<&'static str, AnyError> {
+  match s {
+    1 => Ok("SIGHUP"),
+    2 => Ok("SIGINT"),
+    3 => Ok("SIGQUIT"),
+    4 => Ok("SIGILL"),
+    5 => Ok("SIGTRAP"),
+    6 => Ok("SIGABRT"),
+    7 => Ok("SIGEMT"),
+    8 => Ok("SIGFPE"),
+    9 => Ok("SIGKILL"),
+    10 => Ok("SIGBUS"),
+    11 => Ok("SIGSEGV"),
+    12 => Ok("SIGSYS"),
+    13 => Ok("SIGPIPE"),
+    14 => Ok("SIGALRM"),
+    15 => Ok("SIGTERM"),
+    16 => Ok("SIGURG"),
+    17 => Ok("SIGSTOP"),
+    18 => Ok("SIGTSTP"),
+    19 => Ok("SIGCONT"),
+    20 => Ok("SIGCHLD"),
+    21 => Ok("SIGTTIN"),
+    22 => Ok("SIGTTOU"),
+    23 => Ok("SIGIO"),
+    24 => Ok("SIGXCPU"),
+    25 => Ok("SIGXFSZ"),
+    26 => Ok("SIGVTALRM"),
+    27 => Ok("SIGPROF"),
+    28 => Ok("SIGWINCH"),
+    29 => Ok("SIGINFO"),
+    30 => Ok("SIGUSR1"),
+    31 => Ok("SIGUSR2"),
+    32 => Ok("SIGTHR"),
+    _ => Err(type_error(format!("Invalid signal : {}", s))),
+  }
+}
+
 #[cfg(any(target_os = "android", target_os = "linux"))]
 pub fn signal_str_to_int(s: &str) -> Result<libc::c_int, AnyError> {
   match s {
diff --git a/tools/napi/generate_symbols_lists.js b/tools/napi/generate_symbols_lists.js
index 9c334c00c7..01693f4e76 100755
--- a/tools/napi/generate_symbols_lists.js
+++ b/tools/napi/generate_symbols_lists.js
@@ -7,6 +7,8 @@ import exports from "../../cli/napi/sym/symbol_exports.json" assert {
 
 const symbolExportLists = {
   linux: `{ ${exports.symbols.map((s) => `"${s}"`).join("; ")}; };`,
+  openbsd: `{ ${exports.symbols.map((s) => `"${s}"`).join("; ")}; };`,
+  freebsd: `{ ${exports.symbols.map((s) => `"${s}"`).join("; ")}; };`,
   windows: `LIBRARY\nEXPORTS\n${
     exports.symbols
       .map((symbol) => "  " + symbol)
diff --git a/tools/wpt/utils.ts b/tools/wpt/utils.ts
index 8aa27a6647..33cb9782af 100644
--- a/tools/wpt/utils.ts
+++ b/tools/wpt/utils.ts
@@ -176,6 +176,8 @@ export async function generateRunInfo(): Promise<unknown> {
     "windows": "win",
     "darwin": "mac",
     "linux": "linux",
+    "freebsd": "freebsd",
+    "openbsd": "openbsd",
   };
   const proc = await new Deno.Command("git", {
     args: ["rev-parse", "HEAD"],