diff --git a/Gemfile.lock b/Gemfile.lock
index f2cb3ed2..b9d42281 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -6,7 +6,6 @@ PATH
       activerecord (>= 6.1.0)
       concurrent-ruby (>= 1.3.1)
       fugit (>= 1.11.0)
-      get_process_mem (>= 1.0.0)
       railties (>= 6.1.0)
       thor (>= 1.0.0)
 
@@ -194,9 +193,6 @@ GEM
       et-orbi (~> 1, >= 1.2.11)
       raabro (~> 1.4)
     gem-release (2.2.2)
-    get_process_mem (1.0.0)
-      bigdecimal (>= 2.0)
-      ffi (~> 1.0)
     github_changelog_generator (1.16.4)
       activesupport
       async (>= 1.25.0)
diff --git a/app/models/good_job/process.rb b/app/models/good_job/process.rb
index 315e3cfa..ac94d14b 100644
--- a/app/models/good_job/process.rb
+++ b/app/models/good_job/process.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require 'socket'
-require 'get_process_mem'
 
 module GoodJob # :nodoc:
   # Active Record model that represents a GoodJob capsule/process (either async or CLI).
@@ -13,6 +12,22 @@ class Process < BaseRecord
     STALE_INTERVAL = 30.seconds
     # Interval until the process record is treated as expired
     EXPIRED_INTERVAL = 5.minutes
+    PROCESS_MEMORY = case RUBY_PLATFORM
+                     when /linux/
+                       ->(pid) {
+                         File.readlines("/proc/#{pid}/status").each do |line|
+                           next unless line.start_with?('VmRSS:')
+
+                           break line.split[1].to_i
+                         end
+                       }
+                     when /darwin|bsd/
+                       ->(pid) {
+                         `ps -o pid,rss -p #{pid}`.lines.last.split.last.to_i
+                       }
+                     else
+                       ->(_pid) { 0 }
+                     end
 
     self.table_name = 'good_job_processes'
     self.implicit_order_column = 'created_at'
@@ -57,6 +72,10 @@ def self.cleanup
       end
     end
 
+    def self.memory_usage(pid)
+      (PROCESS_MEMORY.call(pid) / 1024).to_i
+    end
+
     def self.find_or_create_record(id:, with_advisory_lock: false)
       attributes = {
         id: id,
@@ -84,7 +103,7 @@ def self.process_state
       {
         hostname: Socket.gethostname,
         pid: ::Process.pid,
-        memory: GetProcessMem.new.mb.to_i,
+        memory: memory_usage(::Process.pid),
         proctitle: $PROGRAM_NAME,
         preserve_job_records: GoodJob.preserve_job_records,
         retry_on_unhandled_error: GoodJob.retry_on_unhandled_error,
diff --git a/good_job.gemspec b/good_job.gemspec
index 5388a068..60d1f474 100644
--- a/good_job.gemspec
+++ b/good_job.gemspec
@@ -50,7 +50,6 @@ Gem::Specification.new do |spec|
   spec.add_dependency "fugit", ">= 1.11.0"
   spec.add_dependency "railties", ">= 6.1.0"
   spec.add_dependency "thor", ">= 1.0.0"
-  spec.add_dependency "get_process_mem", ">= 1.0.0"
 
   spec.add_development_dependency "capybara"
   spec.add_development_dependency "kramdown"