Top Erlang Companies

Technical Evaluation Framework: Vetting Erlang & OTP Distributed Systems Engineers

Erlang and the OTP (Open Telecom Platform) framework are designed for massive concurrency, high fault tolerance, and nine-nines availability. Buyers must assess distributed systems depth.

1. Erlang & OTP Architecture

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  OTP Design Principles: Building robust supervision trees, gen_server, gen_statem, and supervisor hierarchies.
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  BEAM Concurrency & Preemption: Leveraging lightweight BEAM processes, soft real-time scheduling, and message-passing semantics.
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  Distributed Erlang Clustering: Configuring distributed node topologies, mnesia databases, and handling network partitions (netsplit).

2. Buyer Diligence & Vetting Criteria

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   Fault Tolerance & "Let It Crash" Philosophy: Engineering systems that recover gracefully from unexpected failures without cascading system outages.
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   Live System Tracing & Debugging: Production profiling and tracing using Observer, Recon, and dynamic tracing in live production nodes.
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   Hot Code Loading & Upgrades: Designing seamless releases using OTP release handlers and relup files for zero-downtime upgrades.

3. Red Flags to Watch For

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  Unbounded Process Mailboxes: Allowing worker processes to accumulate millions of unread messages, causing memory exhaustion and BEAM crashes.
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  Misconfigured Supervisors: Setting overly aggressive restart limits on supervisors, causing whole node shutdowns when a single transient worker fails.
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  Blocking BEAM Schedulers: Executing CPU-heavy computational tasks or blocking NIFs (Native Implemented Functions) on standard scheduler threads.