DEV Community: **dp07

Progress of project LENS......

**dp07 — Sun, 12 Jul 2026 14:07:26 +0000

that's the real progress.
I genuinely look for contributors for my repository:https://github.com/dpsyfk/lens

Building a Transparent Proxy in Rust: The Foundation Behind Lens

**dp07 — Sat, 11 Jul 2026 14:14:52 +0000

Building a Transparent Proxy in Rust: The Foundation Behind Lens

When debugging distributed applications locally, understanding how requests move between services can be surprisingly difficult.

A single request may involve an API server, authentication service, database, cache, and external APIs. Reconstructing that path often means piecing together logs from multiple places.

That's the motivation behind Lens, an open-source Rust project I'm building.

Why a Transparent Proxy?

Rather than requiring instrumentation in every application, Lens is designed around a transparent proxy architecture.

This approach allows it to observe requests and responses while remaining independent of application logic.

The long-term goals include:

Visualizing request flows
Decoding application protocols
Measuring latency
Redacting sensitive information
Supporting multiple protocols through a modular architecture

Why Rust?

Rust provides the combination of performance, memory safety, and async networking support that a project like Lens needs.

Tokio, Cargo workspaces, and Rust's type system have made it possible to design the project around small, focused crates.

Current Progress

The project currently includes:

Transparent proxy architecture
HTTP/1.1 support
PostgreSQL protocol decoding
Secret redaction
Cross-platform architecture
Interactive terminal UI (in progress)

The next milestone is implementing additional protocol support and expanding the runtime.

Looking for Feedback

If you've built networking tools, proxies, or protocol parsers in Rust, I'd genuinely appreciate feedback on the architecture.

Repository:

https://github.com/dpsyfk/lens

Designing a Transparent Proxy in Rust: The Foundation Behind Lens

**dp07 — Fri, 10 Jul 2026 18:04:07 +0000

Designing a Transparent Proxy in Rust: The Foundation Behind Lens

In my previous article, I introduced Lens, an open-source Rust project that aims to visualize application traffic during local development.

One of the first architectural decisions I had to make was how Lens should observe network traffic.

Should it inspect packets?

Use eBPF?

Require application instrumentation?

Or sit directly in the network path?

After evaluating the trade-offs, I decided to build Lens around a transparent proxy architecture.

Why a Proxy?

Consider a typical local development setup.

Client
   │
   ▼
Application
   │
   ▼
PostgreSQL

With a transparent proxy, the flow becomes:

Client
   │
   ▼
Lens Proxy
   │
   ▼
Application
   │
   ▼
Lens Proxy
   │
   ▼
PostgreSQL

This gives Lens complete visibility into requests and responses while remaining independent of application logic.

Benefits

A proxy-based design allows Lens to:

Decode application protocols
Measure request latency
Build request dependency graphs
Redact sensitive information
Support multiple protocols through a common abstraction

Challenges

The approach isn't without trade-offs.

A transparent proxy needs to:

Preserve protocol correctness
Introduce minimal latency
Handle streaming traffic
Support TLS
Remain cross-platform

Each of these influences the overall architecture.

Why Rust?

Networking software benefits from:

predictable performance
memory safety
zero-cost abstractions
excellent async support through Tokio

Rust lets me focus on protocol logic without sacrificing performance.

Looking Ahead

The next milestone is expanding protocol support while keeping the architecture modular enough to accommodate additional parsers.

I'm documenting the journey as I build Lens, so future articles will dive into topics like protocol parsing, async networking, and terminal UI design.

Repository:

https://github.com/dpsyfk/lens

I'd love contributors and their contributions.