/ TEAMS · Specialist engineering · FIX protocol
Source engineers experienced in Electronic trading interfaces and connectivity. for business-critical production systems, safe integrations and measurable technical ownership.
2,000+ engineers in our active talent network · Regional recruiters
/ SYSTEM STACK
FIX session sequencing
FIX 4.x and FIXT
order lifecycle tags
resend and gap-fill
counterparty certification
/ AVAILABLE TO HIRE
Profiles show the experience we can source. Individual candidate availability is confirmed after enquiry.
Mid-level FIX Protocol Engineer
Available3+ years of experience · Poland
FIX Protocol Engineer with 3 years in production systems, focused on FIX session sequencing and FIX 4.x and FIXT.
Languages: Polish, English C1
Mid+ FIX Protocol Engineer
Inquire availability5+ years of experience · Bulgaria
FIX Protocol Engineer with 5 years in production systems, focused on FIX 4.x and FIXT and order lifecycle tags.
Languages: Bulgarian, English B2+
Senior FIX Protocol Engineer
Available9+ years of experience · Bulgaria
FIX Protocol Engineer with 9 years in production systems, focused on order lifecycle tags and resend and gap-fill.
Languages: Bulgarian, English B2+
Senior FIX Protocol Engineer
Available12+ years of experience · Serbia
FIX Protocol Engineer with 12 years in production systems, focused on resend and gap-fill and counterparty certification.
Languages: Serbian, English B2+
/ Engineering teams
Onectus uses its active engineering network and regional recruiting partners to search against concrete systems, environments and responsibilities. We evaluate practical experience rather than treating a framework mention or certification as proof of delivery. Particular availability and engagement terms are confirmed after an enquiry. For this role, practical knowledge of FIX session sequencing, FIX 4.x and FIXT, order lifecycle tags helps define the engineering search.
/ Technical specializations
The right profile depends on your actual architecture, performance constraints, integration boundaries and operational responsibilities.
FIX protocol responsibilities include fix session sequencing, related fix 4.x and fixt, clear test coverage and a reliable production handover. Examine the actual tooling and deployment environment.
FIX protocol responsibilities include fix 4.x and fixt, related order lifecycle tags, clear test coverage and a reliable production handover. Examine the actual tooling and deployment environment.
FIX protocol responsibilities include order lifecycle tags, related resend and gap-fill, clear test coverage and a reliable production handover. Examine the actual tooling and deployment environment.
FIX protocol responsibilities include resend and gap-fill, related counterparty certification, clear test coverage and a reliable production handover. Examine the actual tooling and deployment environment.
FIX protocol responsibilities include counterparty certification, related drop-copy reconciliation, clear test coverage and a reliable production handover. Examine the actual tooling and deployment environment.
FIX protocol responsibilities include drop-copy reconciliation, related fix session sequencing, clear test coverage and a reliable production handover. Examine the actual tooling and deployment environment.
/ Project scenarios
Integrate a new execution venue. Define constraints around fix session sequencing, map dependencies and test how the proposed implementation behaves under real operating conditions.
Diagnose sequence gap and reconnect failures. Define constraints around fix 4.x and fixt, map dependencies and test how the proposed implementation behaves under real operating conditions.
Validate order cancel/replace workflows. Define constraints around order lifecycle tags, map dependencies and test how the proposed implementation behaves under real operating conditions.
Reconcile trading session messages. Define constraints around resend and gap-fill, map dependencies and test how the proposed implementation behaves under real operating conditions.
/ Practical evaluation
A senior engineering interview should surface directly relevant implementation details, debugging history and operational judgment.
Describe a production issue involving FIX session sequencing and what evidence led to a fix.
Which decisions around FIX 4.x and FIXT and order lifecycle tags were you personally accountable for?
Describe a production issue involving order lifecycle tags and what evidence led to a fix.
Which decisions around resend and gap-fill and counterparty certification were you personally accountable for?
/ Sourcing process
Define platform versions, deployment constraints, traffic patterns, required integrations and ownership.
Search the active network and partner channels for platform-specific engineering experience.
Discuss real systems, code or configuration decisions, troubleshooting and change control.
Confirm role boundaries, location or remote access, availability, security and interviews.
Profiles, availability and engagement terms are confirmed for each request.
/ Questions
Yes. Tell us the relevant versions, operational environment and the responsibilities connected to FIX session sequencing. We qualify hands-on experience during each search.
These can be included when central to the project. We distinguish practical implementation work from general familiarity and ask about failure scenarios and testing.
We look at production decisions, trade-offs, incident diagnosis, code or infrastructure ownership and the ability to explain decisions without relying on a technology checklist.
Share your architecture, technical constraints, collaboration model and priorities. We can then discuss relevant sourcing channels, evaluation criteria and next steps.
/ Onectus · TEAMS
Tell us the technology, production responsibilities, experience level and working model. We'll activate the appropriate engineering sourcing channels.
